week 7: memory 2

Question 1

The multiple-trace hypothesis of memory classifies memory by duration:

Answer 1

Iconic memories are the briefest.
Short-term memories (STMs) are longer.
The most enduring form of memory is long-term memories (LTMs) which can last for days or years.

Question 2

LTM categories

Answer 2

declarative

non-declarative (procedural)

Question 3

what is Nondeclarative (procedural) memory

Answer 3

Things you know that you can show by doing (e.g., grammar, or motor skills, or problem-solving)
-unconscious memory (implicit)

Question 4

what is Declarative memory

Answer 4

Things you know that you can tell others (e.g., facts and events)
-explicit memory (conscious memory)

Question 5

Two subtypes of declarative memory

Answer 5

Semantic memory – generalised memory

Episodic memory – autobiographical

Question 6

nondeclarative (procedurall) subcategories

Answer 6

skill learning (eg, bike riding)
priming (eg, being more likely to use a new word)
conditioning (eg, salivating when you see food)

Question 7

Brain structures involved in learning and memory

Answer 7

central temporal lobes

Question 8

Henry Gustav Molaison (H.M.)

Answer 8

suffered seizures

eeg showed abnormalities in central temporal lobes

Question 9

Henry Gustav Molaison (H.M.) surgery

Answer 9

bilateral medial temporal lobectomy
removal of the medial portions of both temporal lobes including most of the hippocampus, amygdala and adjacent cortex (rhinal cortex).

Question 10

HM results

Answer 10

Preserved perceptual and motor abilities
Preserved STM
Some retrograde amnesia
Severe anterograde amnesia

Question 11

Anterograde amnesia

Answer 11

loss of memory after injury event

Question 12

Retrograde amnesia

Answer 12

loss of memory prior to injury event

Question 13

what formal assessments were conducted for HMs amnesia

Answer 13

Digit span + 1 test
Block tapping memory span test
Mirror drawing test
Incomplete pictures test

Question 14

HM Digit span + 1 test results

Answer 14

Showed HM’s inability to form new long term memories for verbal information

Question 15

Block tapping memory span test

HM results

Answer 15

Showed that his inability to form new memories was not just restricted to verbal information

Question 16

Mirror drawing test

HM results

Answer 16

Despite not remembering the test, HM’s performance improved

Question 17

Incomplete pictures test

HM results

Answer 17

Despite not remembering the test, HM’s performance improved

Question 18

Incomplete pictures test

HM results

Answer 18

Despite not remembering the test, HM’s performance improved

Question 19

Why was it so difficult to create an animal model of HM’s amnesia?

Answer 19

1. wasn’t initially apparent that HM’s anterograde amnesia was specific to declarative (explicit) long term memories.
2. incorrectly assumed that the amnesic effects of medial temporal lobe damage were largely attributable to hippocampal damage. Thus most efforts to develop animal models focussed on hippocampal lesions.

Question 20

The delayed non-matching-to-sample task.

Answer 20

method for testing declarative memory in monkeys

Question 21

what did The delayed non-matching-to-sample task provide

Answer 21

provided a means of testing the assumption that the amnesia resulting from medial temporal lobe damage is entirely the consequence of hippocampal damage

Question 22

what does Bilateral surgical removal of the perirhinal cortex produce

Answer 22

produces severe and permanent deficits in performance on the delayed non-matching-to-sample test and other tests of object recognition

Question 23

bilateral surgical removal of the hippocampus produces?

Answer 23

either moderate deficits or none at al

Question 24

Bilateral destruction of the amygdala produces?

Answer 24

no effect on object recognition

Question 25

Synaptic mechanisms of learning and memory trends

Answer 25

Structural changes at synapses

Physiological changes at synapses

Question 26

Structural changes at synapses may include

Answer 26

Formation of new synapses
Rearrangement of synapses
Neurogenesis

Question 27

Physiological changes at synapses may include

Answer 27

Long-term potentiation (LTP) (a stable and enduring increase in the effectiveness of synapses)

Question 28

Long-term potentiation (LTP)

Answer 28

Repeated firing of a synapse lowers the threshold for that synapse to fire

Question 29

Long-term potentiation (LTP) stages

Answer 29

Time 1 (before any change happens)
Stage 2 (induction)
Stage 3 (expression)

Question 30

Time 1 (before any change happens)
LTP

Answer 30

pre-synaptic neuron fires at a normal rate

post-synaptic neuron fires at a certain strength in response

Question 31

LTP – Stage 2 (induction)

Answer 31

Time 2  (the cause of the change)
pre-synaptic neuron fires a lot, causing post-synaptic neuron to fire a lot

Question 32

LTP – Stage 3 (expression)

Answer 32

Time 3 (after the change)

• presynaptic neuron fires at a normal rate
• post-synaptic neuron now fires more strongly than it did at Time 1

Question 33

Mechanisms of LTP

Answer 33

• The NMDA receptor is a receptor for glutamate
• the NMDA receptor does not respond maximally unless two events occur simultaneously
• NMDA receptors allow only small numbers of calcium ions to enter unless the neuron is already depolarised when glutamate binds to the receptors which triggers an action potential

Question 34

what are the 2 events needed for the NMDA to respond maximally

Answer 34

1. glutamate must bind to it

2. the postsynaptic neuron must already be partially depolarised