psychology case study h.m

Henry Gustav Molaison: The Curious Case of Patient H.M. 

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Psychology Graduate, Princeton University

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Henry Gustav Molaison, known as Patient H.M., is a landmark case study in psychology. After a surgery to alleviate severe epilepsy, which removed large portions of his hippocampus , he was left with anterograde amnesia , unable to form new explicit memories , thus offering crucial insights into the role of the hippocampus in memory formation.

• Henry Gustav Molaison (often referred to as H.M.) is a famous case of anterograde and retrograde amnesia in psychology.
• H. M. underwent brain surgery to remove his hippocampus and amygdala to control his seizures. As a result of his surgery, H.M.’s seizures decreased, but he could no longer form new memories or remember the prior 11 years of his life.
• He lost his ability to form many types of new memories (anterograde amnesia), such as new facts or faces, and the surgery also caused retrograde amnesia as he was able to recall childhood events but lost the ability to recall experiences a few years before his surgery.
• The case of H.M. and his life-long participation in studies gave researchers valuable insight into how memory functions and is organized in the brain. He is considered one of the most studied medical and psychological history cases.

Who is H.M.?

Henry Gustav Molaison, or “H.M” as he is commonly referred to by psychology and neuroscience textbooks, lost his memory on an operating table in 1953.

For years before his neurosurgery, H.M. suffered from epileptic seizures believed to be caused by a bicycle accident that occurred in his childhood. The seizures started out as minor at age ten, but they developed in severity when H.M. was a teenager.

Continuing to worsen in severity throughout his young adulthood, H.M. was eventually too disabled to work. Throughout this period, treatments continued to turn out unsuccessful, and epilepsy proved a major handicap and strain on H.M.’s quality of life.

And so, at age 27, H.M. agreed to undergo a radical surgery that would involve removing a part of his brain called the hippocampus — the region believed to be the source of his epileptic seizures (Squire, 2009).

For epilepsy patients, brain resection surgery refers to removing small portions of brain tissue responsible for causing seizures. Although resection is still a surgical procedure used today to treat epilepsy, the use of lasers and detailed brain scans help ensure valuable brain regions are not impacted.

In 1953, H.M.’s neurosurgeon did not have these tools, nor was he or the rest of the scientific or medical community fully aware of the true function of the hippocampus and its specific role in memory. In one regard, the surgery was successful, as H.M. did, in fact, experience fewer seizures.

However, family and doctors soon noticed he also suffered from severe amnesia, which persisted well past when he should have recovered. In addition to struggling to remember the years leading up to his surgery, H.M. also had gaps in his memory of the 11 years prior.

Furthermore, he lacked the ability to form new memories — causing him to perpetually live an existence of moment-to-moment forgetfulness for decades to come.

In one famous quote, he famously and somberly described his state as “like waking from a dream…. every day is alone in itself” (Squire et al., 2009).

H.M. soon became a major case study of interest for psychologists and neuroscientists who studied his memory deficits and cognitive abilities to better understand the hippocampus and its function.

When H.M. died on December 2, 2008, at the age of 82, he left behind a lifelong legacy of scientific contribution.

Surgical Procedure

Neurosurgeon William Beecher Scoville performed H.M.’s surgery in Hartford, Connecticut, in August 1953 when H.M. was 27 years old.

During the procedure, Scoville removed parts of H.M.’s temporal lobe which refers to the portion of the brain that sits behind both ears and is associated with auditory and memory processing.

More specifically, the surgery involved what was called a “partial medial temporal lobe resection” (Scoville & Milner, 1957). In this resection, Scoville removed 8 cm of brain tissue from the hippocampus — a seahorse-shaped structure located deep in the temporal lobe .

Bilateral resection of the anterior temporal lobe in patient HM.

Further research conducted after this removal showed Scoville also probably destroyed the brain structures known as the “uncus” (theorized to play a role in the sense of smell and forming new memories) and the “amygdala” (theorized to play a crucial role in controlling our emotional responses such as fear and sadness).

As previously mentioned, the removal surgery partially reduced H.M.’s seizures; however, he also lost the ability to form new memories.

At the time, Scoville’s experimental procedure had previously only been performed on patients with psychosis, so H.M. was the first epileptic patient and showed no sign of mental illness. In the original case study of H.M., which is discussed in further detail below, nine of Scoville’s patients from this experimental surgery were described.

However, because these patients had disorders such as schizophrenia, their symptoms were not removed after surgery.

In this regard, H.M. was the only patient with “clean” amnesia along with no other apparent mental problems.

H.M’s Amnesia

H.M.’s apparent amnesia after waking from surgery presented in multiple forms. For starters, H.M. suffered from retrograde amnesia for the 11-year period prior to his surgery.

Retrograde describes amnesia, where you can’t recall memories that were formed before the event that caused the amnesia. Important to note, current research theorizes that H.M.’s retrograde amnesia was not actually caused by the loss of his hippocampus, but rather from a combination of antiepileptic drugs and frequent seizures prior to his surgery (Shrader 2012).

In contrast, H.M.’s inability to form new memories after his operation, known as anterograde amnesia, was the result of the loss of the hippocampus.

This meant that H.M. could not learn new words, facts, or faces after his surgery, and he would even forget who he was talking to the moment he walked away.

However, H.M. could perform tasks, and he could even perform those tasks easier after practice. This important finding represented a major scientific discovery when it comes to memory and the hippocampus. The memory that H.M. was missing in his life included the recall of facts, life events, and other experiences.

This type of long-term memory is referred to as “explicit” or “ declarative ” memories and they require conscious thinking.

In contrast, H.M.’s ability to improve in tasks after practice (even if he didn’t recall that practice) showed his “implicit” or “ procedural ” memory remained intact (Scoville & Milner, 1957). This type of long-term memory is unconscious, and examples include riding a bike, brushing your teeth, or typing on a keyboard.

Most importantly, after removing his hippocampus, H.M. lost his explicit memory but not his implicit memory — establishing that implicit memory must be controlled by some other area of the brain and not the hippocampus.

After the severity of the side effects of H.M.’s operation became clear, H.M. was referred to neurosurgeon Dr. Wilder Penfield and neuropsychologist Dr. Brenda Milner of Montreal Neurological Institute (MNI) for further testing.

As discussed, H.M. was not the only patient who underwent this experimental surgery, but he was the only non-psychotic patient with such a degree of memory impairment. As a result, he became a major study and interest for Milner and the rest of the scientific community.

Since Penfield and Milner had already been conducting memory experiments on other patients at the time, they quickly realized H.M.’s “dense amnesia, intact intelligence, and precise neurosurgical lesions made him a perfect experimental subject” (Shrader 2012).

Milner continued to conduct cognitive testing on H.M. for the next fifty years, primarily at the Massachusetts Institute of Technology (MIT). Her longitudinal case study of H.M.’s amnesia quickly became a sensation and is still one of the most widely-cited psychology studies.

In publishing her work, she protected Henry’s identity by first referring to him as the patient H.M. (Shrader 2012).

In the famous “star tracing task,” Milner tested if H.M.’s procedural memory was affected by the removal of the hippocampus during surgery.

In this task, H.M. had to trace an outline of a star, but he could only trace the star based on the mirrored reflection. H.M. then repeated this task once a day over a period of multiple days.

Over the course of these multiple days, Milner observed that H.M. performed the test faster and with fewer errors after continued practice. Although each time he performed the task, he had no memory of having participated in the task before, his performance improved immensely (Shrader 2012).

As this task showed, H.M. had lost his declarative/explicit memory, but his unconscious procedural/implicit memory remained intact.

Given the damage to his hippocampus in surgery, researchers concluded from tasks such as these that the hippocampus must play a role in declarative but not procedural memory.

Therefore, procedural memory must be localized somewhere else in the brain and not in the hippocampus.

H.M’s Legacy

Milner’s and hundreds of other researchers’ work with H.M. established fundamental principles about how memory functions and is organized in the brain.

Without the contribution of H.M. in volunteering the study of his mind to science, our knowledge today regarding the separation of memory function in the brain would certainly not be as strong.

Until H.M.’s watershed surgery, it was not known that the hippocampus was essential for making memories and that if we lost this valuable part of our brain, we would be forced to live only in the moment-to-moment constraints of our short-term memory .

Once this was realized, the findings regarding H.M. were widely publicized so that this operation to remove the hippocampus would never be done again (Shrader 2012).

H.M.’s case study represents a historical time period for neuroscience in which most brain research and findings were the result of brain dissections, lesioning certain sections, and seeing how different experimental procedures impacted different patients.

Therefore, it is paramount we recognize the contribution of patients like H.M., who underwent these dangerous operations in the mid-twentieth century and then went on to allow researchers to study them for the rest of their lives.

Even after his death, H.M. donated his brain to science. Researchers then took his unique brain, froze it, and then in a 53-hour procedure, sliced it into 2,401 slices which were then individually photographed and digitized as a three-dimensional map.

Through this map, H.M.’s brain could be preserved for posterity (Wb et al., 2014). As neuroscience researcher Suzanne Corkin once said it best, “H.M. was a pleasant, engaging, docile man with a keen sense of humor, who knew he had a poor memory but accepted his fate.

There was a man behind the data. Henry often told me that he hoped that research into his condition would help others live better lives. He would have been proud to know how much his tragedy has benefitted science and medicine” (Corkin, 2014).

Corkin, S. (2014). Permanent present tense: The man with no memory and what he taught the world. Penguin Books.

Hardt, O., Einarsson, E. Ö., & Nader, K. (2010). A bridge over troubled water: Reconsolidation as a link between cognitive and neuroscientific memory research traditions. Annual Review of Psychology, 61, 141–167.

Scoville, W. B., & Milner, B. (1957). Loss of recent memory after bilateral hippocampal lesions . Journal of neurology, neurosurgery, and psychiatry, 20 (1), 11.

Shrader, J. (2012, January). HM, the man with no memory | Psychology Today. Retrieved from, https://www.psychologytoday.com/us/blog/trouble-in-mind/201201/hm-the-man-no-memory

Squire, L. R. (2009). The legacy of patient H. M. for neuroscience . Neuron, 61 , 6–9.

HM, the Man with No Memory

Henry molaison (hm) taught us about memory by losing his..

Posted January 16, 2012 | Reviewed by Jessica Schrader

Henry Molaison, known by thousands of psychology students as "HM," lost his memory on an operating table in a hospital in Hartford in August 1953. He was 27 years old and had suffered from epileptic seizures for many years.

William Beecher Scoville, a Hartford neurosurgeon , stood above an awake Henry and skilfully suctioned out the seahorse-shaped brain structure called the hippocampus that lay within each temporal lobe. Henry would have been drowsy and probably didn't notice his memory vanishing as the operation proceeded.

The operation was successful in that it significantly reduced Henry's seizures, but it left him with a dense memory loss. When Scoville realized his patient had become amnesic, he referred him to the eminent neurosurgeon Dr. Wilder Penfield and neuropsychologist Dr. Brenda Milner of Montreal Neurological Institute (MNI), who assessed him in detail. Up until then, it had not been known that the hippocampus was essential for making memories, and that if we lose both of them we will suffer a global amnesia. Once this was realized, the findings were widely publicized so that this operation to remove both hippocampi would never be done again.

Penfield and Milner had already been conducting memory experiments on other patients and they quickly realized that Henry's dense amnesia, his intact intelligence , and the precise neurosurgical lesions made him the perfect experimental subject. For 55 years, Henry participated in numerous experiments, primarily at Massachusetts Institute of Technology (MIT), where Professor Suzanne Corkin and her team of neuropsychologists assessed him.

Access to Henry was carefully restricted to less than 100 researchers (I was honored to be one of them), but the MNI and MIT studies on HM taught us much of what we know about memory. Of course, many other patients with memory impairments have since been studied, including a small number with amnesias almost as dense as Henry's, but it is to him we owe the greatest debt. His name (or initials!) has been mentioned in almost 12,000 journal articles, making him the most studied case in medical or psychological history. Henry died on December 2, 2008, at the age of 82. Until then, he was known to the world only as "HM," but on his death his name was revealed. A man with no memory is vulnerable, and his initials had been used while he lived in order to protect his identity .

Henry's memory loss was far from simple. Not only could he make no new conscious memories after his operation, he also suffered a retrograde memory loss (a loss of memories prior to brain damage) for an 11-year period before his surgery. It is not clear why this is so, although it is thought this is not because of his loss of the hippocampi on both sides of his brain. More likely it is a combination of his being on large doses of antiepileptic drugs and his frequent seizures prior to his surgery. His global amnesia for new material was the result of the loss of both hippocampi, and meant that he could not learn new words, songs or faces after his surgery, forgot who he was talking to as soon as he turned away, didn't know how old he was or if his parents were alive or dead, and never again clearly remembered an event, such as his birthday party, or who the current president of the United States was.

In contrast, he did retain the ability to learn some new motor skills, such as becoming faster at drawing a path through a picture of a maze, or learning to use a walking frame when he sprained his ankle, but this learning was at a subconscious level. He had no conscious memory that he had ever seen or done the maze test before, or used the walking frame previously.

We measure time by our memories, and thus for Henry, it was as if time stopped when he was 16 years old, 11 years before his surgery. Because his intelligence in other non-memory areas remained normal, he was an excellent experimental participant. He was also a very happy and friendly person and always a delight to be with and to assess. He never seemed to get tired of doing what most people would think of as tedious memory tests, because they were always new to him! When he was at MIT, between test sessions he would often sit doing crossword puzzles, and he could do the same ones again and again if the words were erased, as to him it was new each time.

Henry gave science the ultimate gift: his memory. Thousands of people who have suffered brain damage, whether through accident, disease or a genetic quirk, have given similar gifts to science by agreeing to participate in psychological, neuropsychological, psychiatric and medical studies and experiments, and in some cases by gifting their brains to science after their deaths. Our knowledge of brain disease and how the normal mind works would be greatly diminished if it were not for the generosity of these people and their families (who are frequently also involved in interviews, as well as transporting the "patient" back and forth to the psychology laboratory). After Henry's death, his brain was dissected into 2,000 slices and digitized as a three-dimensional brain map that could be searched by zooming in from the whole brain to individual neurons. Thus, his tragically unique brain has been preserved for posterity.

Jenni Ogden, Ph.D. , clinical neuropsychologist and author of Trouble in Mind, taught at the University of Auckland.

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Key Study: HM’s case study (Milner and Scoville, 1957)

Travis Dixon January 29, 2019 Biological Psychology , Cognitive Psychology , Key Studies

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HM’s case study is one of the most famous and important case studies in psychology, especially in cognitive psychology. It was the source of groundbreaking new knowledge on the role of the hippocampus in memory. 

Background Info

“Localization of function in the brain” means that different parts of the brain have different functions. Researchers have discovered this from over 100 years of research into the ways the brain works. One such study was Milner’s case study on Henry Molaison.

The memory problems that HM experienced after the removal of his hippocampus provided new knowledge on the role of the hippocampus in memory formation (image: wikicommons)

At the time of the first study by Milner, HM was 29 years old. He was a mechanic who had suffered from minor epileptic seizures from when he was ten years old and began suffering severe seizures as a teenager. These may have been a result of a bike accident when he was nine. His seizures were getting worse in severity, which resulted in HM being unable to work. Treatment for his epilepsy had been unsuccessful, so at the age of 27 HM (and his family) agreed to undergo a radical surgery that would remove a part of his brain called the hippocampus . Previous research suggested that this could help reduce his seizures, but the impact it had on his memory was unexpected. The Doctor performing the radical surgery believed it was justified because of the seriousness of his seizures and the failures of other methods to treat them.

Methods and Results

In one regard, the surgery was successful as it resulted in HM experiencing less seizures. However, immediately after the surgery, the hospital staff and HM’s family noticed that he was suffering from anterograde amnesia (an inability to form new memories after the time of damage to the brain):

Here are some examples of his memory loss described in the case study:

• He could remember something if he concentrated on it, but if he broke his concentration it was lost.
• After the surgery the family moved houses. They stayed on the same street, but a few blocks away. The family noticed that HM as incapable of remembering the new address, but could remember the old one perfectly well. He could also not find his way home alone.
• He could not find objects around the house, even if they never changed locations and he had used them recently. His mother had to always show him where the lawnmower was in the garage.
• He would do the same jigsaw puzzles or read the same magazines every day, without ever apparently getting bored and realising he had read them before. (HM loved to do crossword puzzles and thought they helped him to remember words).
• He once ate lunch in front of Milner but 30 minutes later was unable to say what he had eaten, or remember even eating any lunch at all.
• When interviewed almost two years after the surgery in 1955, HM gave the date as 1953 and said his age was 27. He talked constantly about events from his childhood and could not remember details of his surgery.

Later testing also showed that he had suffered some partial retrograde amnesia (an inability to recall memories from before the time of damage to the brain). For instance, he could not remember that one of his favourite uncles passed away three years prior to his surgery or any of his time spent in hospital for his surgery. He could, however, remember some unimportant events that occurred just before his admission to the hospital.

Brenda Milner studied HM for almost 50 years – but he never remembered her.

Results continued…

His memories from events prior to 1950 (three years before his surgery), however, were fine. There was also no observable difference to his personality or to his intelligence. In fact, he scored 112 points on his IQ after the surgery, compared with 104 previously. The IQ test suggested that his ability in arithmetic had apparently improved. It seemed that the only behaviour that was affected by the removal of the hippocampus was his memory. HM was described as a kind and gentle person and this did not change after his surgery.

The Star Tracing Task

In a follow up study, Milner designed a task that would test whether or not HMs procedural memory had been affected by the surgery. He was to trace an outline of a star, but he could only see the mirrored reflection. He did this once a day over a period of a few days and Milner observed that he became faster and faster. Each time he performed the task he had no memory of ever having done it before, but his performance kept improving. This is further evidence for localization of function – the hippocampus must play a role in declarative (explicit) memory but not procedural (implicit) memory.

Cognitive psychologists have categorized memories into different types. HM’s study suggests that the hippocampus is essential for explicit (conscious) and declarative memory, but not implicit (unconscious) procedural memory.

Was his memory 100% gone? Another follow-up study

Interestingly, HM showed signs of being able to remember famous people who had only become famous after his surgery, like Lee Harvey Oswald (who assassinated JFK in 1963). (Image: wikicommons)

Another fascinating follow-up study was conducted by two researchers who wanted to see if HM had learned anything about celebrities that became famous after his surgery. At first they tested his knowledge of celebrities from before his surgery, and he knew these just as well as controls. They then showed him two names at a time, one a famous name (e.g. Liza Minelli, Lee Harvey Oswald) and the other was a name randomly taken from the phonebook. He was asked to choose the famous name and he was correct on a significant number of trials (i.e. the statistics tests suggest he wasn’t just guessing). Even more incredible was that he remembered some details about these people when asked why they were famous. For example, he could remember that Lee Harvey Oswald assassinated the president. One explanation given for the memory of these facts is that there was an emotional component. E.g. He liked these people, or the assassination was so violent, that he could remember a few details. 

HM became a hugely important case study for neuro and cognitive Psychologists. He was interviewed and tested by over 100 psychologists during the 53 years after his operation. Directly after his surgery, he lived at home with his parents as he was unable to live independently. He moved to a nursing home in 1980 and stayed there until his death in 2008. HM donated his brain to science and it was sliced into 2,401 thin slices that will be scanned and published electronically.

Critical Thinking Considerations

• How does this case study demonstrate localization of function in the brain? (e.g.c reating new long-term memories; procedural memories; storing and retrieving long term memories; intelligence; personality) ( Application )
• What are the ethical considerations involved in this study? ( Analysis )
• What are the strengths and limitations of this case study? ( Evaluation )
• Why would ongoing studies of HM be important? (Think about memory, neuroplasticity and neurogenesis) ( Analysis/Synthesis/Evaluation )
• How can findings from this case study be used to support and/or challenge the Multi-store Model of Memory? ( Application / Synthesis/Evaluation )

Exam Tips This study can be used for the following topics: Localization – the role of the hippocampus in memory Techniques to study the brain – MRI has been used to find out the exact location and size of damage to HM’s brain Bio and cognitive approach research method s – case study Bio and cognitive approach ethical considerations – anonymity Emotion and cognition – the follow-up study on HM and memories of famous people could be used in an essay to support the idea that emotion affects memory Models of memory – the multi-store model : HM’s study provides evidence for the fact that our memories all aren’t formed and stored in one place but travel from store to store (because his transfer from STS to LTS was damaged – if it was all in one store this specific problem would not occur)

Milner, Brenda. Scoville, William Beecher. “Loss of Recent Memory after Bilateral Hippocampal Lesions”. The Journal of Neurology, Neurosurgery and Psychiatry. 1957; 20: 11 21. (Accessed from web.mit.edu )

The man who couldn’t remember”. nova science now. an interview with brenda corkin . 06.01.2009.       .

  Here’s a good video recreation documentary of HM’s case study…

Travis Dixon is an IB Psychology teacher, author, workshop leader, examiner and IA moderator.

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The Legacy of Patient H.M. for Neuroscience

Larry r. squire.

1 Veterans Affairs Healthcare System, San Diego, CA 92161, USA

2 Departments of Psychiatry, Neurosciences, and Psychology, University of California, San Diego, La Jolla, CA 92093, USA

H.M. is probably the best known single patient in the history of neuroscience. His severe memory impairment, which resulted from experimental neurosurgery to control seizures, was the subject of study for five decades until his death in December 2008. Work with H.M. established fundamental principles about how memory functions are organized in the brain.

In 1952, Brenda Milner was completing her doctoral research at McGill University under the direction of Donald Hebb. At about this time, she encountered two patients (P.B. and F.C.) who had become severely amnesic following unilateral removal of the medial structures of the left temporal lobe for the treatment of epileptic seizures ( Penfield and Milner, 1958 ). This unfortunate outcome was entirely unexpected, and it was proposed that in each case there had been a preexistent, but unsuspected, atrophic lesion in the medial temporal lobe of the opposite hemisphere. In that way, the unilateral surgery would have resulted in a bilateral lesion, an idea that was confirmed at autopsy some years later for patient P.B. After the two cases were presented at the 1955 meeting of the American Neurological Association, Wilder Penfield (the neurosurgeon in both cases) received a call from William Scoville, a neurosurgeon in Hartford, Connecticut. Scoville told Penfield that he had seen a similar memory impairment in one of his own patients (H.M.) in whom he had carried out a bilateral medial temporal lobe resection in an attempt to control epileptic seizures. As a result of this conversation, Brenda Milner was invited to travel to Hartford to study H.M.

H.M. had been knocked down by a bicycle at the age of 7, began to have minor seizures at age 10, and had major seizures after age 16. (The age of the bicycle accident is given as 9 in some reports; for clarification see Corkin, 1984 .) He worked for a time on an assembly line but, finally, in 1953 at the age of 27 he had become so incapacitated by his seizures, despite high doses of anticonvulsant medication, that he could not work or lead a normal life. Scoville offered H.M. an experimental procedure that he had carried out previously in psychotic patients, and the surgery was then performed with the approval of the patient and his family.

When Milner first visited H.M., she saw that the epilepsy was now controlled but that his memory impairment was even more severe than in Penfield’s two patients, P.B. and F.C. What she observed was someone who forgot daily events nearly as fast as they occurred, apparently in the absence of any general intellectual loss or perceptual disorder. He underestimated his own age, apologized for forgetting the names of persons to whom he had just been introduced, and described his state as “like waking from a dream ... every day is alone in itself...” ( Milner et al., 1968 , p. 217).

The first observations of H.M., and the results of formal testing, were reported a few years later ( Scoville and Milner, 1957 ). This publication became one of the most cited papers in neuroscience (nearly 2500 citations) and is still cited with high frequency. H.M. continued to be studied for five decades, principally by Brenda Milner, her former student Suzanne Corkin, and their colleagues ( Corkin, 1984 , 2002 ; Milner et al., 1968 ). He died on December 2, 2008, at the age of 82. It can be said that the early descriptions of H.M. inaugurated the modern era of memory research. Before H.M., due particularly to the influence of Karl Lashley, memory functions were thought to be widely distributed in the cortex and to be integrated with intellectual and perceptual functions. The findings from H.M. established the fundamental principle that memory is a distinct cerebral function, separable from other perceptual and cognitive abilities, and identified the medial aspect of the temporal lobe as important for memory. The implication was that the brain has to some extent separated its perceptual and intellectual functions from its capacity to lay down in memory the records that ordinarily result from engaging in perceptual and intellectual work.

The Medial Temporal Lobe Memory System

The early paper is sometimes cited incorrectly as evidence that the hippocampus is important for memory, but this particular point could not of course be established from a lesion that, by the surgeon’s description, included the hippocampus, amygdala, and the adjacent parahippocampal gyrus. As Milner subsequently wrote, “Despite the use of the word ‘hippocampal’ in the titles of my papers with Scoville and Penfield, I have never claimed that the memory loss was solely attributable to the hippocampal lesions” ( Milner, 1998 ). Indeed, the original paper ends, quite appropriately, with the statement:

It is concluded that the anterior hippocampus and hippocampal gyrus, either separately or together, are critically concerned in the retention of current experience. It is not known whether the amygdala plays any part in this mechanism, since the hippocampal complex has not been removed alone, but always together with uncus and amygdala. ( Scoville and Milner, 1957 , p. 21).

The findings from H.M. were initially met with some resistance, especially because of the difficulty for many years of demonstrating anything resembling his impairment in the experimental animal. Efforts to establish an animal model in fact began almost immediately when Scoville himself came to Montreal and did the same surgery in monkeys that he had done with H.M. But these monkeys and others with medial temporal lesions seemed able to learn tasks that H.M. could not learn. Only much later did it become understood that apparently similar tasks can be learned in different ways by humans and monkeys. For example, the visual discrimination task, which is learned gradually by the monkey over hundreds of trials, proved to involve what one would now call habit learning. In the monkey, this kind of learning depends on the basal ganglia, not the medial temporal lobe. Eventually, tasks were developed for the monkey that were exquisitely sensitive to medial temporal lobe lesions (for example, the one-trial, delayed nonmatching to sample task), and an animal model of human memory impairment thereby became available ( Mishkin, 1978 ).

Cumulative work with the animal model over the next decade, together with neuroanatomical studies, succeeded in identifying the anatomical components of what is now termed the medial temporal lobe memory system ( Squire and Zola-Morgan, 1991 ): the hippocampus and the adjacent perirhinal, entorhinal, and parahippocampal cortices that make up much of the parahippocampal gyrus. This information showed which structures within H.M.’s large lesion were important for understanding his impairment and, more broadly, what structures are important for memory. A few years later, an improved description of H.M.’s lesion was obtained with magnetic resonance imaging (MRI) ( Corkin et al., 1997 ). MRI had been delayed because of concerns that clips placed on the dura during surgery made H.M. ineligible for imaging. However, thorough inquiry revealed that the dural clips constituted no risk.

At this juncture, several points became clear. First, H.M.’s lesion was less extensive than described originally by the surgeon in that it extended a little more than 5 cm caudally from the temporal pole (not 8 cm). As a result the posterior parahippocampal gyrus was largely spared (specifically, the parahippocampal cortex or what in the monkey is termed area TH TF). Second, the reason that H.M.’s memory impairment was so severe was that the bilateral damage included the parahippocampal gyrus (anteriorly) and was not restricted to the hippocampus. Damage limited to the hippocampus causes significant memory impairment but considerably less impairment than in H.M. Third, memory impairment more severe than H.M.’s could now be understood, as when the damage includes the structures damaged in H.M. but also extends far enough posteriorly to involve the parahippocampal cortex (patients E.P. and G.P.; Kirwan et al., 2008 ).

In the early years, the anatomy of the medial temporal lobe was poorly understood, and terms like hippocampal zone and hippocampal complex were often used to identify the area of damage. With the elucidation of the boundaries and connectivity of the structures adjacent to the hippocampus and the discovery that these structures are important for memory, vague terms like hippocampal complex became unnecessary (though one can still find them in contemporary writing). It is now possible to achieve careful descriptions based on anatomical measurement and modern terminology.

H.M. not only motivated the development of an animal model of human memory impairment and the subsequent delineation of the medial temporal lobe memory system. As described next, the study of H.M. also led to fundamental insights into the function of the medial temporal lobe and the larger matter of how memory is organized in the brain.

Immediate Memory and Long-Term Memory

H.M.’s intact intellectual and perceptual functions, and similar findings in other patients with large medial temporal lesions, have been well documented. A key additional finding was that H.M. had a remarkable capacity for sustained attention, including the ability to retain information for a period of time after it was presented. Thus, he could carry on a conversation, and he exhibited an intact digit span (i.e., the ability to repeat back a string of six or seven digits). Indeed, information remained available so long as it could be actively maintained by rehearsal. For example, H.M. could retain a three-digit number for as long as 15 min by continuous rehearsal, organizing the digits according to an elaborate mnemonic scheme. Yet when his attention was diverted to a new topic, he forgot the whole event. In contrast, when the material was not easy to rehearse (in the case of nonverbal stimuli like faces or designs), information slipped away in less than a minute. These findings supported a fundamental distinction between immediate memory and long-term memory (what William James termed primary memory and secondary memory). Primary memory [immediate memory]

...comes to us as belonging to the rearward portion of the present space of time, and not to the genuine past ( James, 1890 , p. 647).

Secondary memory [long-term memory] is quite different.

An object which has been recollected. is one which has been absent from consciousness altogether, and now revives anew. It is brought back, recalled, fished up, so to speak, from a reservoir in which, with countless other objects, it lay buried and lost from view. ( James, 1890 , p. 648).

Notably, time is not the key factor that determines how long patients like H.M. can retain information in memory. The relevant factors are the capacity of immediate memory and attention, i.e., the amount of material that can be held in mind and how successfully it can be rehearsed. The work with H.M. demonstrated that the psychological distinction between immediate memory and long-term memory is a prominent feature of how the brain has organized its memory functions.

Multiple Memory Systems

Perhaps the most unexpected discovery about H.M., given his profound and global memory impairment, came when Brenda Milner tested his ability to acquire a visuomotor skill ( Milner, 1962 ). H.M. was shown a five-pointed star, with a double contour, and asked to trace its outline with a pencil, but in a condition when he could only see his hand and the star as reflected in a mirror. H.M. acquired this mirror-drawing skill during ten trials and exhibited excellent retention across 3 days. Yet at the end of testing, he had no recollection of having done the task before. This demonstration provided the first hint that there was more than one kind of memory in the brain and suggested that some kinds of memory (motor skills) must lie outside the province of the medial temporal lobe.

For a time, it was rather thought that motor skills were a special case and that all the rest of memory is impaired in patients like H.M. Later it became appreciated that motor skills are but a subset of a larger domain of skill-like abilities, all of which are preserved in amnesia. The demonstration of a fully preserved ability to learn the perceptual skill of mirror reading suggested a distinction between two broad classes of knowledge: declarative and procedural ( Cohen and Squire, 1980 ). Declarative memory is what is meant when the term “memory” is used in everyday language, i.e., conscious knowledge of facts and events. Procedural memory refers to skill-based knowledge that develops gradually but with little ability to report what is being learned.

In the years that followed, other preserved learning abilities began to be reported for amnesic patients, and the perspective shifted to a framework that accommodated multiple (i.e., more than two) memory systems. As Endel Tulving wrote:

But even if we accept the broad division of memory into procedural and propositional forms ... there are phenomena that do not seem to fit readily into such a taxonomy ( Tulving et al., 1982 , p.336).

Subsequently, the terms declarative and nondeclarative were introduced with the idea that declarative memory refers to the kind of memory that is impaired in H.M. and is dependent on the medial temporal lobe. Nondeclarative memory is an umbrella term referring to additional memory systems. These include systems that support skill learning, habit learning, simple conditioning, emotional learning, as well as priming and perceptual learning. The structures with special importance for these kinds of memory include the basal ganglia, the cerebellum, the amygdala, and the neocortex. The starting point for these developments was the early discovery that motor skill learning was preserved in H.M. This finding revealed that memory is not a single faculty of the mind and led ultimately to the identification of the multiple memory systems of the mammalian brain.

Remote Memory

H.M.’s memory impairment has generally been taken as reflecting a failure to convert transient, immediate memory into stable long-term memory. A key insight about the organization of memory, and medial temporal lobe function, came with a consideration of his capacity to remember information that he had acquired before his surgery. The first exploration of this issue with formal tests asked H.M. to recognize faces of persons who had become famous in different decades, 1920-1970 ( Marslen-Wilson and Teuber, 1975 ). As expected, H.M. was severely impaired at recognizing faces from his postmorbid period (the 1950s and 1960s), but he performed as well as or better than age-matched controls at recognizing faces of persons who were in the news before his surgery. This important finding implied that the medial temporal lobe is not the ultimate storage site for previously acquired knowledge. The early descriptions of H.M. conform to this view. Thus, H.M. was described as having a partial loss of memory (retrograde amnesia) for the 3 years leading up to his surgery, with early memories “seemingly normal” ( Scoville and Milner, 1957 , p. 17). Similarly, about 10 years later it was remarked that there did not appear

to have been any change in H.M.’s capacity to recall remote events antedating his operation, such as incidents from his early school years, a high-school attachment, or jobs he had held in his late teens and early twenties ( Milner et al., 1968 , p. 216).

Subsequently, a particular interest developed in the status of autobiographical memories for unique events, which are specific to time and place, and methods were developed to assess the specificity and the detail with which such recollections could be reproduced. In the earliest efforts along these lines, as summarized by Suzanne Corkin ( Corkin, 1984 ), H.M. produced well-formed autobiographical memories, from age 16 years or younger. It was concluded that H.M’s remote memory impairment now extended back to 11 years before his surgery. The situation seemed to change further as H.M. aged. In an update prepared nearly 20 years later ( Corkin, 2002 ), H.M. (now 76 years old) was described as having memories of childhood, but his memories appeared more like remembered facts than like memories of specific episodes. It was also said that he could not narrate a single event that occurred at a specific time and place. Essentially the same conclusion was reached a few years later when new methods, intended to be particularly sensitive, were used to assess H.M.’s remote memory for autobiographical events ( Steinvorth et al., 2005 ). These later findings led to the proposal that, whatever might be the case for fact memory, autobiographical memories, i.e., memories that are specific to time and place, depend on the medial temporal lobe so long as the memories persist.

There are reasons to be cautious about this idea. In 2002-2003, new MRI scans of H.M. were obtained ( Salat et al., 2006 ). These scans documented a number of changes since his first MRI scans from 1992-1993 ( Corkin et al., 1997 ), including cortical thinning, subcortical atrophy, large amounts of abnormal white matter, and subcortical infarcts. These findings were thought to have appeared during the past decade, and they complicate the interpretation of neuropsychological data collected during the same time period. Another consideration is that remote memories could have been intact in the early years after surgery but then have faded with time because they could not be strengthened through rehearsal and relearning. In any case, the optimal time to assess the status of past memory is soon after the onset of memory impairment.

Other work has tended to support the earlier estimates that H.M.’s remote memories were intact. First, Penfield’s two patients described above, P.B. and F.C., were reported after their surgeries to have memory loss extending back a few months and 4 years, respectively, and intact memory from before that time ( Penfield and Milner, 1958 ). Second, methods like those used recently to assess H.M. have also been used to evaluate autobiographical memory in other patients, including patients like E.P. and G.P. who have very severe memory impairment ( Kirwan et al., 2008 ). In these cases, autobiographical recollection was impaired when memories were drawn from the recent past but fully intact when memories were drawn from the remote past.

Memory loss can sometimes extend back for decades in the case of large medial temporal lobe lesions (though additional damage to anterolateral temporal cortex may be important in this circumstance). In any case, memories from early life appear to be intact unless the damage extends well into the lateral temporal lobe or the frontal lobe. These findings are typically interpreted to mean that the structures damaged in H.M. are important for the formation of long-term memory and its maintenance for a period of time after learning. During this period gradual changes are thought to occur in neocortex (memory consolidation) that increase the complexity, distribution, and connectivity among multiple cortical regions. Eventually, memory can be supported by the neocortex and becomes independent of the medial temporal lobe. The surprising observation that H.M. had access to old memories, in the face of an inability to establish new ones, motivated an enormous body of work, both in humans and experimental animals, on the topic of remote memory and continues to stimulate discussion about the nature and significance of retrograde amnesia.

Perspective

H.M. was likely the most studied individual in the history of neuroscience. Interest in the case can be attributed to a number of factors, including the unusual purity and severity of the memory impairment, its stability, its well-described anatomical basis, and H.M.’s willingness to be studied. He was a quiet and courteous man with a sense of humor and insight into his condition. Speaking of his neurosurgeon, he once said, “What he learned about me helped others, and I’m glad about that.” ( Corkin, 2002 , p. 159).

An additional aspect of H.M.’s circumstance, which assured his eventual place in the history of neuroscience, was the fact that Brenda Milner was the young scientist who first studied him. She is a superb experimentalist with a strong conceptual orientation that allowed her to draw from her data deep insights about the organization of memory. Because he was the first well-studied patient with amnesia, H.M. became the yardstick against which other patients with memory impairment would be compared. It is now clear that his memory impairment was not absolute and that he was able to acquire significant new knowledge ( Corkin, 2002 ). Thus, memory impairment can be either more severe or less severe than in H.M. But the study of H.M. established key principles about how memory is organized that continue to guide the discipline.

ACKNOWLEDGMENTS

Supported by the Medical Research Service of the Department of Veterans Affairs, The National Institute of Mental Health (MH24600), and the Metro-politan Life Foundation. I thank Nicola Broadbent, Robert Clark, Christine Smith, Ryan Squire, and Wendy Suzuki for their helpful comments.

• Cohen N, Squire LR. Science. 1980; 210 :207–209. [ PubMed ] [ Google Scholar ]
• Corkin S. Semin. Neurol. 1984; 4 :249–259. [ Google Scholar ]
• Corkin S. Nat. Rev. Neurosci. 2002; 3 :153–160. [ PubMed ] [ Google Scholar ]
• Corkin S, Amaral DG, Gonzalez RG, Johnson KA, Hyman BT. J. Neurosci. 1997; 17 :3964–3979. [ PMC free article ] [ PubMed ] [ Google Scholar ]
• James W. Principles of Psychology. Dover Edition One. Holt; New York: 1890. [ Google Scholar ]
• Kirwan CB, Bayley PJ, Galván VV, Squire LR. Proc. Natl. Acad. Sci. USA. 2008; 105 :2676–2680. [ PMC free article ] [ PubMed ] [ Google Scholar ]
• Marslen-Wilson WD, Teuber HL. Neuropsychologia. 1975; 13 :353–364. [ PubMed ] [ Google Scholar ]
• Milner B. In: Physiologie de l’hippocampe. Passouant P, editor. Centre National de la Recherche Scientifique; Paris: 1962. pp. 257–272. [ Google Scholar ]
• Milner B. In: The History of Neuroscience in Autobiography. Squire LR, editor. Vol. 2. Academic Press; San Diego: 1998. pp. 276–305. [ Google Scholar ]
• Milner B, Corkin S, Teuber HL. Neuropsychologia. 1968; 6 :215–234. [ Google Scholar ]
• Mishkin M. Nature. 1978; 273 :297–298. [ PubMed ] [ Google Scholar ]
• Penfield W, Milner B. AMA Arch. Neurol. Psychiatry. 1958; 79 :475–497. [ PubMed ] [ Google Scholar ]
• Salat DH, van der Kouwe AJW, Tuch DS, Quinn BT, Fischl B, Dale AM, Corkin S. Hippocampus. 2006; 16 :936–945. [ PubMed ] [ Google Scholar ]
• Scoville WB, Milner B. J. Neurol. Neurosurg. Psychiatry. 1957; 20 :11–21. [ PMC free article ] [ PubMed ] [ Google Scholar ]
• Squire LR, Zola-Morgan S. Science. 1991; 253 :1380–1386. [ PubMed ] [ Google Scholar ]
• Steinvorth S, Levine B, Corkin S. Neuropsychologia. 2005; 43 :479–496. [ PubMed ] [ Google Scholar ]
• Tulving E, Schacter DL, Stark HA. J. Exp. Psychol. Learn. Mem. Cogn. 1982; 8 :336–342. [ Google Scholar ]

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Article Contents

Influential case studies, psychosurgery and asylums, temporal lobectomy, controversy, author notes.

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Remembering H.M.: Review of “PATIENT H.M.: A Story of Memory, Madness, and Family Secrets”

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David W. Loring, Bruce Hermann, Remembering H.M.: Review of “PATIENT H.M.: A Story of Memory, Madness, and Family Secrets”, Archives of Clinical Neuropsychology , Volume 32, Issue 4, June 2017, Pages 501–505, https://doi.org/10.1093/arclin/acx041

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Although many influential case reports in neuropsychology exist ( Code, Wallesch, Joanette, & Lecours, 1996 ), there are certain patients who stand out because, based upon the historical zeitgeist in which their brain injuries occurred and the attention that those cases received, their neurobehavioral deficits and circumstances of their injury greatly altered our knowledge of brain-behavior relationships.

Among the most famous of these cases is Phineas Gage, the railroad foreman whose personality dramatically changed following frontal lobe injury in 1848 from an accidental explosion that thrust his tamping iron through his skull. Gage's survival after such a serious injury was a surprise, but Gage's contribution to clinical neuroscience was his significant personality change, aptly described by his physicians with the pithy observation, “Gage was no longer Gage” ( Macmillan, 2000 ). Although his personality changes were well documented soon after the accident, much of Gage's long-term outcome may have been exaggerated for entertainment value ( Macmillan & Lena, 2010 ). Thus, the lasting neurobehavioral effects of Gage's frontal lobe injury and how the deficits may have evolved over time remain clouded in the historical record due to the absence independent scientific characterization.

The second patient is Louis Victor Leborgne, whose expressive language disturbance from a left frontal lobe lesion was described in 1861 by the famous French neurologist Pierre Paul Broca. Monsieur Tan, as he was informally called because “tan tan” was his typical verbal output, retained his capacity to understand commands. The deficits of Monsieur Tan, supported by subsequent cases, demonstrated that language could be fractionated into different components associated with distinct brain regions, and that language was predominately a function of the left brain. Monsieur Tan's contribution, however, was in no small part due to Broca's distinguished reputation as a physician and scientist since localized language effects had been previously described by Jean-Baptiste Bouillard ( Sondhaus & Finger, 1988 ).

The third and most studied of these three cases is patient Henry Molaison (H.M.). H.M. suffered a dense and persistent anterograde amnesia following bilateral medial temporal lobectomy in 1953 to treat intractable epilepsy ( Scoville & Milner, 1957 ). His scientific fame derives from the dramatic demonstration of the critical role that the mesial temporal lobe structures play in learning and memory. Unlike Gage and Monsieur Tan, H.M.’s brain injury was iatrogenic, being an unanticipated adverse event associated with the surgical treatment of his epilepsy. Another important difference is that H.M.’s surgery injury occurred in what can broadly be considered to be the beginning of the modern era of neuroscience ( Shepherd, 2010 ). Thus, his cognitive abilities were subjected to formal characterization with extensive neuropsychological testing over five decades, providing a much richer characterization of his clinical semiology compared to Gage or Monsieur Tan.

H.M.’s amnesia framed how the neuroscience community would eventually conceptualize basic memory mechanisms, beginning with Brenda Milner's early demonstration that multiple memory systems exist such that declarative and procedural memory are readily dissociable ( Milner, 1965 ). Clinically, H.M.’s amnesia meaningfully influenced pre-operative epilepsy surgery protocols across the world. After several additional cases of post-surgical amnesia developed following unilateral temporal lobectomy, it was hypothesized that the functional reserve of the contralateral temporal lobe was insufficient to support the encoding of new memories following resection of the epileptogenic temporal lobe and mesial structures, and multiple methods for characterizing functional hippocampus status were developed ( Milner, 1975 ). What remains poorly reported in standard textbooks, however, is the historical context in which the decision to undergo epilepsy surgery was made, the blurring between experimental clinical techniques and informed consent, and the profound effects on H.M.’s quality of life.

To provide this broad historical context of H.M., Luke Dittrich has published PATIENT H.M.: A Story of Memory, Madness, and Family Secrets ( Dittrich, 2016a ). This is far from a narrative review of H.M.’s contributions to understanding memory, and it is also not a typical biography. However, as the grandson of William Beecher Scoville, MD, the neurosurgeon who performed H.M.’s operation and a prolific practitioner of psychosurgery, Dittrich provides a unique “insider” perspective and captivating description of that era's medical zeitgeist that could not be easily achieved without such a personal relationship. In fact, much of the book does not directly involve H.M.’s life story, but rather, the management of significant psychiatric disease prior to the development of neuroleptics.

Scoville's neurosurgical practice primarily involved surgery for psychiatric indications rather than epilepsy surgery. The early development of psychosurgery's goals is exemplified with a quote from the 19th century physician Dr. Gottleib Burckhardt, who resected undifferentiated brain areas, that illustrates the depersonalization of patients with psychiatric disease: “Mrs. B. has changed from a dangerous and excited demented person to a quiet demented one” (p. 79). It was in late 1935, after listening to the report of operations on two chimpanzees, that Egas Moniz oversaw the first in his series of approximately 20 frontal leucotomies/lobotomies. This series significantly influenced Walter Freeman (neurologist) and James Watts (neurosurgeon) who initially worked together performing prefrontal lobotomies. The distinct approaches to frontal lobotomy developed by Scoville and Freeman also provide a striking contrast in how to best decrease the institutional burden of psychiatric disease. Although Scoville is described as an adventurer who liked expensive sports cars, he was a meticulous neurosurgeon with painstaking preparation before and during all surgical cases. Freeman's enthusiastic efforts to expand the use of frontal lobotomy was reflected by his technique in which an ice pick, inserted through the orbital sockets to a depth of approximately 3 inches, was moved back and forth for frontal disconnection before repeating the procedure on the opposite side. As practiced by Freeman, frontal lobotomy required approximately 15 min to complete, could be performed without a surgeon or an operating room, and multiple procedures could be easily performed in a single day. “Any reasonably competent psychiatrist (could be trained) to perform the ice-pick lobotomy in an afternoon” (p. 151). One can go elsewhere for the complete story of Freeman, his activities and their aftermath, which has been covered by others including the exquisite text by Elliot Valenstein (1986) .

Dittrich's concerns regarding psychiatric therapies during this era are not limited to psychosurgery. His grandmother, Scoville's wife, experienced a breakdown sometime after their marriage, suffered a brittle psychiatric course, and was institutionalized at the Hartford Institute of Living while her husband was director of neurosurgery there and was performing lobotomies at both the Institute of Living and Hartford Hospital. A variety of harsh non-surgical but unproven psychiatric treatments were used that included: (1) Continuous hydrotherapy in which patients were submerged in a tub with only their heads protruding through a small aperture. (2) Pyrotherapy in which patients were placed in a small copper coffin appearing device that, over a repeated treatment period of days, would elevate core temperatures to 105–106 °C. (3) Electric Shock Therapy. In response to patients’ fears about these therapies, treatment names were changed. “Since these treatments produce states of unconsciousness akin to normal slumber … we are adopting the names that are more truly descriptive of these treatments—INSULIN, METRAZOL, and ELECTRIC SLEEP” (p. 73). Karl Pribram, who was head of research at the Institute of Living at that time, claimed that Scoville had performed a frontal leucotomy on his wife, although Dittrich could not independently substantiate that assertion.

A recurring theme throughout PATIENT HM is the concept embodied by the Hippocratic Oath of “ primum non nocer ” (first, do no harm) as it contrasts with “ melius anceps remedium quam nullum” (it is better to do something than nothing). The tension between these approaches lies at the foundation of modern informed consent in which risks and benefits are carefully weighed as part of the decision-making processes prior to treatment initiation or when deciding to participate in clinical research. Informed consent discussion is not restricted to psychosurgery, shock therapies, or H.M. The rationale for informed consent includes the development of surgical treatment for vesicovaginal fistula by J. Marion Sims during the mid-19th century that was conducted on his slaves prior to application to white women, to the U.S. Public Health Service Tuskegee Syphilis Experiment in the 1930s, and the history of the Doctors Trial at Nuremberg after World War II resulting in the Nuremberg Code.

Scoville was a practitioner of psychosurgery rather than epilepsy surgery, and prior to H.M.’s surgery, Scoville had performed multiple bilateral temporal lobectomies for psychiatric indications. Although he describes H.M.’s surgery as an “experimental operation,” he also states that the procedure was considered due to H.M.’s seizure frequency and severity despite adequate medical therapy, and that surgery was “carried out with the understanding and approval of the patient and his family” ( Scoville & Milner, 1957 ).

By the time of H.M.’s surgery in 1953, the first reported series of temporal lobectomies for epilepsy had been published from the Montreal Neurological Institute (MNI) ( Penfield & Flanigin, 1950 ). Dittrich describes the important contributions of Wilder Penfield in epilepsy surgery development that ranged from identification of motor and sensory homunculi to how Penfield established a multidisciplinary and state of the art institute by including neurology, electrophysiology, and neuropsychology colleagues. It was in this context that Penfield hired Brenda Milner. A brief biography of Milner's early life is presented in which she designed psychological aptitude tests at Cambridge University during World War II before moving to Montreal and enrolling at McGill University as a graduate student of Donald Hebb.

Although H.M.’s surgery was not performed at the MNI, Milner's neuropsychological testing of epilepsy surgery patients at the MNI made her arguably the most appropriate individual to characterize H.M.’s memory impairment. The first formal scientific presentation of H.M.’s amnesia was published in 1957 by Scoville and Milner although his “very grave, recent memory loss” was described in 1953 at a meeting of the Harvey Cushing Society ( Scoville, 1954 ). However, the 1957 report also contains formal testing on additional temporal lobectomies performed on “seriously ill schizophrenic patients who had failed to respond to other forms of treatment” (p. 11), two of whom also developed significant amnesia following bitemporal resection. Orbital undercutting was extended to include the medial temporal lobes in the “hope that still greater psychiatric benefit might be obtained” (p. 11). The significant psychiatric disease of these patients decreased clinical awareness of memory change without Milner's formal testing given that “the psychotic patients were for the most part too disturbed before operation for finer testing of higher mental functions to be carried out” (p. 12). Thus, the extent of the memory impairment was unknown due to the significant overlaying psychiatric disease in the non-epilepsy patients on whom Dr. Scoville had performed bitemporal resection prior to H.M.

Scoville was sufficiently enthusiastic about the procedure to travel to teach other surgeons the technique. Interesting is mention of Scoville's trip to Manteno State Hospital, an extremely large psychiatric facility located south of Chicago in Manteno, Illinois. Here faculty from the University of Illinois were performing anterior temporal lobectomies that included hippocampal resection, something not undertaken by Percival Bailey in his series in Chicago. Dittrich mentions another severely amnestic case (D.C.) as an outcome of Scoville's surgery at Mantero, a physician from Chicago with a premorbid IQ of 122. He was evaluated postoperatively with the resulting amnesia, comparable to H.M., confirmed by Brenda Milner. This case was apparently very unsettling to Scoville.

It is impossible to review PATIENT HM without consideration of outside events that occurred after its publication. The New York Times Magazine published a book excerpt on August 3, 2016, beginning with interviews with H.M. illustrating the magnitude and severity of his memory impairment, briefly discussing post-mortem brain ownership disagreements between the University of California at San Diego and Massachusetts Institute of Technology, presenting background material on the tension between research groups surrounding manuscript preparation describing an previously unknown lesion in H.M.’s frontal lobe that was detected at autopsy, and discussing how H.M.’s court-appointed guardian was identified. The excerpt concludes with interview quotations from Dr. Suzanne Corkin, who was the principal investigator of H.M.’s amnesia since 1977 following the death of Hans-Lukas Teuber. Again, in an interesting personal twist, Corkin lived across the street from the Scovilles, and was one of Dittrich's mother's best friends during their childhood and adolescence.

After The Times’ excerpt appeared, MIT and other organizations quickly issued statements disputing Dittrich's assertions and conclusions ( Eichenbaum & Kensinger, 2016 ; MIT News Office, 2016 ). The main points of contention included: (1) allegation that research records were or would be destroyed or shredded, (2) allegation that the finding of an additional lesion in left orbitofrontal cortex was suppressed, and (3) allegation that there was something inappropriate in the selection of (the conservator) as Mr. Molaison's guardian. In addition, a letter signed by over 200 scientists supporting Corkin dated August 5, 2017 was sent to The Times ( DiCarlo et al., 2016 ) asserting that Dittrich's claims were untrue.

Part of the interest in the quick response by the scientific community presumably was that Corkin died on May 24, 2016 prior to the book's publication and was unable to respond to these concerns. While Dittrich (2016b) has directly addressed each of the MIT concerns, their response has nevertheless led many of our colleagues and students to assume that Dittrich's book was incendiary, and whose entire story should not be believed.

While the interested reader will examine both sides of the argument (see Vyse, 2016 ), there is no evidence to suggest that any of Dittrich's factual allegations are wrong. Thus, there are two important points to consider when deciding if this controversy should make otherwise interested individuals pass on reading the book. First, in response to the assertion that research records were shredded, some have suggested Corkin's use of “shredding” was either colloquial or referred to material no longer considered relevant. Corkin is explicit in her description of data shredding in the audio clip of her interview that Dittrich posted ( Dittrich, 2016b ). Certainly, the presence of many files in a storage room says nothing about whether any files had been shredded, particularly since there has never apparently been a comprehensive catalog of the material established. Non-published information can still inform our understanding of H.M.’s clinical course as demonstrated by Dittrich's observation that H.M. had a significant memory impairment prior to surgery, a fact that had not been formally published. Similarly, non-significant findings or “failed experiments” also demonstrate a broader representation of functions either affected or unchanged following surgery. As Dittrich notes, Corkin was a “meticulous investigator, keeping careful notes” (p. 270), and these notes have both scientific and historical value.

H.M.’s legal guardianship merits greater discussion compared to disagreements about scientific ownership and publication disputes, however, which unfortunately are sufficiently common that university committees exist to address such conflicts. Conservatorship, however, is central to this story because it affects the informed consent for H.M.’s research participation, as well as influencing the final disposition of H.M.’s brain after autopsy. Similar to research study reporting standards, the nature of informed consent has evolved over the course of H.M.’s research participation. Consequently, the absence of any conservator or formal consent process early in H.M.’s research participation reflected generally accepted standards at that time. In 1992, an independent conservator was sought for H.M. to mitigate against unintended conflict of interest by H.M.’s investigators, reflecting greater overall awareness of the importance of informed consent.

The eventual conservator was a son of a former landlady of H.M. Dittrich provides evidence that, in contrast to formal court filings, the conservator was not a relative, and that one of H.M.’s relatives was a first cousin sharing H.M.’s last name (Frank Molaison). We will never fully know how the various points are intertwined or even if H.M.’s relatives had been contacted and were not interested in assuming the role of conservator, and part of this controversy is that Corkin's perspective on Dittrich's claims cannot be obtained. Nevertheless, Dittrich's reporting these issues are neither irrelevant nor inappropriate. Careful consideration of H.M.‘s ability to provide informed consent, and how conservatorship is established in circumstances in which research subjects cannot fully consent, will increase awareness of ambiguities that will allow future researchers to confidently ensure full and appropriate consent is obtained prior to research participation.

Most of the book presents a non-controversial narrative, however, and that was not adequately captured by The Times’ excerpt. What we found to be particularly enjoyable in this book is that it provides new details on the contours of H.M.’s life. Prior to H.M.’s death, there were few personal details known to the scientific community, so it should not be surprising that much of this book's appeal is due to its biographical content reporting a variety of details about H.M.’s past. Upon hearing of H.M.’s death, the initial knowledge of his full name was both exciting but then also associated with some sense of guilt and dismay as if suddenly becoming privy to secret information that had been inadvertently revealed. We enjoyed reading about H.M.’s confusion of The Beatles with The Rolling Stones when examining a photograph, but then accurately spelling B-E-A-T-L-E-S rather than beetles, but there are many others throughout the book such as H.M.’s thick New England accent. When asked “Who, or what, is Sue Corkin,” H.M. replied “She was a … well, a senator.” The book also describes frequent angry outbursts including physical harm to himself, which contrasts with the typical H.M. description of his being agreeable and passive, and it is interesting to speculate whether this behavior might have been related to the orbitofrontal damage identified during autopsy. These pieces of personal information help humanize H.M. rather than simply being either a research subject or clinical syndrome. A particularly poignant comment by H.M. was his statement that “every day is alone in itself. Whatever enjoyment I've had, and whatever sorrow I've had” (p. 375).

Despite the controversies that arose after publication of The Times’ excerpt, or perhaps because of them, this book provides a unique glimpse into the blurring of experimental therapy and research during the mid-20th century, motivations for finding treatments for psychiatrically intractable patients prior to the development of neuroleptics, as well as professional interactions and conflicts that may arise in collaborative research settings. Unlike Gage and Monsieur Tan, the depth of clinical research and the modern era in which he lived not only makes H.M. one of the most influential case studies in clinical neuroscience, but also provides one of the most compelling individual stories about how unanticipated surgical effects robbed H.M. of the capacity to form meaningful and lasting relationships with others due to the inability to form new memories. Though clearly not a textbook, and undeniably chatty at times, this is a volume that neuropsychologists at all levels of training and experience, and particularly those with interests in the history of medicine, will enjoy reading and remembering for a long time.

PATIENT H.M: A Story of Memory, Madness, and Family Secrets received the 2017 The PEN/E. O. Wilson Literary Science Writing Award. We thank Kimford J. Meador for his helpful comments on an earlier draft of this review.

Code , C. , Wallesch , C. W. , Joanette , Y. , & Lecours , A. R. ( 1996 ). Classic cases in neuropsychology . New York : Psychology Press .

Google Scholar

Google Preview

DiCarlo , J. J. , Kanwisher , N. , Gabrieli , J. D. E. , Adcock , R. A. , Addis , D. R. , Aggleton , J. P. , et al.  . ( 2016 ). Letter to the Editor of the New York Times Magazine. Retrieved from https://bcs.mit.edu/news-events/news/letter-editor-new-york-times-magazine .

Dittrich , L. ( 2016 b). Questions & Answers about “Patient H.M.” Retrieved frrom https://medium.com/@lukedittrich/questions-answers-about-patient-h-m-ae4ddd33ed9c#.apelhqx85.

Dittrich , L. ( 2016 a). PATIENT H.M.: A story of memory, madness, and family secrets . New York : Random House .

Eichenbaum , H. , & Kensinger , E. ( 2016 ). In defense of Suzanne Corkin. Retrieved from https://www.psychologicalscience.org/observer/in-defense-of-suzanne-corkin#.WKIOVE3rvL8 .

Macmillan , M. ( 2000 ). Restoring Phineas Gage: A 150th retrospective . Journal of the History of Neurosciences , 9 (1), 46 – 66 .

Macmillan , M. , & Lena , M. L. ( 2010 ). Rehabilitating Phineas Gage . Neuropsychological Rehabilitation , 20 (5), 641 – 658 .

Milner , B. ( 1965 ). Visually guided maze learning in man: Effects of bilateral hippocampal, bilateral frontal, and unilateral cerebral lesions . Neuropsychologia , 3 , 317 – 338 .

Milner , B. ( 1975 ). Psychological aspects of focal epilepsy and its neurosurgical management . Advances in Neurology , 8 , 299 – 321 .

MIT News Office ( 2016 ). Faculty at MIT and beyond respond forcefully to an article critical of Suzanne Corkin. Retrieved from http://news.mit.edu/2016/faculty-defend-suzanne-corkin-0809 .

Penfield , W. , & Flanigin , H. ( 1950 ). Surgical therapy of temporal lobe seizures . AMA Archives of Neurology & Psychiatry , 64 (4), 491 – 500 .

Scoville , W. B. ( 1954 ). The limbic lobe in man . Journal of Neurosurgery , 11 , 64 – 66 .

Scoville , W. B. , & Milner , B. ( 1957 ). Loss of recent memory after bilateral hippocampal lesions . Journal of Neurology, Neurosurgery & Psychiatry , 20 , 11 – 21 .

Shepherd , G. M. ( 2010 ). Creating modern neuroscience: The revolutionary 1950s . New York : Oxford University Press .

Sondhaus , E. , & Finger , S. ( 1988 ). Aphasia and the CNS from Imhotep to Broca . Neuropsychology , 2 (2), 87 – 119 .

Valenstein , E. ( 1986 ). Great and desperate cures: The rise and decline of psychosurgery and other radical treatments for mental Illness . New York : Basic Books .

Vyse , S. ( 2016 ). Consensus: Could two hundred scientists be wrong? Retrieved from http://www.csicop.org/specialarticles/show/consensus_could_two_hundred_scientists_be_wrong .

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• The Brain Facts Book

Patient Zero: What We Learned from H.M.

• Published 16 May 2013
• Author Dwayne Godwin
• Source BrainFacts/SfN

Memory is our most prized human treasure. It defines our sense of self, and our ability to navigate the world. It defines our relationships with others – for good or ill – and is so important to survival that our gilled ancestors bear the secret of memory etched in their DNA. If you asked someone over 50 to name the things they most fear about getting older, losing one’s memory would be near the top of that list. There is so much worry over Alzheimer’s disease, the memory thief, that it is easy to forget that our modern understanding of memory is still quite young, less than one, very special lifespan.

Meet the Patient Zero of memory disorders, H.M.

H.M. was the pseudonym of Henry Molaison, a man who was destined to change the way we think about the brain. Permanent Present Tense: The Unforgettable Life of the Amnesic Patient H.M. is a touching, comprehensive view of his life through the eyes of a researcher who also, in a sense, became part of his family.

The prologue opens with a conversation between the author, Suzanne Corkin, and Molaison in 1992. It reads a bit like a first meeting of two strangers, but then Corkin reveals a jarring truth: this meeting was one of many similar encounters they’d had over 30 years.

By now, if you’re interested in learning and memory you probably know the basics of Henry Molaison’s story. He had epilepsy from an early age that was thought to be acquired through head trauma from a bike accident (though apparently family members also had epilepsy). His surgeon, William B. Scoville (who in a remarkable twist, was a childhood neighbor of Suzanne Corkin) removed Henry’s hippocampus and amygdala in both hemispheres of his brain, in an attempt to control his seizures.

The results of the surgery are legendary. While Henry’s seizures were controlled, he suffered a type of profound anterograde amnesia that prevented him from encoding new memories, but spared certain details of his life leading up to the surgery. Henry would have no memory of those he worked with from day to day, or of new information he might encounter. The book’s title, “Permanent Present Tense”, describes his zen-like existence within the thirty or so seconds around the present moment, which was the limit of Henry’s short term memory.

If this book were a movie or video game, it would be said to be full of “Easter eggs”. There are vignettes and bits of unexpected information that add rich historical context to the state of knowledge in Molaison’s time. These include a digression on the history of neurosurgery, including the gruesome history of lobotomies and the advances brought to the field of neurosurgery by Wilder Penfield. In many ways, H.M.’s legend is a product of a unique scientific lineage – Scoville owed much to Penfield, who in turn trained under Charles Sherrington (he who gave “synapse” to the neuroscience lexicon), and Brenda Milner, who trained under Donald Hebb (who spawned our current notion of activity-dependent plasticity, embodied by the phrase, “cells that fire together wire together”).

The book also reminds us that H.M. was not the first amnesic patient produced through neurosurgical interventions to treat intractable epilepsy, but he was by far the most studied. The book conveys a sense of wonder at the accomplishments of scientists and physicians, charting terra incognita with scalpels, electrical probes and psychological test batteries.

Corkin recounts Henry Molaison’s early life, including key events - like a childhood plane ride that Henry remembered after his surgery - with gentle but thorough prose. Some of these details come from personal conversations with Henry, while others are the result of careful reporting and research.

The book is an accessible master class in learning and memory, with details and key milestones culled from Corkin’s decades of experience as a memory researcher. The details are not so burdensome as to be esoteric, nor so simple as to be trivial. The book gives only a brief overview of the growing field of knowledge about the cellular mechanisms supporting learning and memory (which might be lost on a casual reader), but this is wisely offset by the details of functional anatomy gleaned from Henry and other patients, and a solid explanation of how we encode, store and retrieve memories.

A light, scholarly tone is maintained throughout the book, but it occasionally brushes up against the deeply personal. It’s difficult to hear Henry’s story and not wonder (or actually, worry) about how it was to live as Henry lived, trapped in the moment. Corkin is reassuring on this point:

“When we consider how much of the anxiety and pain of daily life stems from attending to our long-term memories and worrying about and planning for the future, we can appreciate why Henry lived much of his life with little stress…in the simplicity of a world bounded by thirty seconds.”[p. 75].

In other words, the very thing that might cause Henry to fret about his condition was missing. Henry’s tragedy, it seems, is in the mind of the beholder. Another interesting passage concerns Henry’s moods – which were usually happy and content, but could occasionally be sad or uneasy. This is interesting given the removal during his surgery of a major part of his emotional processing circuitry of the brain, called the amygdala.

Henry Molaison’s anterograde amnesia was practically absolute. However, something not often noted is that he would occasionally surprise those studying him by recalling something he should not be able to remember - for example, colored pictures, or details of celebrities he had heard about after his surgery. Corkin reasons that a bit of spared medial temporal lobe may explain these moments.

Henry was amnesic, but he was not without memory. Through careful behavioral testing, various types of memory function could be uncovered, including recognition memory for having seen images that could persist for months. Corkin suggests that this “memory for the familiar” may have been of some comfort as he navigated what would have otherwise been a confusing experience of reality. New technologies like computers, for example, could be incorporated into his view of the world and did not appear to be jarring to him as would be expected if his capacity for recognizing the familiar did not exist.

Another key discovery from Henry was the finding that he had retained the ability to form non-declarative memories, which took the form of improvement in motor skills. This separate memory system depended on regions of the basal ganglia and motor cortex, which were spared in Henry’s surgery. Testing could improve his performance in the motor task, but his impaired declarative memory system didn’t allow him to remember taking the tests – he could be surprised by his own improvement. Along with his simple recognition memory, motor memory helped smooth challenges Henry faced as he aged, such as learning to use a walker.

Other forms of memory in which Henry showed improvement were in picture completion, where he was able to identify a picture from fragments over a series of sessions, and priming, where previously presented words could prime recognition on presenting fragments of the words. And while Henry is best known for anterograde amnesia, and is sometimes portrayed as having intact memories of things and events before the surgery, he also possessed a partial retrograde amnesia, especially for autobiographical events that happened two years before the surgery - he had only fragmented memories from before that two year window.

Did Henry Molaison have a sense of self? While his was not a fully integrated personality, he possessed “beliefs, desires and values” and seemed capable of a full set of emotions – even without his amygdalae. His view of his own appearance did not seem to cause him distress, even though his estimate of his own age could vary widely. His impairment prevented him from formulating future plans. His basic decency shines through the narrative.

Henry died in 2008 at the age of 82. His brain was scanned postmortem, and extracted for further anatomical analysis . Coming full circle from one of his remaining childhood memories of his first ride, Corkin describes her last wistful goodbye to Henry’s brain as it was conveyed by his final plane ride back to the west coast, where his brain was sliced up into thin sections for new studies. Perhaps the most documented and studied research subject in neuroscience continues to provide vast amounts of data to further our knowledge.

Henry once remarked about his testing, of which he never seemed to become bored since he carried little from one session to the next: “It’s a funny thing – you just live and learn.” He then went on to provide a poignant turn in the familiar phrase: “I’m living, and you’re learning.”

Though he’s no longer living, we’re still learning from Henry.

Permanent Present Tense is a rare look at an amazing mind, whose study formed the basis of our modern science of memory.

Corkin, Suzanne. Permanent Present Tense: The Unforgettable Life of the Amnesic Patient, H.M. (Basic Books) May 14, 2013 | ISBN-10: 0465031595 | ISBN-13: 978-0465031597

Update 6/7/2013: NPR interview with Suzanne Corkin on H.M .

Update 1/30/2014: Report on anatomical and histological findings from Henry Molaison: Postmortem examination of patient H.M.’s brain based on histological sectioning and digital 3D reconstruction . J Annese, NM Schenker-Ahmed, H Bartsch, P Maechler, C Sheh, N Thomas, J Kayano, A Ghatan, N Bresler, MP Frosch, R Klaming & S Corkin. Nature Communications 5, Article number: 3122

Update 7/6/2016: Statement on informed consent transmitted to me by Suzanne Corkin

About the Author

Dwayne Godwin

Dwayne Godwin is a Professor of Neurobiology and Neurology at the Wake Forest University School of Medicine, where he studies epilepsy, sensory processing, withdrawal and PTSD. He coauthors a comic strip on brain topics for Scientific American Mind .

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H.M.; Also the Case of H.M., Molaison, Henry (1926–2008)

• Reference work entry
• First Online: 01 January 2018
• pp 1629–1631
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• Amy Alderson 4  

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Landmark Clinical, Scientific, and Professional Contributions

Investigations of Henry Molaison’s (HM) neurocognitive functioning following his surgical intervention have revolutionized our understanding of learning and memory processes. HM’s specific surgical intervention and associated cognitive impairments provided information not only about differential memory activities but also about the neural substrates involved in the mediation of these processes. Investigations of the alterations in HM’s memory led to a landmark paper by Brenda Milner, a psychologist working with HM, and William Scoville, his neurosurgeon. The paper, entitled Loss of recent memory after bilateral hippocampal lesions , was published in the Journal of Neurology, Neurosurgery, and Psychiatry in 1957; it brought about a sea change in the understanding of the neural substrates of memory. This paper has been cited more than 1800 times since its initial publication.

In this landmark paper, as well as in many others...

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References and Readings

Corkin, S. (2002). Whats new with amnesic patient H.M.? Nature Reviews Neuroscience, 3 , 153–160.

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Ogden, J. A. (2005). Fractured minds . New York: Oxford University Press.

Google Scholar  

Scoville, W. B. (1968). Amnesia after bilateral mesial temporal-lobe excision: Introduction to case H.M. Neuropsychologica, 6 , 211–213.

Article   Google Scholar  

Scoville, W. B., & Milner, B. (1957). Loss of recent memory after bilateral hippocampal lesions. Journal of Neurology, Neurosurgery, and Psychiatry, 20 , 11–21.

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Scoville, W. B., & Milner, B. (2000). Loss of recent memory after bilateral hippocampal lesions. Journal of Neuropsychiatry and Clinical Neuroscience, 12 (1), 103–113.

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Amy Alderson

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Alderson, A. (2018). H.M.; Also the Case of H.M., Molaison, Henry (1926–2008). In: Kreutzer, J.S., DeLuca, J., Caplan, B. (eds) Encyclopedia of Clinical Neuropsychology. Springer, Cham. https://doi.org/10.1007/978-3-319-57111-9_622

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A New Origin Story for H.M., One of Psychology’s Most Famous Case Studies

You’re familiar with Henry Molaison, even if you don’t recognize his name. You likely know him by his initials: He is H.M., an epileptic man who became a famous amnesiac patient after an unprecedented brain surgery done by the august neurosurgeon William Scoville. H.M.’s story is a mainstay in undgrad psychology courses, and it’s also inspired books and movies, not to mention hundreds of scientific studies — all of which makes one wonder, at first, why a new book on the subject is needed. “I’m certainly not the first person who has written about H.M., and I’m certainly not the last,” the journalist Luke Dittrich tells me, a few days before the publication of his first book, Patient H.M. : A Story of Memory, Madness, and Family Secrets . “But one of the things I’m trying to accomplish is to take back H.M.’s story, or at least give an alternate telling, that is wrested in a certain sense from the people who have already told it.” Dittrich offers a perspective on this famed case that no one else can: Scoville, the surgeon who created Patient H.M., was his grandfather.

A quick overview of H.M.’s story, in case it’s been a while since you took Psych 101: In the 1950s, H.M. was a young man living with his parents in modest circumstances in Connecticut; he had such severe epilepsy that he could live only the most stripped-down existence, barely able to function at the most menial of jobs. In 1953, Scoville suggested the unprecedented step of removing a good deal of H.M.’s temporal lobes — the area of the brain just behind the ears that contains what’s known as the limbic system, often thought to be fundamental to the brain’s ability to manufacture emotion — including most of his hippocampus and part of his amygdala. H.M. and his parents said yes.

They said yes, but they didn’t know — no one knew — that the regions of the brain Scoville intended to remove were, in fact, integral to the brain’s ability to form new memories. After his surgery, H.M. was reborn in Hartford, Connecticut, as the ultimate amnesiac, unable to remember events from more than a few minutes before. He was reduced to short-term memory, lost in a maze of the present tense. His amnesia was considered “pure” — that is, manufactured with the precision of the surgeon’s scalpel, with his intellect left undimmed (indeed, possibly even slightly improved). Over the next 50 years, his case would fuel hundreds of studies by researchers eager to solve the mystery of how memory works in the brain. The fascination went beyond science: H.M.’s story has inspired books and movies, all depicting the man whose profound amnesia left him suspended in his own distorted chronology, uncertain of whether his own father was alive or dead, who was the president of the United States, or even his own age. (His estimates could be off by decades.) Until the end of H.M.’s life, Dr. Scoville would loom as the ultimate authority figure. “Henry,” a nurse at his assisted-living home might say, “Dr. Scoville insists that you take your meds right now.” The tactic was effective even long after Scoville’s death.

At 43, Scoville’s grandson is a seasoned magazine writer, for Esquire and other publications, yet it took him more than five years to complete his sprawling book. Dittrich’s account raises entirely new questions about the way in which the research on H.M. was conducted — and about the conclusions that have long been incorporated into our understanding of memory. In a café in Washington, D. C., where we meet for lunch, Dittrich — tall, lanky, and recovering from his first NPR interview — is quick to say that he had reservations about digging into this chapter of his family history. Indeed, his is, in some sense, a strange legacy to claim. His grandfather performed the second-highest number of lobotomies in American history. Yet one thing Dittrich’s book does so effectively is to lay out the context which enabled “psychosurgery” to become acceptable, even mainstream.

It started in Switzerland. In 1892, the psychiatrist Dr. Gottlieb Burckhardt longed to find a physical cure for mental illness and, over the next seven years, operated on six patients, cutting out parts of their brains almost at random. “Two of them died, two became epileptic, and one committed suicide,” Dittrich notes. The European medical Establishment rejected Burckhardt’s project with disgust, but by the 1930s, a surgical cure for mental illness was again attempted, this time by the Portugese neuroanatomist Egas Moniz, who targeted, specifically, the brain’s frontal lobes. At the same time, experiments done on monkeys and chimpanzees in the United States — most notably by John Fulton at Yale — revealed that cutting through swathes of frontal-lobe brain matter led to docile, placid creatures, lending a kind of scientific underpinning to the human experimentation. In a breathtakingly short amount of time, the American public embraced psychosurgery as a treatment for the mentally ill. Dittrich writes that the American press embraced the new procedure, and articles appeared bearing such headlines as “Wizardry of Surgery Restores Sanity to Fifty Raving Maniacs.”

In the following years, as the lobotomy became more and more widespread, some neurosurgeons hewed to the most conservative applications of the procedure — surgeons like Wilder Penfield, at McGill, who limited his cuts only to the most established parameters — while others, like Dittrich’s grandfather, felt a great deal less inhibited. When it came to the brain, still so little understood, men like Scoville considered themselves explorers, pioneers, charging forth into uncharted territory with a very real desire to plant their flags, even at steep human costs. Scoville in particular had been an ardent believer in psychosurgery from his early days of practicing it. “I am more impressed with psychosurgery every year,” he said, in 1970, after decades of performing the surgeries. “I wonder why more people don’t have it done.” Such was his faith that he continued to perform them into his 70s, long after they had fallen out of favor. Dittrich remembers his grandfather as charismatic and larger than life, the mythic family figure, with a passion for sports cars and reckless driving. But he remains a kind of cipher, a figure of deep moral ambiguity, even after Dittrich’s long attempt to understand.

One of the revelations of Dittrich’s book is personal: His grandmother, Emily Scoville, a.k.a. Bambam, was admitted in 1944 to the ominously named Institute of Living in Hartford, Connecticut, after having a nervous breakdown as a young wife and mother. At the asylum, she was subjected to the harsh treatments of the day — for example, having her body temperature grossly manipulated in icy baths, or, on other days, in scalding heat, for hours on end. Neither hydrotherapy nor pyretotherapy seemed to help her very much. Her husband was affiliated with the Institute of Living, listed as “consulting staff.” He would write to a friend that all of his work in the years to follow, honing his surgical skills on the brains of the mentally unwell, was for “E’s sake.” “If it hadn’t been for my grandmother’s mental illness, there’s an argument to be made that Patient H.M. would never have happened,” Dittrich tells me.

The surprises in Dittrich’s narrative do not end with his family; Dittrich’s reporting casts a new, rather harsh light on H.M.’s treatment as a research subject — and throws into question some of the scientific findings that we’ve long understood to be solid. Indeed, the lessons that have emerged from H.M.’s plight have, more than any other single source, informed our understanding of memory. For instance, it is because of H.M. that we know that different kinds of memories are stored in different areas of the brain. Procedural memories, like how to ride a bike, drive a car, or turn a combination lock (to the right, to the left, to the right, just so) — skills we’ve internalized so deeply we no longer give them full conscious attention — are laid out in the brain separately from episodic memories, those mini movies we play in our head when we recall the specific moments of our life, like a kiss or a fight or yesterday’s dinner. H.M. was able to form new procedural memories, growing increasingly masterful on certain tricky tasks, like tracing a star while looking only at its reflection in a mirror. (Who knew, but this is famously difficult to do.) H.M. quickly improved on the star-mirror task, even without remembering ever having done it before. But he could never again form new episodic memories — and, the research suggests, he essentially lost the episodic memories that came before his surgery, too, retaining only the facts of his life, without its lived richness. He could remember where a birthday party had taken place, but not the party   itself.

It was Suzanne Corkin, a neuropsychologist at MIT , who conducted much of this research. Decades’ worth of it. H.M. spent most of his post-surgical life traveling between his assisted-living home in Bickford, Connecticut, and Corkin’s lab at MIT , where he was scrutinized by an ever-changing cast of grad students and researchers, given an endless battery of tests and tasks. In his reporting process, Dittrich ran up against the same phenomenon that many others have also encountered: Corkin controlled access to H.M. as if to a diamond mine. Far from practicing openness and transparency, the supposed values of science, she established herself as a Cerberus figure, ferociously guarding the patient who had made her famous. When Dittrich attempted to meet H.M., for instance, Corkin refused him access. When he wanted to include a photograph of H.M. in his book, he found that Corkin had assumed control of all of that material as well — and she demanded $850 from Dittrich for use of the photo. (He declined.) When Dittrich was finally able to interview Corkin herself, she told him rather nonchalantly that she had shredded much of the original data gathered from decades of H.M. research. “The papers exist, so you don’t need the data,” he recalls her explaining.

Yet some of the original data that Dittrich did manage to turn up contradicts the story that Corkin liked to tell. For example, Dittrich discovered psychological questionnaires that had been given to H.M. in the 1980s. Filling out the Beck Depression Inventory in 1982, H.M. circled such statements as: “I feel that the future is hopeless and that things cannot improve.” And: “I feel that I am a complete failure as a person.” Yet, as Dittrich writes, Corkin herself said that H.M. ’s test results showed “no evidence of anxiety” or depression. Indeed, Corkin liked to describe H.M. as being a kind of walking, talking example of Buddhist enlightenment, a man unafflicted by the burden of his past, unable to be anything but present in the moment. “I think there’s something almost like the medieval priesthood, like, only we can read the Bible and tell you what it means,” Dittrich tells me, reflecting on Corkin’s behavior. “I think she felt she was the ultimate interpreter of H.M. and throwing his data out into the world for just anybody to look at would be troubling to her. Ultimately, it allows her to control his narrative — forever.”

When H.M. died, in 2008, his brain was whisked away to be dissected and immortalized in digital form by the neuroanatomist Jacopo Annese, at the University of California, San Diego. Dittrich recounts a deeply unbecoming chapter that ensued, involving a protracted power struggle and legal threats from Corkin and MIT , and ultimately resulting in Annese’s forfeiting the brain — as well as his job. Yet one of the discoveries that Annese made while in possession of H.M.’s brain was a lesion in the frontal lobe that had never been mentioned or documented before. Indeed, one of the great claims of H.M.’s case was that his frontal lobes — the brain’s chief executive, so to speak — were intact, and that Scoville’s surgical cuts had been limited to the temporal lobes, allowing researchers to correlate specific aspects of memory to those specific temporal structures in the brain. It’s not at all clear exactly what the presence of a frontal-lobe lesion might complicate about the story of H.M. Dittrich himself makes no claims to understand the potential rethinking such a lesion might require. “For me, the frontal lesion adds another dimension to Henry’s story,” Dittrich says. “It raises the sort of questions that make the destruction of the raw data in his case so tragic.” For her part, Corkin, upon learning of the discovery of the lesion, argued that it must have been made posthumously, during the dissection process.

Corkin, who died a few months ago, never read Dittrich’s account of the case that defined her professional life. It is an astonishing version of a story that began long before H.M.’s fateful surgery, in 1953, one that has been told and retold countless times since, new details continuing to surface, new implications to consider, new contradictions to reconcile. No doubt, there are still more to come.

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H.m.'s brain and the history of memory.

Brian Newhouse

In 1953, radical brain surgery was used on a patient with severe epilepsy. The operation on "H.M." worked, but left him with almost no long-term memory. H.M. is now in his 80s. His case has helped scientists understand much more about the brain.

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Scoville and Milner (1957)

Last updated 22 Mar 2021

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Effect of hippocampal damage on memory.

Background information: Scoville performed experimental surgery on H.M.’s brain to stop the severe epileptic seizures he had been suffering since a fall off his bicycle many years previously. Specifically, he removed parts of HM's temporal lobes (part of his hippocampus along with it). The seizures reduced drastically but H.M. suffered from amnesia for the rest of his life. Milner, who was a PhD student of Scoville’s, followed up the surgery with cognitive testing for fifty years after the original operation. Hers is a cognitive longitudinal case study of H.M.’s anterograde (after the surgery) and partial retrograde (before the surgery) amnesia. The biological part of the H.M. study is the correlation between the brain damage and the amnesia, which was assumed in the 1950s, and not verified until later brain scans in the 1990s (see Corkin, 1997)

Aim: In 1953 Scoville performed surgery on the then 27-year-old H.M. to cure him of his epileptic seizures. [Note: this is a surgical procedure – it only became a study later when the memory damage was noted].

Method: The surgery involved what was called a partial medial temporal lobe resection. Scoville removed 8 cm of brain tissue from the anterior two thirds of the hippocampus, and believed he “probably destroyed …. the uncus and amygdala” as well (Scoville and Milner, 1957). Once the extent of the memory loss was realised, Scoville and Milner wrote about this, along with the results from this type of surgery on nine other patients, in a prominent neurosurgical journal, and Milner started her cognitive studying of H.M.

Results: H.M. lost the ability to form new memories. This is called anterograde amnesia. He could do a task, and even comment that it seemed easier than he expected, without realising that he had done it hundreds of times before. His anterograde procedural memory was totally affected. He also lost his memory for events that had happened after his surgery: he could not remember moving house, nor that he had eaten a meal thirty minutes previously. He had also suffered some retrograde amnesia of events preceding the surgery, such as the death of his uncle three years before. However, his early childhood memories remained intact. His intelligence also remained as before, at slightly above average.

Conclusion: The surgery to remove part of the hippocampus, the uncus and the amygdala resulted in total anterograde amnesia and partial retrograde amnesia.

Evaluation:

This is the assumption, based on the results with other patients as well as H.M. In the absence at that time of brain-scanning equipment, other possibilities were also present. The high doses of anti-epileptic drug he was taking before, and the lower doses after the surgery, may have resulted in some memory loss. Also, so far as we can see, no memory tests were conducted on H.M. before the surgery, and the initial memory loss was largely reported by his mother, with whom he lived.

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Who Was H.M.? Inside The Mind Of The Amnesiac Who Revolutionized Neuroscience

By Suzanne Corkin

Posted on May 29, 2013 6:30 PM EDT

My friend’s father was a neurosurgeon. As a child, I had no idea what a neurosurgeon did. Years later, when I was a graduate student in the Department of Psychology at McGill University, this man reentered my life. While reading articles on memory in medical journals, I came across a report by a doctor who had performed a brain operation to cure a young man’s intractable epilepsy. The operation caused the patient to lose his capacity to establish new memories. The doctor who coauthored the article was my friend’s father, William Beecher Scoville. The patient was Henry.

This childhood connection to Henry’s neurosurgeon made reading about the “amnesic patient, H.M.” more compelling. Later, when I joined Brenda Milner’s laboratory at the Montreal Neurological Institute, Henry’s case fell into my lap. For my PhD thesis, I was able to test him in 1962 when he came to Milner’s lab for scientific study. She had been the first psychologist to test Henry after his operation, and her 1957 paper with Scoville, describing Henry’s operation and its awful consequences, revolutionized the science of memory.

I was trying to expand the scientific understanding of Henry’s amnesia by examining his memory through his sense of touch, his somatosensory system. My initial investigation with him was focused and brief, lasting one week. After I moved to MIT, however, Henry’s extraordinary value as a research participant became clear to me, and I went on to study him for the rest of his life, forty-six years. Since his death, I have dedicated my work to linking fifty-five years of rich behavioral data to what we will learn from his autopsied brain.

When I first met Henry, he told me stories about his early life. I could instantly connect with the places he was talking about and feel a sense of his life history. Several generations of my family lived in the Hartford area: my mother attended Henry’s high school, and my father was raised in the same neighborhood where Henry lived before and after his operation. I was born in the Hartford Hospital, the same hospital where Henry’s brain surgery was performed. With all these intersections in our backgrounds and experiences, it was interesting that when I would ask him whether we had met before, he typically replied, “Yes, in high school.” I can only speculate as to how Henry forged the connection between his high-school experience and me. One possibility is that I resembled someone he knew back then; another is that during his many visits to MIT for testing, he gradually built up a sense of familiarity for me and filed this representation among his high-school memories.

Henry was famous, but did not know it. His striking condition had made him the subject of scientific research and public fascination. For decades, I received requests from the media to interview and videotape him. Each time I told him how special he was, he could momentarily grasp, but not retain, what I had said.

The Canadian Broadcasting Corporation recorded our 1992 conversation for two radio programs, one devoted to memory, the other to epilepsy. A year earlier, Philip Hilts had written an article about Henry for the New York Times, and later made him the focus of a book, Memory’s Ghost.

Scientific papers and book chapters were written about Henry, and his case is one of the most frequently cited in the neuroscience literature. Open any introductory psychology textbook and you are likely to find somewhere in its pages a description of a patient known only as H.M., next to diagrams of the hippocampus and black-and-white MRI images. Henry’s disability, a tremendous cost to him and his family, became science’s gain.

Henry would have been proud to know how much his tragedy has benefited science and medicine.During his life, the people who knew Henry kept his identity private, always referring to him by his initials. When I gave lectures about Henry’s contributions to science, I always encountered intense curiosity about who he was, but his name was revealed to the world only after his death in 2008.

Over the course of decades, during which I worked with Henry, it became my mission to make sure that he is not remembered just by brief, anonymous descriptions in textbooks. Henry Molaison was much more than a collection of test scores and brain images. He was a pleasant, engaging, docile man with a keen sense of humor, who knew that he had a poor memory and accepted his fate. There was a man behind the initials, and a life behind the data. Henry often told me that he hoped that research into his condition would help others live better lives. He would have been proud to know how much his tragedy has benefited science and medicine.

Memory is an essential component of everything we do, but we are not consciously aware of its scope and importance. We take memory for granted. As we walk, talk, and eat, we are not aware that our behavior stems from information and skills that we previously learned and remembered. We rely constantly on our memory to get us through each moment and each day. We need memory to survive—without it, we would not know how to clothe ourselves, navigate our neighborhoods, or communicate with others. Memory enables us to revisit our experiences, to learn from the past, and even to plan what to do in the future. It provides continuity from moment to moment, morning to evening, day to day, and year to year.

Through Henry’s case, we gained insights that allowed us to break memory down into many specific processes and to understand the underlying brain circuits. We now know that when we describe what we had for dinner last night, or recite a fact about European history, or type a sentence on a keyboard without looking at the keys, we are accessing different types of memory stored in our brains.

Henry helped us understand what happens when the ability to store information is missing. He retained much of the knowledge he had acquired before his operation, but in his daily life afterward, he depended heavily on the memories of those around him. His family members, and later the staff at his nursing home, remembered what Henry had eaten that day, what medications he needed to take, and whether he needed a shower. His test results, and medical reports, and the transcripts of his interviews, helped preserve information about his life that he could not retain. Of course, none of these resources could substitute for the capacities Henry had lost. For memory does more than just help us survive—it influences our quality of life and helps shape our identity.

Excerpted with permission from Permanent Present Tense: The Unforgettable Life of the Amnesic Patient, H.M. _ by Suzanne Corkin. Available from Basic Books, a member of The Perseus Books Group. Copyright © 2013._

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Science News

Famous brain surgery patient h.m. retained a chunk of hippocampus.

Amnesia probably due to the loss of other regions, connections

MEMORIES ON ICE  Embedded in a frozen gelatin block, Henry Molaison’s brain is about to be sliced and imaged.

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By Laura Sanders

January 28, 2014 at 6:24 pm

After a brain surgeon accidentally took away his memory in 1953, 27-year-old Henry Molaison became one of the most informative cases in psychology. For the rest of his life, the patient known as H.M. donated time to scientists who used the tragedy to study his amnesia. Now, five years after his death, Molaison is still teaching scientists about how the brain makes and stores memories.

A detailed analysis of Molaison’s postmortem brain, generously donated to scientists, reveals a surprising amount of brain tissue in the memory-forming structure known as the hippocampus, scientists report January 28 in Nature Communications . This result shows that Molaison’s severe deficits can’t be pinned exclusively on the loss of the hippocampus, as some scientists previously thought, says neuroscientist Howard Eichenbaum of Boston University, who wasn’t involved in the study.

To ease Molaison’s frequent and severe seizures, surgeon William Beecher Scoville attempted to remove parts of the medial temporal lobe, which includes the hippocampus and other nearby regions. The procedure calmed the seizures but left Molaison largely unable to form new memories. As scientists realized they could link Molaison’s impairments to his drastically altered brain, patient H.M. began to show up in a growing number of research papers.

“The studies on H.M. began the present era of research on how the brain supports memory,” Eichenbaum says.

Because of Molaison’s importance to memory research, Jacopo Annese of the Brain Observatory at the University of California, San Diego and colleagues decided to study Molaison’s brain after his death using a technique that provides a level of detail surpassing methods used on living brains.

About a year after Molaison died, his brain, fixed in formalin, was flown to the Brain Observatory. There, scientists froze it, sliced it into 2,401 paper-thin wisps and photographed them. With these images, Annese and colleagues created a 3-D model of Molaison’s brain.

Scoville’s postsurgical drawings indicated that the entire hippocampus and nearby structures on both sides of the brain had been removed. The new 3-D model showed otherwise.

Molaison retained a surprisingly large amount of what appeared to be healthy hippocampus, the team found. The lingering tissue was the back end of the hippocampus, where the structure curved up toward the top of the head. Scoville may have missed this bit because the suction tube he used to remove brain tissue didn’t follow the bend, Annese proposes. MRI scans from when Molaison was alive revealed some hippocampal tissue, but not as much as the current study finds. Those scans lacked the anatomical precision of the newer method, Annese says.

Because Molaison retained some hippocampus and yet suffered from severe amnesia, other brain structures were probably needed for his memory, Eichenbaum says. Molaison lacked a brain region called the entorhinal cortex, which serves as a signal relay station between the hippocampus and the rest of the brain. The missing entorhinal cortex probably had a big role in Molaison’s impairment, Eichenbaum says.

Comparing Molaison’s memory deficits with those of people known to lack just the hippocampus might help scientists tease apart the jobs of the various brain structures involved in memory, Eichenbaum says. 

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Psychology’s 10 greatest case studies – digested

These ten characters have all had a huge influence on psychology and their stories continue to intrigue each new generation of students. What’s particularly fascinating is that many of their stories continue to evolve – new evidence comes to light, or new technologies are brought to bear, changing how the cases are interpreted and understood. What many of these 10 also have in common is that they speak to some of the perennial debates in psychology, about personality and identity, nature and nurture, and the links between mind and body.

Phineas Gage

One day in 1848 in Central Vermont, Phineas Gage was tamping explosives into the ground to prepare the way for a new railway line when he had a terrible accident. The detonation went off prematurely, and his tamping iron shot into his face, through his brain, and out the top of his head.

Remarkably Gage survived, although his friends and family reportedly felt he was changed so profoundly (becoming listless and aggressive) that “he was no longer Gage.” There the story used to rest – a classic example of frontal brain damage affecting personality. However, recent years have seen  a drastic reevaluation  of Gage’s story in light of new evidence. It’s now believed that he underwent significant rehabilitation and in fact began work as a horse carriage driver in Chile. A  simulation of his injuries  suggested much of his right frontal cortex was likely spared, and  photographic evidence  has been unearthed showing a post-accident dapper Gage. Not that you’ll find this revised account in many psychology textbooks:  a recent analysis  showed that few of them have kept up to date with the new evidence.

Henry Gustav Molaison (known for years as H.M. in the literature to protect his privacy), who died in 2008, developed severe amnesia at age 27 after undergoing brain surgery as a form of treatment for the epilepsy he’d suffered since childhood. He was subsequently the focus of study by over 100 psychologists and neuroscientists and he’s been mentioned in over 12,000 journal articles! Molaison’s surgery involved the removal of large parts of the hippocampus on both sides of his brain and the result was that he was almost entirely unable to store any new information in long-term memory (there were some exceptions – for example, after 1963 he was aware that a US president had been assassinated in Dallas). The extremity of Molaison’s deficits was a surprise to experts of the day because many of them believed that memory was distributed throughout the cerebral cortex. Today, Molaison’s legacy lives on: his brain was carefully sliced and preserved and turned into a 3D digital atlas and his life story is reportedly due to be turned into a feature film based on the book researcher Suzanne Corkin wrote about him:  Permanent Present Tense, The Man With No Memory and What He Taught The World .

Victor Leborgne (nickname “Tan”)

The fact that, in most people, language function is served predominantly by the left frontal cortex has today almost become common knowledge, at least among psych students. However, back in the early nineteenth century, the consensus view was that language function (like memory, see entry for H.M.) was distributed through the brain. An eighteenth century patient who helped change that was Victor Leborgne, a Frenchman who was nicknamed “Tan” because that was the only sound he could utter (besides the expletive phrase “sacre nom de Dieu”). In 1861, aged 51, Leborgne was referred to the renowned neurologist Paul Broca, but died soon after. Broca examined Leborgne’s brain and noticed a lesion in his left frontal lobe – a segment of tissue now known as Broca’s area. Given Leborgne’s impaired speech but intact comprehension, Broca concluded that this area of the brain was responsible for speech production and he set about persuading his peers of this fact – now recognised as a key moment in psychology’s history. For decades little was known about Leborgne, besides his important contribution to science. However, in a paper published in 2013, Cezary Domanski at Maria Curie-Sklodowska University in Poland uncovered new biographical details, including the possibility that Leborgne muttered the word “Tan” because his birthplace of Moret, home to several tanneries.

Wild Boy of Aveyron

The “Wild boy of Aveyron” – named Victor by the physician Jean-Marc Itard – was found emerging from Aveyron forest in South West France in 1800, aged 11 or 12, where’s it’s thought he had been living in the wild for several years. For psychologists and philosophers, Victor became a kind of “natural experiment” into the question of nature and nurture. How would he be affected by the lack of human input early in his life? Those who hoped Victor would support the notion of the “noble savage” uncorrupted by modern civilisation were largely disappointed: the boy was dirty and dishevelled, defecated where he stood and apparently motivated largely by hunger. Victor acquired celebrity status after he was transported to Paris and Itard began a mission to teach and socialise the “feral child”. This programme met with mixed success: Victor never learned to speak fluently, but he dressed, learned civil toilet habits, could write a few letters and acquired some very basic language comprehension. Autism expert Uta Frith believes Victor may have been abandoned because he was autistic, but she acknowledges we will never know the truth of his background. Victor’s story inspired the 2004 novel  The Wild Boy  and was dramatised in the 1970 French film  The Wild Child .

Nicknamed ‘Kim-puter’ by his friends, Peek who died in 2010 aged 58, was the inspiration for Dustin Hoffman’s autistic savant character in the multi-Oscar-winning film  Rain Man . Before that movie, which was released in 1988, few people had heard of autism, so Peek via the film can be credited with helping to raise the profile of the condition. Arguably though, the film also helped spread the popular misconception that giftedness is a hallmark of autism (in one notable scene, Hoffman’s character deduces in an instant the precise number of cocktail sticks – 246 – that a waitress drops on the floor). Peek himself was actually a non-autistic savant, born with brain abnormalities including a malformed cerebellum and an absent corpus callosum (the massive bundle of tissue that usually connects the two hemispheres). His savant skills were astonishing and included calendar calculation, as well as an encyclopaedic knowledge of history, literature, classical music, US zip codes and travel routes. It was estimated that he read more than 12,000 books in his life time, all of them committed to flawless memory. Although outgoing and sociable, Peek had coordination problems and struggled with abstract or conceptual thinking.

“Anna O.” is the pseudonym for Bertha Pappenheim, a pioneering German Jewish feminist and social worker who died in 1936 aged 77. As Anna O. she is known as one of the first ever patients to undergo psychoanalysis and her case inspired much of Freud’s thinking on mental illness. Pappenheim first came to the attention of another psychoanalyst, Joseph Breuer, in 1880 when he was called to her house in Vienna where she was lying in bed, almost entirely paralysed. Her other symptoms include hallucinations, personality changes and rambling speech, but doctors could find no physical cause. For 18 months, Breuer visited her almost daily and talked to her about her thoughts and feelings, including her grief for her father, and the more she talked, the more her symptoms seemed to fade – this was apparently one of the first ever instances of psychoanalysis or “the talking cure”, although the degree of Breuer’s success has been disputed and some historians allege that Pappenheim did have an organic illness, such as epilepsy. Although Freud never met Pappenheim, he wrote about her case, including the notion that she had a hysterical pregnancy, although this too is disputed. The latter part of Pappenheim’s life in Germany post 1888 is as remarkable as her time as Anna O. She became a prolific writer and social pioneer, including authoring stories, plays, and translating seminal texts, and she founded social clubs for Jewish women, worked in orphanages and founded the German Federation of Jewish Women.

Kitty Genovese

Sadly, it is not really Kitty Genovese the person who has become one of psychology’s classic case studies, but rather the terrible fate that befell her. In 1964 in New York, Genovese was returning home from her job as a bar maid when she was attacked and eventually murdered by Winston Mosely. What made this tragedy so influential to psychology was that it inspired research into what became known as the Bystander Phenomenon – the now well-established finding that our sense of individual responsibility is diluted by the presence of other people. According to folklore, 38 people watched Genovese’s demise yet not one of them did anything to help, apparently a terrible real life instance of the Bystander Effect. However, the story doesn’t end there because historians have since established  the reality was much more complicated  – at least two people did try to summon help, and actually there was only one witness the second and fatal attack. While the main principle of the Bystander Effect has stood the test of time, modern psychology’s understanding of the way it works has become a lot more nuanced. For example, there’s evidence that in some situations people are more likely to act when they’re part of a larger group, such as when they and the other group members all belong to the same social category (such as all being women) as the victim.

Little Albert

“Little Albert” was the nickname that the pioneering behaviourist psychologist John Watson gave to an 11-month-old baby, in whom, with his colleague and future wife Rosalind Rayner, he deliberately attempted to instill certain fears through a process of conditioning. The research, which was of dubious scientific quality, was conducted in 1920 and has become notorious for being so unethical (such a procedure would never be given approval in modern university settings). Interest in Little Albert has reignited in recent years as an academic quarrel has erupted over his true identity. A group led by Hall Beck at Appalachian University announced in 2011 that they thought Little Albert was actually Douglas Merritte, the son of a wet nurse at John Hopkins University where Watson and Rayner were based. According to this sad account, Little Albert was neurologically impaired, compounding the unethical nature of the Watson/Rayner research, and he died aged six of  hydrocephalus (fluid on the brain). However, this account was challenged by a different group of scholars led by Russell Powell at MacEwan University in 2014. They established that Little Albert was more likely William A Barger (recorded in his medical file as Albert Barger), the son of a different wet nurse. Earlier this year, textbook writer Richard Griggs weighed up all the evidence and concluded that the Barger story is the more credible, which would mean that Little Albert in fact died 2007 aged 87.

Chris Sizemore

Chris Costner Sizemore is one of the most famous patients to be given the controversial diagnosis of multiple personality disorder, known today as dissociative identity disorder. Sizemore’s alter egos apparently included Eve White, Eve Black, Jane and many others. By some accounts, Sizemore expressed these personalities as a coping mechanism in the face of traumas she experienced in childhood, including seeing her mother badly injured and a man sawn in half at a lumber mill. In recent years, Sizemore has described how her alter egos have been combined into one united personality for many decades, but she still sees different aspects of her past as belonging to her different personalities. For example, she has stated that her husband was married to Eve White (not her), and that Eve White is the mother of her first daughter. Her story was turned into a movie in 1957 called  The Three Faces of Eve  (based on a book of the same name written by her psychiatrists). Joanne Woodward won the best actress Oscar for portraying Sizemore and her various personalities in this film. Sizemore published her autobiography in 1977 called  I’m Eve . In 2009, she appeared on the BBC’s  Hard Talk  interview show.

David Reimer

One of the most famous patients in psychology, Reimer lost his penis in a botched circumcision operation when he was just 8 months old. His parents were subsequently advised by psychologist John Money to raise Reimer as a girl, “Brenda”, and for him to undergo further surgery and hormone treatment to assist his gender reassignment.

Money initially described the experiment (no one had tried anything like this before) as a huge success that appeared to support his belief in the important role of socialisation, rather than innate factors, in children’s gender identity. In fact, the reassignment was seriously problematic and Reimer’s boyishness was never far beneath the surface. When he was aged 14, Reimer was told the truth about his past and set about reversing the gender reassignment process to become male again. He later campaigned against other children with genital injuries being gender reassigned in the way that he had been. His story was turned into the book  As Nature Made Him, The Boy Who Was Raised As A Girl  by John Colapinto, and he is the subject of two BBC Horizon documentaries. Tragically, Reimer took his own life in 2004, aged just 38.

Christian Jarrett  ( @Psych_Writer ) is Editor of  BPS Research Digest

This article was originally published on  BPS Research Digest . Read the  original article .

This page has been archived and is no longer being updated regularly.

Lessons from H.M.

September 2005, Vol 36, No. 8

Print version: page 59

• Learning and Memory
• Psychotherapy

For more than 50 years, he's lived without major portions of his brain. Yet at 79, H.M., as he is known in the literature, continues to be a research dream-come-true.

"No one person seems to have contributed more to our understanding of human memory than H.M.," says Brian Sotko, a medical student at Harvard University who has been studying H.M.'s cognitive capabilities.

Because of radical 1953 surgery to stop intense and uncontrollable seizures, H.M. is the only patient alive today who has had a near-complete removal of the hippocampus, amygdala and surrounding cortex on both sides of his brain. After the surgery, the seizures were infrequent, but he lost his ability to remember new facts about people, places or things after a few seconds--a condition called anterograde amnesia.

Over the years, neuroscientists have learned via H.M. how these brain regions help form memories. And he's still helping. Skotko, who began his research while an undergraduate at Duke University, teamed up with Duke and Massachusetts Institute of Technology (MIT) neuroscientists to assess whether H.M. could learn more than was initially thought. The findings, published last November in the APA journal Neuropsychology (Vol. 18, No. 4, pages 756-769) were surprising to Skotko, who says it appears that, "H.M. was able to acquire new semantic information that we would not have expected for someone with profound anterograde amnesia."

Because H.M. does crossword puzzles daily, Skotko and his colleagues constructed crosswords with clues that relied on worldly knowledge H.M. acquired prior to his 1953 surgery and used them as anchors to which H.M. could learn from clues referring to events since 1953--for example, that John F. Kennedy became president and was assassinated (JFK was a well-known political figure prior to 1953).

H.M.'s crossword-puzzle performance revealed that he was able to learn new facts about well-known post-1953 people, places and events. "We suggest that H.M. might be using his residual posterior parahippocampal gyrus to support his learning," says Skotko.

The findings confirm those of more traditional cognitive tests conducted a few years earlier at MIT. After graduate students Gail O'Kane and Elizabeth Kensinger taught H.M. about people who became famous after his surgery, he recalled--given fact clues--23 out of 35 celebrity last names. In forced-choice recognition, H.M. not only differentiated 87 percent of the post-1953 famous names from names pulled from the phone book, but, remarkably, volunteered unique identifying facts for about a third, describing John Glenn as "the first rocketeer" and saying Julie Andrews was "famous for singing on Broadway."

"I've known H.M. since 1962, and he still doesn't know who I am," notes MIT neuroscientist Suzanne Corkin, PhD, a longtime H.M. researcher who directed the research. Nonetheless, she says, H.M. may have picked up the knowledge about famous people from watching television, reading the paper, doing puzzles and so on. The MIT report, published in 2004 in the journal Hippocampus (Vol. 14, No. 4, pages 417-425), concludes, "The results [provide] robust, unambiguous evidence that some new semantic learning can be supported by structures beyond the hippocampus proper." Corkin thinks H.M. may be tapping his intact perirhinal and parahippocampal structures, which may work as a team with some cortical areas as well.

H.M. seems to know that he is helping science. Says Skotko, "He has been known to say, 'What they learn about me will help them to help others.'"

--R. ADELSON

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Descriptive Research and Case Studies

Learning objectives.

• Explain the importance and uses of descriptive research, especially case studies, in studying abnormal behavior

Types of Research Methods

There are many research methods available to psychologists in their efforts to understand, describe, and explain behavior and the cognitive and biological processes that underlie it. Some methods rely on observational techniques. Other approaches involve interactions between the researcher and the individuals who are being studied—ranging from a series of simple questions; to extensive, in-depth interviews; to well-controlled experiments.

The three main categories of psychological research are descriptive, correlational, and experimental research. Research studies that do not test specific relationships between variables are called descriptive, or qualitative, studies . These studies are used to describe general or specific behaviors and attributes that are observed and measured. In the early stages of research, it might be difficult to form a hypothesis, especially when there is not any existing literature in the area. In these situations designing an experiment would be premature, as the question of interest is not yet clearly defined as a hypothesis. Often a researcher will begin with a non-experimental approach, such as a descriptive study, to gather more information about the topic before designing an experiment or correlational study to address a specific hypothesis. Descriptive research is distinct from correlational research , in which psychologists formally test whether a relationship exists between two or more variables. Experimental research goes a step further beyond descriptive and correlational research and randomly assigns people to different conditions, using hypothesis testing to make inferences about how these conditions affect behavior. It aims to determine if one variable directly impacts and causes another. Correlational and experimental research both typically use hypothesis testing, whereas descriptive research does not.

Each of these research methods has unique strengths and weaknesses, and each method may only be appropriate for certain types of research questions. For example, studies that rely primarily on observation produce incredible amounts of information, but the ability to apply this information to the larger population is somewhat limited because of small sample sizes. Survey research, on the other hand, allows researchers to easily collect data from relatively large samples. While surveys allow results to be generalized to the larger population more easily, the information that can be collected on any given survey is somewhat limited and subject to problems associated with any type of self-reported data. Some researchers conduct archival research by using existing records. While existing records can be a fairly inexpensive way to collect data that can provide insight into a number of research questions, researchers using this approach have no control on how or what kind of data was collected.

Correlational research can find a relationship between two variables, but the only way a researcher can claim that the relationship between the variables is cause and effect is to perform an experiment. In experimental research, which will be discussed later, there is a tremendous amount of control over variables of interest. While performing an experiment is a powerful approach, experiments are often conducted in very artificial settings, which calls into question the validity of experimental findings with regard to how they would apply in real-world settings. In addition, many of the questions that psychologists would like to answer cannot be pursued through experimental research because of ethical concerns.

The three main types of descriptive studies are case studies, naturalistic observation, and surveys.

Clinical or Case Studies

Psychologists can use a detailed description of one person or a small group based on careful observation.  Case studies  are intensive studies of individuals and have commonly been seen as a fruitful way to come up with hypotheses and generate theories. Case studies add descriptive richness. Case studies are also useful for formulating concepts, which are an important aspect of theory construction. Through fine-grained knowledge and description, case studies can fully specify the causal mechanisms in a way that may be harder in a large study.

Sigmund Freud   developed  many theories from case studies (Anna O., Little Hans, Wolf Man, Dora, etc.). F or example, he conducted a case study of a man, nicknamed “Rat Man,”  in which he claimed that this patient had been cured by psychoanalysis.  T he nickname derives from the fact that among the patient’s many compulsions, he had an obsession with nightmarish fantasies about rats. 

Today, more commonly, case studies reflect an up-close, in-depth, and detailed examination of an individual’s course of treatment. Case studies typically include a complete history of the subject’s background and response to treatment. From the particular client’s experience in therapy, the therapist’s goal is to provide information that may help other therapists who treat similar clients.

Case studies are generally a single-case design, but can also be a multiple-case design, where replication instead of sampling is the criterion for inclusion. Like other research methodologies within psychology, the case study must produce valid and reliable results in order to be useful for the development of future research. Distinct advantages and disadvantages are associated with the case study in psychology.

A commonly described limit of case studies is that they do not lend themselves to generalizability . The other issue is that the case study is subject to the bias of the researcher in terms of how the case is written, and that cases are chosen because they are consistent with the researcher’s preconceived notions, resulting in biased research. Another common problem in case study research is that of reconciling conflicting interpretations of the same case history.

Despite these limitations, there are advantages to using case studies. One major advantage of the case study in psychology is the potential for the development of novel hypotheses of the  cause of abnormal behavior   for later testing. Second, the case study can provide detailed descriptions of specific and rare cases and help us study unusual conditions that occur too infrequently to study with large sample sizes. The major disadvantage is that case studies cannot be used to determine causation, as is the case in experimental research, where the factors or variables hypothesized to play a causal role are manipulated or controlled by the researcher. 

Link to Learning: Famous Case Studies

Some well-known case studies that related to abnormal psychology include the following:

• Harlow— Phineas Gage
• Breuer & Freud (1895)— Anna O.
• Cleckley’s case studies: on psychopathy ( The Mask of Sanity ) (1941) and multiple personality disorder ( The Three Faces of Eve ) (1957)
• Freud and  Little Hans
• Freud and the  Rat Man
• John Money and the  John/Joan case
• Genie (feral child)
• Piaget’s studies
• Rosenthal’s book on the  murder of Kitty Genovese
• Washoe (sign language)
• Patient H.M.

Naturalistic Observation

If you want to understand how behavior occurs, one of the best ways to gain information is to simply observe the behavior in its natural context. However, people might change their behavior in unexpected ways if they know they are being observed. How do researchers obtain accurate information when people tend to hide their natural behavior? As an example, imagine that your professor asks everyone in your class to raise their hand if they always wash their hands after using the restroom. Chances are that almost everyone in the classroom will raise their hand, but do you think hand washing after every trip to the restroom is really that universal?

This is very similar to the phenomenon mentioned earlier in this module: many individuals do not feel comfortable answering a question honestly. But if we are committed to finding out the facts about handwashing, we have other options available to us.

Suppose we send a researcher to a school playground to observe how aggressive or socially anxious children interact with peers. Will our observer blend into the playground environment by wearing a white lab coat, sitting with a clipboard, and staring at the swings? We want our researcher to be inconspicuous and unobtrusively positioned—perhaps pretending to be a school monitor while secretly recording the relevant information. This type of observational study is called naturalistic observation : observing behavior in its natural setting. To better understand peer exclusion, Suzanne Fanger collaborated with colleagues at the University of Texas to observe the behavior of preschool children on a playground. How did the observers remain inconspicuous over the duration of the study? They equipped a few of the children with wireless microphones (which the children quickly forgot about) and observed while taking notes from a distance. Also, the children in that particular preschool (a “laboratory preschool”) were accustomed to having observers on the playground (Fanger, Frankel, & Hazen, 2012).

It is critical that the observer be as unobtrusive and as inconspicuous as possible: when people know they are being watched, they are less likely to behave naturally. For example, psychologists have spent weeks observing the behavior of homeless people on the streets, in train stations, and bus terminals. They try to ensure that their naturalistic observations are unobtrusive, so as to minimize interference with the behavior they observe. Nevertheless, the presence of the observer may distort the behavior that is observed, and this must be taken into consideration (Figure 1).

The greatest benefit of naturalistic observation is the validity, or accuracy, of information collected unobtrusively in a natural setting. Having individuals behave as they normally would in a given situation means that we have a higher degree of ecological validity, or realism, than we might achieve with other research approaches. Therefore, our ability to generalize the findings of the research to real-world situations is enhanced. If done correctly, we need not worry about people modifying their behavior simply because they are being observed. Sometimes, people may assume that reality programs give us a glimpse into authentic human behavior. However, the principle of inconspicuous observation is violated as reality stars are followed by camera crews and are interviewed on camera for personal confessionals. Given that environment, we must doubt how natural and realistic their behaviors are.

The major downside of naturalistic observation is that they are often difficult to set up and control. Although something as simple as observation may seem like it would be a part of all research methods, participant observation is a distinct methodology that involves the researcher embedding themselves into a group in order to study its dynamics. For example, Festinger, Riecken, and Shacter (1956) were very interested in the psychology of a particular cult. However, this cult was very secretive and wouldn’t grant interviews to outside members. So, in order to study these people, Festinger and his colleagues pretended to be cult members, allowing them access to the behavior and psychology of the cult. Despite this example, it should be noted that the people being observed in a participant observation study usually know that the researcher is there to study them. [1]

Another potential problem in observational research is observer bias . Generally, people who act as observers are closely involved in the research project and may unconsciously skew their observations to fit their research goals or expectations. To protect against this type of bias, researchers should have clear criteria established for the types of behaviors recorded and how those behaviors should be classified. In addition, researchers often compare observations of the same event by multiple observers, in order to test inter-rater reliability : a measure of reliability that assesses the consistency of observations by different observers.

Often, psychologists develop surveys as a means of gathering data. Surveys are lists of questions to be answered by research participants, and can be delivered as paper-and-pencil questionnaires, administered electronically, or conducted verbally (Figure 3). Generally, the survey itself can be completed in a short time, and the ease of administering a survey makes it easy to collect data from a large number of people.

Surveys allow researchers to gather data from larger samples than may be afforded by other research methods . A sample is a subset of individuals selected from a population , which is the overall group of individuals that the researchers are interested in. Researchers study the sample and seek to generalize their findings to the population.

There is both strength and weakness in surveys when compared to case studies. By using surveys, we can collect information from a larger sample of people. A larger sample is better able to reflect the actual diversity of the population, thus allowing better generalizability. Therefore, if our sample is sufficiently large and diverse, we can assume that the data we collect from the survey can be generalized to the larger population with more certainty than the information collected through a case study. However, given the greater number of people involved, we are not able to collect the same depth of information on each person that would be collected in a case study.

Another potential weakness of surveys is something we touched on earlier in this module: people do not always give accurate responses. They may lie, misremember, or answer questions in a way that they think makes them look good. For example, people may report drinking less alcohol than is actually the case.

Any number of research questions can be answered through the use of surveys. One real-world example is the research conducted by Jenkins, Ruppel, Kizer, Yehl, and Griffin (2012) about the backlash against the U.S. Arab-American community following the terrorist attacks of September 11, 2001. Jenkins and colleagues wanted to determine to what extent these negative attitudes toward Arab-Americans still existed nearly a decade after the attacks occurred. In one study, 140 research participants filled out a survey with 10 questions, including questions asking directly about the participant’s overt prejudicial attitudes toward people of various ethnicities. The survey also asked indirect questions about how likely the participant would be to interact with a person of a given ethnicity in a variety of settings (such as, “How likely do you think it is that you would introduce yourself to a person of Arab-American descent?”). The results of the research suggested that participants were unwilling to report prejudicial attitudes toward any ethnic group. However, there were significant differences between their pattern of responses to questions about social interaction with Arab-Americans compared to other ethnic groups: they indicated less willingness for social interaction with Arab-Americans compared to the other ethnic groups. This suggested that the participants harbored subtle forms of prejudice against Arab-Americans, despite their assertions that this was not the case (Jenkins et al., 2012).

Think it Over

Research has shown that parental depressive symptoms are linked to a number of negative child outcomes. A classmate of yours is interested in  the associations between parental depressive symptoms and actual child behaviors in everyday life [2] because this associations remains largely unknown. After reading this section, what do you think is the best way to better understand such associations? Which method might result in the most valid data?

clinical or case study:  observational research study focusing on one or a few people

correlational research:  tests whether a relationship exists between two or more variables

descriptive research:  research studies that do not test specific relationships between variables; they are used to describe general or specific behaviors and attributes that are observed and measured

experimental research:  tests a hypothesis to determine cause-and-effect relationships

generalizability:  inferring that the results for a sample apply to the larger population

inter-rater reliability:  measure of agreement among observers on how they record and classify a particular event

naturalistic observation:  observation of behavior in its natural setting

observer bias:  when observations may be skewed to align with observer expectations

population:  overall group of individuals that the researchers are interested in

sample:  subset of individuals selected from the larger population

survey:  list of questions to be answered by research participants—given as paper-and-pencil questionnaires, administered electronically, or conducted verbally—allowing researchers to collect data from a large number of people

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• Research Designs.  Authored by : Christie Napa Scollon.  Provided by : Singapore Management University.  Located at :  https://nobaproject.com/modules/research-designs#reference-6 .  Project : The Noba Project.  License :  CC BY-NC-SA: Attribution-NonCommercial-ShareAlike
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• Scollon, C. N. (2020). Research designs. In R. Biswas-Diener & E. Diener (Eds), Noba textbook series: Psychology. Champaign, IL: DEF publishers. Retrieved from http://noba.to/acxb2thy ↵
• Slatcher, R. B., & Trentacosta, C. J. (2011). A naturalistic observation study of the links between parental depressive symptoms and preschoolers' behaviors in everyday life. Journal of family psychology : JFP : journal of the Division of Family Psychology of the American Psychological Association (Division 43), 25(3), 444–448. https://doi.org/10.1037/a0023728 ↵

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