11 - Learning And Memory

Question 1

Learning vs memory

Answer 1

Learning: acquiring new information
Memory: store and retrieve information
Learning and memory are closely related; cannot be sure learning has occurred without memory

Question 2

Classical conditioning

Answer 2

Associative learning
Ivan Pavlov
Pairing two stimuli changes the response to one of them
Conditioned and unconditioned stimuli

Question 3

Operant conditioning

Answer 3

Individuals response followed by reinforcer or punishment
Reinforcer: events that increase the probability that the response will occur again
Punishment: events that decrease the probability that the response will occur again

Question 4

Engram

Answer 4

Physical representation of learning

Question 5

Engram - Descartes

Answer 5

Descartes is suggested as the first to consider the physical representation of learning
Considered the pineal glands as the master controller
Animal spirits move through the brain through pores and tubes
Easier for the spirits to move through pores which have previously been opened

Question 6

Engram - Lashley

Answer 6

Karl Lashley proposed that severing connections between brain regions should abolish learning
Based on the assumption that learning depends on connections between brain regions
Cuts through cortical regions produced no consistent impairments in learning in rats
Never found the engram

Question 7

Lashley’s principles about the nervous system

Answer 7

Equipotentiality: all parts of the cortex contribute equally to complex functioning behaviours (eg learning)
Mass action: the cortex works as a whole, and more cortex is better

Question 8

Engram - Thompson

Answer 8

Thompson and colleagues proposed that the classical conditioning engram is located in the cerebellum
Lateral interpositus nucleus (sub-section of cerebellum) identified as central for learning
Responses increase as learning proceeds
Temporary inactivation resulted in no learning

Question 9

Types of memory - Donald Hebb

Answer 9

Donald Hebb supported the assumption that memory and learning relies on a physical change
Differentiated between two types of memory:
Short-term memory: memory of recent events
Long-term memory: memory of distant events

Question 10

Consolidation of memory

Answer 10

Consolidation from short-term to long-term memory is suggested to rely on protein synthesis
Inhibition of transcription/translation results in amnesia
However, consolidation is likely a complex process
Significant variability in the time taken for consolidation - e.g. Emotional events

Question 11

Working memory components

Answer 11

Proposed by Baddeley and Hitch as an alternative to short-term memory
Consists of:
Phonological loop
Visuospatial sketchpad
Episodic buffer (brings all parts together)
Executive control

Question 12

Working memory assessed and damage

Answer 12

Assessed using the delayed response task
Requires responding to something you heard or saw a short while ago
Damage to the prefrontal cortex produced impairments in performance on the delayed response task

Question 13

Hippocampus and amnesia

Answer 13

H.M. suffered from severe epilepsy
The hippocampus, amygdala, and parts of the temporal lobe were removed from both hemispheres
H.M. suffered significant memory impairment
But impairment was not consistent across all memory domains

Question 14

H.M.’s memory

Answer 14

Severe anterograde amnesia and some retrograde amnesia
Unimpaired working (short term) memory
Severe loss of episodic memories
Better implicit memory
Largely intact procedural memory

Question 15

Anterograde amnesia

Answer 15

Loss of ability to form new memory after the brain damage

Question 16

Retrograde amnesia

Answer 16

Loss of memory of events prior to the occurrence of the brain damage

Question 17

Semantic memory

Answer 17

Memories of factual information - general knowledge

H.M. showed impaired semantic memory, but was able to form some weak semantic memories

Question 18

Episodic memory

Answer 18

Memories of single personal events

H.M. could not describe any event since his surgery

Question 19

Explicit memory

Answer 19

Deliberate recall of information that one recognises as a memory
Most impaired in H.M.

Question 20

Implicit memory

Answer 20

The influence of experience on behaviour even if one does not recognise that influence
Assessed using priming tasks
Procedural memory

Question 21

Korsakoff’s syndrome

Answer 21

Memory disorder typically resulting from Wernicke’s encephalopathy
Causes by brain damage in response to prolonged thiamine deficiency
Impedes brain’s ability to use glucose
Leads to neural damage in regions surrounding the ventricles
Symptoms:
Confabulation (taking guesses to fill in gaps in memory), confusion, memory loss

Question 22

Alzheimers Disease

Answer 22

Is a type of dementia characterised by a gradual decline in memory
Neural degeneration seen throughout both cortical and subcortical regions
Associated with changes at a cellular level:
Beta-amyloid
Tau protein

Question 23

Accumulation of the beta-amyloid and tau protein results in:

Answer 23

Plaques: structures formed from damaged axons and dendrites (beta-amyloid)
Tangles: structures formed from degeneration within neurons (tau protein)

Question 24

Basal ganglia & memory

Answer 24

Gradual learning realise on the basal ganglia
Damage to the basal ganglia prevents gradual learning
Weather prediction game

Question 25

Amygdala & memory

Answer 25

Associated with fear learning

Inhibition of protein formation in the amygdala interrupts consolidation

Question 26

Parietal lobe & memory

Answer 26

Associated with piecing together aspects of episodic memory

Free recall impairments

Question 27

Anterior temporal cortex & memory

Answer 27

Damage to the anterior temporal cortex results in loss of semantic memory
Semantic dementia

Question 28

Prefrontal cortex & memory

Answer 28

Involved in learned behaviour and decision-making

Initiates top-down influence for working memory

Question 29

Neuronal changes and learning

Answer 29

Patterns of activity in the brain leave a path of physical changes
Physical changes can take place at many different sites to cause a change in the size of the postsynaptic potential
Presynaptic, postsynaptic or both
Can result in greater neurotransmitter release
More receptors or receptors become more sensitive

Question 30

Learning and the Hebbian synapse

Answer 30

“Neurons that fire together wire together”
A synapse that increases in effectiveness because of simultaneous activity in the presynaptic and postsynaptic neurons
Such synapses may be critical for many kinds of associative learning

Question 31

Long-Term Potentiation in Vertebrates

Answer 31

LTP occurs when one or more axons bombard a dendrite with stimulation
Leave the synapse ‘potentiated’ for a period of time and the neuron is more responsive

Question 32

Long-Term Depression (LTD)

Answer 32

A prolonged decrease in response at a synapse that occurs when axons have been less active than others
Compensatory process: (can’t have brain constantly strengthening) as one synapse strengthens, another weakens
Lack of activity within a network causes weakening of synaptic connection

Question 33

Biochemical mechanisms

Answer 33

Studies most in the hippocampus 
LTP depends on changes at glutamate synapses
Two types of glutamate receptions:
AMPA receptors
NMDA receptors

Question 34

The LTP process in hippocampal neurons

Answer 34

See book and slides

Question 35

LTP and memory

Answer 35

LTP is proposed as one of the many neuronal mechanisms likely to underlie memory construction and storage
LTP process has similar time course to short term and long term memory
Blocking LTP impairs learning
Genetic manipulation in mice to increase number of NMDA receptors results in enhanced learning capacity
Performing learning tasks activates LTP-like processes