Memory and Cognition

Question 1

what is cognition?

Answer 1

Cognition describes the integration of all sensory information to make sense of a situation.

Cognition relates to the highest order of brain function and relates to behaviour that deals with thought processing

Question 2

whats the function of association areas?

Answer 2

integrate information from multiple sources, rather than being concerned with one specific function

The brain can therefore be thought of as multiple parallel processing units

Question 3

what are the 3 components of learning and memory?

Answer 3

Hippocampus – formation of memories

Cortex – storage of memories

Thalamus – searches and accesses memories

Question 4

function of the limbic system?

Answer 4

gives events emotional significance – essential for memory.

Question 5

what is the most primitive part of the cortex?

Answer 5

limbic system

Question 6

what are the 4 distinct areas of the limbic system?

Answer 6

hypothalamus (assoc. with ANS responses), hippocampus (assoc. with memory), cingulate gyrus and the amygdala (assoc. with emotion).

Question 7

what happens when there is an electric stimulation of certain areas in the limbic system?

Answer 7

intense feelings of well being, euphoria and sexual arousal = reward areas

Question 8

what are punishment areas?

Answer 8

Other nearby areas elicit fear/terror, anger or pain

Question 9

what forms the “affective components” of sensory experiences?

Answer 9

Reward and punishment

Question 10

what does almost all sensory information go through?

Answer 10

the hippocampus

Question 11

what happens to people with bilateral hippocampal damage?

Answer 11

have immediate (sensory) memory (seconds in length) and intact long-term memory (from time before damage), but are unable to form new long-term memories.

Their reflexive memory (motor skills) remains intact.

The effect is totally devastating.

Question 12

what can memory be divided into?

Answer 12

Immediate or Sensory memory
Short-term memory
Intermediate long-term memory
Long-term memory

Question 13

what is Immediate or Sensory memory

Answer 13

a few seconds. Describes the ability to hold experiences in the mind for a few seconds. Based on different sensory modalities. Visual memories decay fastest (<1s), auditory ones slowest (<4s).

Question 14

what is Short-term memory

Answer 14

seconds - hours. Often called Working Memory. Brain’s “post-it note”. Used for short term tasks such as dialling a phone number, mental arithmetic, reading a sentence. Associated with reverberating circuits.

Question 15

what is Intermediate long-term memory

Answer 15

hours to weeks e.g. what you did last weekend. Associated with chemical adaptation at the presynaptic terminal.

Question 16

what is Long-term memory

Answer 16

can be lifelong. e.g. where you grew up and your childhood friends. Associated with structural changes in synaptic connections.

Question 17

short-termed memory is an electrical phenomenon, what does it depend on?

Answer 17

depends on maintained excitation from reverberating circuits

Question 18

what keeps the brief short term memory alive?

Answer 18

the reverberating circuit

Question 19

what happens when the reverberation is disrupted e.g. following a head injury or infection?

Answer 19

memory loss normally results – amnesia

Question 20

what are the two types of amnesia?

Answer 20

Anterograde

Retrograde

Question 21

what is the difference between anterograde and retrograde?

Answer 21

Anterograde – cannot form new memories

Retrograde – cannot access (more recent) old memories

Question 22

what is anterograde amnesia?

Answer 22

inability to recall events that happen after the injury. Depending on the severity of the injury this can be short lived or permanent. Destruction of the hippocampus (as with Clive Wearing) results in permanent inability to form new memories.

Question 23

what is retrograde amnesia?

Answer 23

can’t remember events leading up to the injury, although recall of events that happened a long time ago is usually unaffected, probably because they are better rehearsed and more deeply imbedded.

Retrograde amnesia often presents with anterograde amnesia. However, interestingly, if only the thalamus is damaged, and the hippocampus spared, only retrograde amnesia is seen. Suggests thalamus is required for “searching” our existing memory bank.

Question 24

the intermediate long term memory involves chemical changes in….

Answer 24

presynaptic neurons

Question 25

increaseing calcium entry to presynaptic terminals ….. neurotransmitter release

Answer 25

increases

Question 26

what structural changes at synapse does long-term memory involve?

Answer 26

Increase in NT release sites on presynaptic membrane.
Increase in number of NT vesicles stored and released.
Increase in number of presynaptic terminals

Question 27

what is long-term potentiation?

Answer 27

increased amplitude in graded membrane potential (EPSP) in the post-synaptic cell is often observed. This “strengthens the synapse”, is called Long Term Potentiation

Question 28

what does the long term potentiation form the basis of?

Answer 28

basis of much learning and memory

Question 29

what is the name of a well established, well rehearsed pattern of neuronal firing unique to that particular memory

Answer 29

long term potentiation

Question 30

whatare the two main types of long term memory?

Answer 30

Declarative or Explicit Memory:

Procedural/ Reflexive/Implicit Memory:

Question 31

what is Declarative or Explicit Memory?

Answer 31

Abstract memory for events (episodic memory) and for words, rules and language (semantic memory).
Relies heavily on the hippocampus

Question 32

what is Procedural/ Reflexive/Implicit Memory

Answer 32

Acquired slowly through repetition. Includes motor memory for acquired motor skills such as playing tennis, and rules based learning such as, in the UK, always driving on the left.

Thinking about these skills (“memories”) often impairs performance!

Is based mainly in the cerebellum.

Is independent of hippocampus (remember Clive Wearing).

Question 33

how is short term memory converted to long term memory?

Answer 33

through consolidation

Question 34

what does consolidation involve?

Answer 34

selective strengthening of synaptic connections through repetition

Question 35

what is the papez circuit?

Answer 35

hippocampus–> mamillary bodies–> anterior thalamus—> cingulate gyrus—-> hippocampus

Question 36

what is the association with the olfactory system and limbic system?

Answer 36

Olfactory stimuli are relayed via the olfactory tract to the primary olfactory cortex where substantial connections to the amygdala and hippocampus are found.

This association with the limbic system, and hippocampus in particular, explains why smells are especially powerful in evoking long term memories.

Question 37

what is korsakoffs syndrome?

Answer 37

there is Vitamin B1 deficiency which leads to damage of limbic system structures. The ability to consolidate memory is impaired.