Memory and Cognitive Thinking

Question 1

What is cognition?

Answer 1

Relates to highest order of brain function and relates to behaviour that deals with though processing
Is the integration of all sensory information to make sense of a situation

Question 2

What does making sense require?

Answer 2

Remembering events and learning from them which requires motivation

Question 3

Describe the association areas of the brain

Answer 3

Integrate information from multiple sources, rather than being concerned with one specific subject
Multiple parallel processing units
Processing required for cognition

Question 4

What are the main association areas of the brain?

Answer 4

Motor
Prefrontal
Sensory
Visual
Auditory

Question 5

What are the 3 components of learning and memory?

Answer 5

Hippocampus - formation of memories
Cortex - storage of memories
Thalamus - searches and assesses memories

Question 6

Where are memories formed?

Answer 6

In the limbic system
Has important connection with neo cortex, in temporal and frontal lobes - makes situations of info through learning

Question 7

What is the main function of the limbic system?

Answer 7

Gives emotional significance to events - essential for memory

Question 8

What are the 4 distinct areas of the limbic system?

Answer 8

Hypothalamus - ANS responses
Hippocampus - memory
Cingulate gyrus
Amygdala - emotion

Question 9

What are the areas of limbic system responsible for?

Answer 9

Instinctive behaviour - thirst, sex, hunger and emotional behaviours are driven by seeking reward or avoiding punishment

Question 10

What are the 2 areas of the limbic system?

Answer 10

Reward areas - intense feelings of well being, euphoria and sexual arousal
Punishment areas - fear/terror, anger or pain
These are central aspects for learning

Question 11

What happens to experiences that are neither rewarding or punishing?

Answer 11

They are barely remembered as insignificant - forgotten
Frontal cortex of brain assesses the significance of the event

Question 12

Describe the hippocampus

Answer 12

All sensory info comes through here
In turn it relays the info to other limbic system structures
Is essential for formation of memories

Question 13

What happens if you have bilateral hippocampal damage?

Answer 13

Have immediate sensory memory and intact long term memory from before damage but unable to form new long term memories
Reflective memory remains intact

Question 14

What can memory be divided into?

Answer 14

Immediate or sensory memory
Short term memory
Immediate long term memory
Long term memory

Question 15

What is immediate or sensory memory?

Answer 15

A few seconds
Ability to hold experiences in mind for a few seconds based on different sensory modalities
Visual memories delay fast and auditory is slowest

Question 16

What is short term memory?

Answer 16

Seconds to hours - called working memory
Used for short term tasks - phone numbers, mental arithmetic, sentence
Associated with reverberating circuits

Question 17

What is immediate long term memory?

Answer 17

Hours to weeks
Associated with chemical adaption at the presynaptic terminal

Question 18

What is long term memory?

Answer 18

Can be life long
Associated with structural changes in synaptic connections

Question 19

Describe short term memory and reverberating circuits

Answer 19

Each synapse in a reverberating circuit is excitatory and hence a brief excitatory stimulus causing long lasting neuronal activity in all neurons of pathway

Question 20

What is the short term memory is deemed significant?

Answer 20

Reverberation results in consolidation of the memory into long term memory storage

Question 21

What if reverberation is disrupted?

Answer 21

Memory loss - amnesia
Usually if effect to hippocampus or thalamus

Question 22

What are the 2 types of amnesia?

Answer 22

Anterograde - cannot form new memories
Retrograde - cannot access old memories

Question 23

Describe anterograde amnesia

Answer 23

Inability to recall events that happen after the injury
Can be short lived or permanent
Destruction of hippocampus - permanent inability to form new memories

Question 24

Describe retrograde amnesia

Answer 24

Cant remember events leading up to the injury but events that happened a long time ago can be recalled - as more deeply imbedded

Question 25

What happens if hippocampus is spared but thalamus damaged?

Answer 25

Retrograde amnesia seen

Question 26

Describe the chemical changes in presynaptic terminal in intermediate long term memory

Answer 26

Increasing Ca entry to presynaptic terminals which increases neurotransmitter release

Question 27

What structural changes at synapses are involved in long term memory?

Answer 27

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

Question 28

Describe long term potentiation

Answer 28

Increased amplitude in graded membrane potential in post synaptic cell - strengthens the synapse Forms basis of much learning and memory

Question 29

What are the 2 main types of long term memory?

Answer 29

Declarative or explicit memory Procedural/ reflective/ implicit memory

Question 30

Describe declarative or explicit memory

Answer 30

Abstract memory for events and for words, rules and languages Relies heavily on hippocampus

Question 31

Describe procedural/ reflective/ implicit memory

Answer 31

Acquired slowly through repetition Includes motor memory for acquired motor skills Biased mainly in cerebellum and is independent of hippocampus

Question 32

Describe consolidation

Answer 32

How short term memory is converted to long term memory Involves selective strengthening of synaptic connection through repetition - during this period memory is vulnerable of being wiped out

Question 33

What is memory recall dependant on?

Answer 33

Significance of events - brain gives attention to significant events

Question 34

Where are new memories stored?

Answer 34

Coded then stored in sensory and association areas of cortex Coding results in new memories being stored by others that seem similar

Question 35

What happens if experience is considered useful?

Answer 35

The frontal cortex gates the papez circuit - which includes hippocampus, mammillary bodies, anterior thalamus and cingulate gyrus in circle

Question 36

Where does reverberating activity continue between?

Answer 36

Papez circuit, frontal cortex, sensory and association areas until consolidation process is complete

Question 37

Where is each component of memory stored?

Answer 37

In different relevant parts of cortex

Question 38

Describe Korsakoff's syndrome

Answer 38

Chronic alcoholism - there is a vitamin B1 deficiency which leads to damage of limbic system structures so ability to consolidate memory is impaired

Question 39

Describe Alzheimer's disease

Answer 39

Severe loss of cholinergic neurons through out the brain including the hippocampus Gross impairment on memory Anti-cholinesterase can help

Question 40

Describe REM sleep and memory

Answer 40

Is important for memory - dreaming may enable memory consolidation and reinforce weak circuits