Lecture 2- Learning and Memory I

Question 1

What are the disorders involving deficits in learning and memory?

Answer 1

-autism, attention deficit disorder, down syndrome -depression, schizophrenia, addiction -alzheimer’s disease, dementia, Huntington’s disease

Question 2

What did the patient experience when a) the somatosensory b) associated motor and c) auditory cortex were stimulated during a neurosurgery?

Answer 2

a) tingling in the left thumb b) protrusion of the tongue c) hears specific orchestral music

Question 3

What area of the brain is responsible for face recognition?

Answer 3

-fusiform face area

Question 4

What happened to patient H.M.?

Answer 4

-severe anterograde amnesia -bilateral resection of medial structures of the temporal lobe to treat severe epilepsy -profound impairment of recent memory in absence of other intellectual loss (IQ 112 post-surgery) -could not remember what he had for breakfast, find his way around a hospital or recognise anyone he had met since the surgery -MRI reveals medial temporal lobe lesion

Question 5

Why couldn’t H.M. remember anything new?

Answer 5

-able to hold immediate impressions in his mind but as soon as his attention was diverted they were lost -could remember childhood -the transport from short term to long term memory no longer active due to absence of the hippocampi

Question 6

What is the story with H.M. and the star test?

Answer 6

-proved unconscious (procedural) memory -did the test and improved over time despite not being able to recollect doing the task before

Question 7

How do we classify memory?

Answer 7

1. declarative (explicit): facts and events, hippocampus, medial temporal lobe;diencephalon
2. nondeclarative (implicit)
   a) skills and habits= striatum, motor cortex, cerebellum
   b) priming= neocortex
   c) basic associative learning i) emotional responses= amygdala ii) skeletal musculature= cerebellum
   d) nonassociative learning= reflex pathways

Question 8

What were the experimental results concerning the London cab drivers?

Answer 8

-structural MRI showed enlarged posterior hippocampi in London cabbies compared to non drivers -evidence that changes in hippocampal grey matter are acquired with experience

Question 9

What are the three NMDA receptor subtypes?

Answer 9

1. NR1
2. NR2A
3. NR2B

Question 10

What happened to the mice that had the NMDA gene inactivated?

Answer 10

-control= inbred, don’t differ much genetically -mutant= inactivated gene for something, the NMDA receptor protein removed from hippocampus -wild= normal when platform dropped, wild knows it should be there, mutant doesn’t, no memory of it

Question 11

What does the hippocampus do?

Answer 11

-stores memories and converts them from short to long term memories

Question 12

What does recording neuron activity show?

Answer 12

• short term changes= fast
• long term changes= slow

Question 13

PIC4How does NMDA change from childhood to adulthood?

Answer 13

-shift to N2RA subunit after development -at first increased N2RB when increased capacity for learning then shifts to N2RA

Question 14

What happens in mice where the young version of NMDA is maintained (N2RB)?

Answer 14

-smart mice -the increased ability for learning remains

Question 15

How is synaptic strength affected in mutant mice with NR2B?

Answer 15

-when NR2B then strong synaptic connection= more extended developmental form of learning

Question 16

Is the young brain more plastic?

Answer 16

-yes -grey matter decreases throughout life -not fully developed until mid twenties

Question 17

Where are memories stored?

Answer 17

-medial temporal lobe: hippocampus

Question 18

What is involved in short term memory storage?

Answer 18

-insertion of AMPA receptors, phosphorylation, enhanced presynaptic release via retrograde signalling (short-term memory)

Question 19

What is involved in long-term memory storage?

Answer 19

-protein synthesis, structural changes (long-term memory)

Question 20

What happens in the brain during exercise?

Answer 20

-release of growth factors (e.g. BNDF) and generation of new neurons -improvements in mood and memory -increased blood flow to brain -elevated mood -increased birth of new neurons? improves learning and memory?

Question 21

How does early physical exercise affect stroke outcomes?

Answer 21

-improves it -very early rehabilitation (less than 24 hours) with an emphasis on mobilisation may contribute to improved outcomes following stroke -50% of patients who exercise early are back on their feet within 3 days

Question 22

How does the surrounding environment affect brain function?

Answer 22

-environment changes brain function -mental stimulation and physical activity delays huntington’s alzheimers -more complex environment helps

Question 23

How do you translate theories developed on mice into treatments for humans?

Answer 23

genetic studies= use genetically modified mice= test novel therapies (environmental, new drugs)= clinical trials