Memory and Learning 1

Question 1

Define learning

Answer 1

Process whereby new info is acquired by the nervous system and leads to a change in behaviour

Question 2

Memory

Answer 2

The encoding, storage and retrieval of learned info

Question 3

Name the two modes of memory

Answer 3

Declarative and Non-declarative(Procedural)

Question 4

What is declarative memory?

Answer 4

memory available to consciousness and can be expressed by language i.e. can be declared

Question 5

What is non-declarative memory

Answer 5

memory that involves skills and associations that are acquired and retrieved at an unconscious level

Question 6

What are the types of non-declarative memory and where are they stored long-term?

Answer 6

Procedural-striatum
Motor skills-cerebellum
Emotional- amygdala

Question 7

What are the types of declarative memory and where are they stored long-term?

Answer 7

Episodic (events)
Semantic (facts)
Both stored in the medial temporal lobe diencephalon

Question 8

Name the three temporal types of modes of memory?

Answer 8

Immediate memory
Working memory
Long-term memory

Question 9

What is immediate memory and what are its features?

Answer 9

The ability to hold ongoing experiences for a fraction of a second
Large capacity, each sensory modality has its own ‘memory register’

Question 10

What is working memory and what are its features?

Answer 10

Ability to hold information in the mind for seconds to minutes while it is used to achieve a certain goal
Limited in duration and capacity

Question 11

What is long-term memory and what are its features?

Answer 11

Memory that is retained for days/weeks/lifetime

Immediate or working memory can enter long term memory by conscious or unconscious rehersal

Question 12

What is an engram?

Answer 12

The physical embodiment of memory in the neuronal machinery which depends on changes in synaptic connections and/or growth/reordering of these connections

Question 13

What is memory storage called?

Answer 13

Consolidation. Sensory info can go be consolidated to long term memory via short term memory or directly

Question 14

Forgetting

Answer 14

Unimportant info and unrehearsed memories deteriorate over time
Important not to retain everything, particularly immediate and working memories

Question 15

Importance of forgetting illustrated by Patient ‘S’

Answer 15

individual that cannot erase info- has difficulties distinguishing important cognitive stimuli from trivial info

Question 16

What is pathological forgetting called and how can it arise?

Answer 16

Amnesia

Arises from CNS injuries and disease

Question 17

What are the two types of amnesia?

Answer 17

Retrograde- loss of memories for events preceding the trauma with greater loss towards the time of trauma
Anterograde- continued loss of a large percentage of memory function after the time of the trauma,

Question 18

Case of H.M. anterograde amnesia

Answer 18

Bilateral medial temporal lobe resection
Amygdala, incus, hippocampal gyrus and anterior hippocampus removed to alleviate epilepsy
Resulted in profound loss of short term declarative memory function

Question 19

Case of R.B. anterograde amnesia

Answer 19

Ischaemic episode during surgery
Failed on tests on ability to form new declarative memories
Bilateral lesion of hippocampus, particularly CA1 regions

Question 20

What does declarative memory rely on?

Answer 20

Depends on the integrity of the hippocampus and its subcortical connections to the mammillary body and dorsal thalamus

Question 21

What is the route of declarative memory consolidation?

Answer 21

Cortical association areas —-> Parahippocampal and rhinal cortical areas ——> Hippocamus ———> Thalamus, hypothalamus via the fornix
AND
———–> feeds back to cortical association areas

Question 22

What structures are used to test spatial memory consolidation?

Answer 22

Morris water maze (invisible platform in pool)

and the radial arm maze (arms radiate from center area and some arms have food at end, others don’t)

Question 23

What are the effects of lesions on radial arm and spatial maze learning?

Answer 23

Lesions specific to hippocampus - marked effects

Perirhinal lesions - less effect

Question 24

Model for human episodic memory

Answer 24

Non-matching to sample, with or without delay

• train to visual stimulus, reward choice of non-matching pattern
• tests working memory and how long the memory is retained

Question 25

What are the effects of lesions on delayed matching and non-matching to sample?

Answer 25

Lesions restricted to hippocampus - very little effect

Perirhinal cortical lesions- profound effect on performance (much reduced mean percentage correct)

Question 26

Long term memory storage and retrograde amnesia

Answer 26

Tells us about how and where memories are stored
Typically involves lesions from trauma or neurodegenerative diseases e.g. Alzheimer’s
Suggests long term memory storage is distributed through the cerebral cortex

Question 27

Karl Lashley’s experiments

Answer 27

1920s
Searching for food reward in maze
Cortical lesions made, the larger the lesion the worse the performance
Long term memory stored in networks through cortex

Question 28

Long term declarative memory storage

Answer 28

fMRI studies - Bird and car images shown to bird and car experts
Declarative memories stored in specific cortical regions

Question 29

How do we acquire non-declarative memories?

Answer 29

Conditioned learning

Question 30

What is conditioned learning?

Answer 30

Generation of a novel response that arises from paring a novel stimulus with the stimulus that generates the response being studied

Question 31

What are the two types of conditioned learning?

Answer 31

Classical conditioning and Operant conditioning

Question 32

What is classical conditioning and how does it work?

Answer 32

An innate reflex (e.g. dog salivates in response to food) is modified by associating its normal triggering stimulus (e.g. food) with an unrelated stimulus (e.g. a bell).
By ringing the bell when the dog is presented with food, the dog will learn to salivate in response to the ringing of the bell even without food being present

Question 33

What is operant conditioning and how does it work?

Answer 33

Alter the probability of a response by associating it with a reward/punishment
Developed by Frederick Skinner - Skinner’s box
Mouse learns to push lever to get food or gets a foot shock and learns where not to step

Question 34

Testing where non-declarative memories are stored using conditioned responses

Answer 34

Emotion- classical fear conditioning (amygdala) - Foot shock associated with stimulus, give foot shock and animal freezes, eventually animal will freeze in response to stimulus alone

Motor skills - classical eye blinking conditioning (cerebellum) Tone followed by puff of air-> eye blink. Tone alone —> eye blink

Procedural memory- (basal ganglia) subjects learn that selecting e.g. pink door in condition A leads to reward and then learn the doors to select in conditions B,C and D to get to the reward so that overall path is D->C->B->A->reward.
Parkinson’s patients with dopamine replacement therapy do almost as well as controls, but those not on therapy have impaired ability to learn the task

Question 35

What is phylogenetic memory and how does it arise/become established?

Answer 35

Memories stored in genes
Arise from the experiences of a species over eras
Established by natural selection acting on neural development

Question 36

Association and motivation in memory

Answer 36

Working memory = can remember 7-9 numbers, with association and motivation -> 80 numbers.
Motivated memory is modality dependent e.g. food>non-food, hungry>sated
Memory capacity also depends on the meaningfulness and perceived importance of the info to the subject
e.g. memorise piece positions in real chess game - % correct master>beginner, memorise pieces randomly arranged - % correct beginner>master