Learning and Memory

Question 1

H. M.

amnesia

Answer 1

H.M. had bilateral medial temporal lobectomy due to severe epilepsy.

1. removal of the medial portions of both temporal lobes
2. removal of much of the amygdala and hippocampus.
   
   1. short-term and remote long-term memory were intact.
   2. unable to form new long-term memories (anterograde) and trouble remembering events that occured a few years prior to the surgery (retrograde amnesia for recent events).
   3. explicit and declarative impacted not implicit and procedural memories.
3. Left Cerebral Cortex: active during the encoding of memories
4. Right Cerebral Cortex: active during retrieval (esp right frontal cortex).
   
   1. this phenomenon is called hemispheric encoding/retrival asymmetry or HERA.

Question 2

Brain Mechanisms of

Memory and Learning

Temporal Lobes

Hippocampus

Amygdala

Prefrontal Cortex

Thalamus

Basal Ganglia, Cerebellum and Motor Cortex

Answer 2

1. Temporal Lobes: encoding, storage, and retrival of long-term declarative memories.
   
   1. Right TL: nonverbal memory tasks impaired
      
      1. (face-recognition, spatial postioning, maze learning and emotional learning)
   2. Left TL: impaired performance on measures of verbal memory (recall of word lists and stories and recognition of words and numbers).

Question 3

2. Hippocampus

Answer 3

1. Hippocampus: consolidates long-term declarative memories (transferring info from short-term to long term memory, but not the storage.
2. essential for spatial memories
3. Explicit memory: memeory requiring conscious recollection
4. degeneration of the neurons in the hippocampus linked to normal aging memory loss and Alzheimer’s dementia.
5. Alzheimer’s: amyloid plaques in the hippocampus, amygdala and entorhinal cortex and mutation of the ApoE gene contributes to the build-up of plaques.
6. Chronic stress due to depression, poverty, and other factors may impair memory due to effects of cortisol and other stress hormones on the hippocampus.

Question 4

3. Amygdala

Answer 4

1. fear conditioning and adding emotional significance to memories.
2. recall of tramatic events and contributes to PTSD

Question 5

4. Prefrontal Cortex

Answer 5

1. Episodic memory and prospective memory
2. constructive memory and false recognition.
3. injuries to prefontal cortex: people may incorrectly claim that new information is familiar.
4. Dorsolateral prefrontal cortex: working memory and impairments in working memory in patients with Schizophrenia have abnormal activity in this area.

Question 6

5. Thalamus

Answer 6

1. Thalamus: processing incoming information and transferring it to the cortex.
2. damage: anterograde amnesia, retrograde amnesia and confabulations (Korsakoff’s Syndrome).

Question 7

6. Basal Ganglia, Cerebellum and Motor Cortex

Answer 7

1. procedural memory (memory for snsorimotor skills)
2. implicit memory (unconscious, nonintentional)