What part of the brain does Michael Jackson's brain surgery remove?
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.
How did Dr Scoville treat Molaison’s seizures?
Dr. Scoville ended up removing most of the anterior temporal lobe which included the hippocampus, the brain’s memory center, from both sides of Molaison’s brain. The procedure that Dr. Scoville called a “frankly experimental operation” worked – the seizures all but stopped.
What is brain resection surgery for epilepsy?
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, use of lasers and detailed brain scans help ensure valuable brain regions are not impacted.
Could this strategy help surgeons select specific brain areas to stop seizures?
The strategy, devised by Marinho Lopes of the University of Exeter and colleagues, could help surgeons select specific brain areas for removal to stop seizures. Epilepsy is a neurological disorder that affects about 1 out of every 100 people worldwide.
What part of the brain did H.M. remove?
At age 27, H.M., whose real name was Henry Molaison, underwent an experimental surgical treatment for his debilitating epilepsy. His surgeon removed the medial temporal lobe, including a structure called the hippocampus. Thereafter, H.M. was unable to form new memories.
What area of the brain did H.M. have removed during surgery to minimize his seizure disorder?
H.M., Henry Molaison, was one of the world's most famous amnesic patients. His amnesia was caused by an experimental brain operation, bilateral medial temporal lobe resection, carried out in 1953 to relieve intractable epilepsy.
How was H.M. treated?
H.M. was treated until 1984 with high dosages of phenytoin, which was the most prescribed anticonvulsant in the US, when anti-epileptic treatment was undertaken in H.M., and later on by carbamazepine.
What happened to H.M. when his hippocampus was removed?
When Henry Molaison (now widely known as H.M.) cracked his skull in an accident, he began blacking out and having seizures. In an attempt to cure him, daredevil surgeon Dr. William Skoville removed H.M.'s hippocampus. Luckily, the seizures did go away — but so did his long-term memory!
Why did H.M. have his hippocampus removed?
In an attempt to control his seizures, H. M. underwent brain surgery to remove his hippocampus and amygdala. 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.
What part of the brain was likely damaged in the case study of H.M. quizlet?
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.
When did Henry Molaison get his hippocampus removed?
September 1, 1953On September 1, 1953, Scoville removed Molaison's medial temporal lobes on both hemispheres including the hippocampi and most of the amygdalae and entorhinal cortex, the major sensory input to the hippocampi.
What does the hippocampus do?
Hippocampus is a complex brain structure embedded deep into temporal lobe. It has a major role in learning and memory. It is a plastic and vulnerable structure that gets damaged by a variety of stimuli. Studies have shown that it also gets affected in a variety of neurological and psychiatric disorders.
What is medial temporal lobe?
The medial temporal lobe (MTL) includes the hippocampus, amygdala and parahippocampal regions, and is crucial for episodic and spatial memory. MTL memory function consists of distinct processes such as encoding, consolidation and retrieval.
What is amygdala and hippocampus?
The amygdala is specialized for input and processing of emotion, while the hippocampus is essential for declarative or episodic memory. During emotional reactions, these two brain regions interact to translate the emotion into particular outcomes.
What happened to H.M. as a result of his surgery?
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.
Why did H.M. have surgery quizlet?
-HM had an accident as a child and sustained a serious head injury. -He had surgery after the bike accident where the tissue from the medial temporal lobe (including the hippocampus) was removed on both sides of HM´s brain.
Who was the most studied patient in the history of brain science?
Henry Gustav Molaison —known through most of his life only as H.M., to protect his privacy—became the most studied patient in the history of brain science after 1953, when an experimental brain operation left him, at age 27, unable to form new declarative memories. ...
Which lobes did Scoville remove?
On September 1, 1953, Scoville removed Molaison's medial temporal lobes on both hemispheres including the hippocampus and most of the amygdala and entorhinal cortex, the major sensory input to the hippocampus.
What is Molaison's contribution to memory?
Another contribution of Molaison to understanding of human memory regards the neural structures of the memory consolidation process , which is responsible for forming stable long-term memories (Eysenck & Keane, 2005). Molaison displayed a temporally graded retrograde amnesia in the way that he "could still recall childhood memories, but he had difficulty remembering events that happened during the years immediately preceding the surgery". His old memories were not impaired, whereas the ones relatively close to the surgery were. This is evidence that the older childhood memories do not rely on the medial temporal lobe, whereas the more recent long-term memories seem to do so ). The medial temporal structures, which were removed in the surgery, are hypothesized to be involved in the consolidation of memories in the way that "interactions between the medial temporal lobe and various lateral cortical regions are thought to store memories outside the medial temporal lobes by slowly forming direct links between the cortical representations of the experience".
What is Molaison's condition?
Molaison's general condition has been described as heavy anterograde amnesia, as well as temporally graded retrograde amnesia. Since Molaison did not show any memory impairment before the surgery, the removal of the medial temporal lobes can be held responsible for his memory disorder.
What was Molaison's job?
In 1953, Molaison was referred to William Beecher Scoville, a neurosurgeon at Hartford Hospital.
What happened to Henry Molaison?
Henry Molaison was born on February 26, 1926 in Manchester, Connecticut, and experienced intractable epilepsy that has sometimes been attributed to a bicycle accident at the age of seven. He had minor or partial seizures for many years, and then major or tonic-clonic seizures following his 16th birthday.
How many brain slices did Annese have?
On December 4, 2009, Annese's group acquired 2401 brain slices, with only two damaged slices and 16 potentially problematic slices. The digital 3D reconstruction of his brain was finished at the beginning of 2014. The results of the study were published in Nature Communications for January 2014.
What was H.M. the most studied individual in the history of neuroscience?
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.
Why is H.M. memory impairment so severe?
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.
What did Scoville tell Penfield?
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.
Why do remote memories fade?
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.
How old was H.M. when he was knocked down by a bicycle?
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.)
Which structure is most important for memory?
The structures with special importance for these kinds of memory include the basal ganglia, the cerebellum, the amygdala, and the neocortex.
Is memory impaired in H.M.?
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.
What part of the brain is removed from H.M.?
That’s because H.M.’s surgery removed not only parts of the hippocampus, but the entire ‘entorhinal cortex, ’ a region that connects the hippocampus to the cortex, or outer layers of the brain. In animal models, Witter says, “removal of entorhinal inputs generally lead to striking changes” in the hippocampus.
Who was the neuropathologist who extracted H.M.'s brain?
After landing, and pounding a few cups of coffee, he went to the hospital to join neuropathologist Matthew Frosch in the meticulous and high-stakes extraction of H.M.’s brain. H.M. had one of the most important brains in the world, at least if you ask a neuroscientist. In 1953, at age 27, he underwent experimental brain surgery to treat ...
Where did Annese take his brain?
Then Annese took it to California, to his lab at The Brain Observatory at the University of California, San Diego. Over the next 10 months, Annese gradually added sucrose to the buffer, creating a cryoprotectant that would allow the entire brain to be frozen without forming tissue-damaging ice crystals.
How long did the cadaver stay in the MRI machine?
The cadaver spent the next nine hours inside of an MRI machine, getting scanned every which way. Meanwhile, on the other side of the country, neuroanatomist Jacopo Annese rushed to the San Diego airport and boarded a red-eye flight to Boston. After landing, and pounding a few cups of coffee, he went to the hospital to join neuropathologist Matthew ...
How long did Henry Molaison stay in the hospital?
Not long after, the body of 82-year-old Henry Molaison — known simply as H.M. in hundreds of scientific papers — went on a two-hour ride from his nursing home in Windsor Locks, Connecticut, to Massachusetts General Hospital in Boston. The cadaver spent the next nine hours inside of an MRI machine, getting scanned every which way.
What did H.M. learn from his surgery?
Though he couldn’t remember what he had for breakfast, H.M. could learn new motor memory tasks and had normal intelligence, illustrating both the specificity of the hippocampus and the multifaceted nature of memory.
How many brains are in Annese's freezing and cutting procedure?
H.M.’s brain is the most famous of about 60 brains that are currently undergoing Annese’s new freezing-and-cutting procedure, and 300 living people have signed up to donate theirs.
Overview
Henry Gustav Molaison (February 26, 1926 – December 2, 2008), known widely as H.M., was an American who had a bilateral medial temporal lobectomy to surgically resect the anterior two thirds of his hippocampi, parahippocampal cortices, entorhinal cortices, piriform cortices, and amygdalae in an attempt to cure his epilepsy. Although the surgery was partially successful in controlling h…
Biography
Henry Molaison was born on February 26, 1926, in Manchester, Connecticut, and experienced intractable epilepsy that has sometimes been attributed to a bicycle accident at the age of seven. He had minor or partial seizures for many years, and then major or tonic-clonic seizures following his 16th birthday. He worked for a time on an assembly line but, by the age of 27, he had become so incapacitated by his seizures, despite high doses of anticonvulsant medication, that he could …
Insights into memory formation
Molaison was influential not only for the knowledge he provided about memory impairment and amnesia, but also because it was thought his exact brain surgery allowed a good understanding of how particular areas of the brain may be linked to specific processes hypothesized to occur in memory formation. In this way, his case was taken to provide information about brain pathology, and helped to form theories of normal memory function.
Contribution to science
The study of Molaison revolutionized the understanding of the organization of human memory. It has provided broad evidence for the rejection of old theories and the formation of new theories on human memory, in particular about its processes and the underlying neural structures (cf. Kolb & Whishaw, 1996). In the following, some of the major insights are outlined.
Molaison's brain was the subject of an anatomical study funded by the Dana Foundation and the National …
Post-death controversy
On August 7, 2016, a New York Times article written by Luke Dittrich, grandson of Molaison's neurosurgeon William Beecher Scoville, raised a number of concerns about how Molaison's data and consent process had been conducted by the primary scientist investigating him, Suzanne Corkin. The article suggested that Corkin had destroyed research documents and data, and failed to obtain consent from Molaison's closest living kin. In response to the article, a group of over 2…
See also
• Cognitive neuropsychology
• Kent Cochrane, a similar patient who lost episodic memory after a motorcycle crash
• Clive Wearing, whose amnesia appeared after an infection
• Phineas Gage, a 19th-century railroad worker who survived an accident where a metal rod went through his brain
Notes
1. ^ The bicycle accident was initially reported to have occurred at age nine. This was subsequently corrected to age seven, to accord with clarification from H.M.'s mother.
Further reading
• S. Corkin (2002). "What's new with the amnesic patient H.M.?" (PDF). Nature Reviews Neuroscience. 3 (2): 153–160. doi:10.1038/nrn726. PMID 11836523. S2CID 5429133. Archived from the original (PDF) on September 12, 2004.
• H. Schmolck; E.A. Kensinger; S. Corkin; L. Squire (2002). "Semantic knowledge in Patient H.M. and other patients with bilateral medial and lateral temporal lobe lesions" (PDF). Hippocampus. 12 (4): 520–533. doi:10.1002/hipo.10039. PMID
• S. Corkin (2002). "What's new with the amnesic patient H.M.?" (PDF). Nature Reviews Neuroscience. 3 (2): 153–160. doi:10.1038/nrn726. PMID 11836523. S2CID 5429133. Archived from the original (PDF) on September 12, 2004.
• H. Schmolck; E.A. Kensinger; S. Corkin; L. Squire (2002). "Semantic knowledge in Patient H.M. and other patients with bilateral medial and lateral temporal lobe lesions" (PDF). Hippocampus. 12 (4): 520–533. doi:10.1002/hipo.10039. PMID 12201637. S2…