Lecture 9: Learning and Memory 1 Flashcards
Who was patient H.M., and why did he undergo brain surgery?
H.M. (Henry Molaison) was a patient with severe epilepsy who underwent a bilateral medial temporal lobotomy to treat his condition.
What was the purpose of the medial temporal lobotomy in H.M.’s case?
The surgery aimed to alleviate his epilepsy, but it was an invasive and imprecise procedure.
What cognitive impairment did H.M. experience after his surgery?
He developed anterograde amnesia, meaning he was unable to form new memories after the surgery.
Who was the main researcher studying H.M.s condition?
Brenda Milner, a British-Canadian neuropsychologist, was the first to document the cognitive damage from the surgery.
How many other patients underwent similar surgeries to H.M.?
Eight other patients also had the surgery
Why is H.M.’s case considered ethically questionable?
The surgery was performed with limited knowledge of its risks and benefits, making its ethical acceptability debatable.
What was William Beecher Scoville’s attitude toward the surgery?
Scoville, the surgeon, prioritized action over thought and may have been motivated by career advancement rather than just therapeutic outcomes.
How did H.M.’s case impact medical practices regarding epilepsy surgery?
It highlighted the severe cognitive consequences of such surgeries, leading to a shift toward less invasive and more precise methods.
What brain structures were affected by H.M.’s surgery?
The surgery damaged the hippocampus (the intended target), amygdala, entorhinal cortex, and fully removed the parahippocampal cortex.
Why is it difficult to attribute H.M.’s memory impairments to a single brain region?
Multiple brain structures were damaged, making it impossible to determine which specific area was responsible for the memory deficits.
What was the broader impact of H.M.’s case on neuroscience?
It was a crucial starting point for human cognitive neuroscience, helping researchers link brain damage to cognitive functions.
What is the mirror tracing task, and why is it difficult?
The mirror tracing task requires tracing an image while viewing it in a mirror, making movements reversed and contradicting previous hand-eye coordination learning.
What type of learning does the mirror tracing task measure?
It measures motor skill learning but also requires unlearning previous motor habits, making it not “process pure.”
How is learning measured in the mirror tracing task?
Learning is measured by counting the number of tracing errors, which decrease over multiple training days.
What does the error rate on day 3 of the mirror tracing task indicate?
It reflects the cumulative learning from day 1 and day 2, showing that learning is retained over multiple days.
How did H.M. perform on the mirror tracing task?
He showed a normal motor learning curve, meaning he improved with practice despite his brain lesions.
Why was H.M.’s ability to learn the mirror tracing task surprising?
His brain lesions suggested that learning should be impaired, but his ability to improve indicated that motor learning occurs outside the damaged regions.
Could H.M. consciously remember doing the mirror tracing task before?
No, if asked, he would say he had never done the task before, despite showing improvement.
What type of memory was impaired in H.M.?
His declarative memory (which stores names, dates, facts, and events) was impaired.
What is a single dissociation in cognitive neuroscience?
It occurs when a person can do one cognitive task but not another, like H.M. who could learn a motor task but not remember doing it.
What is a double dissociation?
It occurs when another person with different brain damage shows the opposite pattern—struggling with motor learning but retaining declarative memory.
What conclusion was initially drawn about the hippocampus from H.M.’s case?
Researchers claimed that the hippocampus was crucial for declarative memory but not skill learning.
Why was the claim about the hippocampus overstated?
H.M.’s lesions were extensive, making it unclear whether declarative memory relies solely on the hippocampus or a broader network of brain regions.
What did later research reveal about learning and brain areas?
Learning requires a wide network of brain regions, rather than being confined to the hippocampus alone.