10: The Remembering Brain 1

Question 1

what are the 2 types of long-term memory?

Answer 1

declarative (explicit) & non-declarative (implicit)

Question 2

what are the 2 types of declarative/explicit memory?

Answer 2

episodic & semantic

Question 3

what are the 4 types of nondeclarative/implict memory?

Answer 3

procedural
perceptual representation system
classical conditioning
nonassociative learning

Question 4

which 3 areas of the brain are associated with declarative memory?

Answer 4

medial temporal lobe
middle diencephalon
neocortex

Question 5

what distinguishes autobiographical memory from episodic memory?

Answer 5

autobiographical memory encompasses both episodic and semantic memory

Question 6

what are the 3 parts of the medial temporal lobe?

Answer 6

hippocampus
entorhinal cortex
para hippocampal gyrus

Question 7

what are the 3 segments on the parahippocampal gyrus

Answer 7

rhinal sulcus, perirhinal cortex & parahippocampal cortex

Question 8

what is the order of information flow within the medial temporal lobe?

Answer 8

perirhinal and parahippocampal cortex -> entorhinal cortex -> hippocampus
- all areas perform information processing

Question 8

define: anterograde amnesia

Answer 8

Difficulties in acquiring new memories

Question 9

define: retrograde amnesia

Answer 9

difficulties remembering events from before their brain injury

Question 10

what were HM’s symptoms?

Answer 10

Minor retrograde amnesia (for events within the 2 years preceding the surgery)
Profound anterograde amnesia: could not form long-term memories for events after surgery
- limited to declarative/explicit memory
- Global amnesia: affecting all sensory
modalities

Question 11

what is the medial temporal lobe’s role in memory?

Answer 11

critical for making new memories and retrieving old

Question 12

what is the subsequent memory paradigm used for?

Answer 12

evaluate encoding-phase activity leading to successful versus unsuccessful memory

Question 13

what part of the PFC is predictive of later remembered/forgotten stimuli?

Answer 13

left ventrolateral PFC

Question 14

what is the perirhinal cortex’s role in declarative memory?

Answer 14

processes item representations (important for
familiarity)

Question 15

what is the parahippocampal cortex’s role in declarative memory?

Answer 15

process “context” (including scene perception)

Question 16

what is the hippocamus’ role in declarative memory?

Answer 16

binds items in context (important for recollection).

Question 17

which part of the medial temporal lobe predicts familiarity-based recognition?

Answer 17

perirhinal cortex

Question 18

which part of the medial temporal lobe predicts recollection-based recognition?

Answer 18

hippocampus

Question 19

define: consolidation

Answer 19

process that stabilises a memory over time after it is first acquired

Question 20

what is involved with synaptic consolidation?

Answer 20

§ Structural changes in the synaptic connections between neurons
§ May take hours – days to complete

Question 21

what is involved in system consolidation?

Answer 21

Gradual shift of memory from hippocampus to the cortex

Question 22

what are the two theories of system consolidation (related to hippocampal function)

Answer 22

Standard consolidation theory: Temporary role of hippocampus
Multiple trace theory: Permanent role of the hippocampus

Question 23

what is ribot’s law?

Answer 23

Memory loss following brain damage has a
temporal gradient
More recent memories are more likely to be
lost than remote memories

Question 24

what is the explanation for ribot’s law?

Answer 24

remote memories have undergone systems consolidation – they do not rely upon the MTL anymore, but are cortex -dependent

Question 25

what characterises Korsakoff’s syndrome?

Answer 25

problems learning new information, inability to remember recent events and long-term memory gaps - temporal gradient in amnesia

Question 26

explain the standard consolidation model of declarative memory

Answer 26

• The hippocampus links together different kinds of information in many regions of brain (perceptual, affective, conceptual etc.)
• Hypothesis: Initially, hippocampus plays an active role in ‘binding’ the activity of disparate cortical ‘modules’
• Over time, the hippocampus plays less of a role

Question 27

how does a memory change from hippocampus to cortex dependent?

Answer 27

memory reactivation - iteratively leads to stabilisation & refinement

Question 28

when a memory has been consolidated, where does the memory cue retrieve the memory from?

Answer 28

cortical network

Question 29

where in the brain is semantic dementia linked to atrophy?

Answer 29

temporal lobes (cortex)

Question 30

what characterises semantic dementia?

Answer 30

can remember recent but not old events because memories not yet completely dependent on cortex – yet to be transferred out of hippocampus

Question 31

where in the brain is related to Alzheimer’s?

Answer 31

hippocampus & related structures

Question 32

what is the multiple trace theory of system consolidation (related to hippocampal function)

Answer 32

• The hippocampus never ceases to have an important role in episodic memory recall
• Older memories have been reactivated many times over the years
• Each reactivation creates new traces in the MTL and in other neocortical structures
• To the extent that damage is not global, older
• memories are more likely to be remembered as they have multiple traces
• Older memories become more semantic-like
  e.g., stories without episodic detail

Question 33

how does retrograde amnesia evidence the standard consolidation theory of memory consolidation?

Answer 33

the temporal gradient of amnesia reflect the temporal gradient of transfer of memory to the cortex

Question 34

what is the fMRI evidence of hippocampus activity related to episodic memory?

Answer 34

• Hippocampus activated for both recent and remote memories
• Hippocampal activation was related to the richness of re-experiencing (vividness) rather than the age of the memory per se
• backs up multiple trace theory

Question 35

what is the difference between recollection-based recognition & familiarity-based recognition?

Answer 35

recollection-based recognition = hippocampus for everything
familiarity-based recognition = specialisation across the MTL (eg faces in amygdala and scenes somewhere else)