Memory

Question 1

learning =

Answer 1

acquisition of information

Question 2

memory =

Answer 2

storage of learnt information

Question 3

recall =

Answer 3

requisition of stored information

Question 4

the engram =

Answer 4

physical embodiment of memory

Question 5

independant memory systems

Answer 5

different forms of memory stored in different ways/regions/pathways
e.g. playing piano - auditory cortex and motor cortex

Question 6

procedural memory

Answer 6

skills and associations largely unavailable to concious mind

Question 7

declaritive memory

Answer 7

available to concious mind

can be encoded in symbols and language

Question 8

explicit memory

Answer 8

memory that can be coniously recalled

Question 9

implicit

Answer 9

memory that cannot be conciously recalled
different types:
- procedural memory
- classical conditioning
- priming

Question 10

memory duration

Answer 10

immediate - few seconds
short term - seconds or mins
- working memory
long term - days, months, lifetime

Question 11

temporal lobe and memory

Answer 11

electrical stimulation - hallucinations and recollection of the past experiences
epileptic seizures - complex sensations and memories
patient HM - temporal lobectomy
8cm of medial temporal lobe was removed
intelligence, personality intact etc
epilepsy stopped
extreme anterograde amnesia - cannot form new memories

Question 12

important structures

Answer 12

pre frontal cortex - working memory
hippocampus - converting short to long term memory, declaritive memory
amygdala - multiple processed sensory input (smell), implicit/emotional/learnt fear
cerebellum - procedural memory, sensorimotor

Question 13

hippocampus

Answer 13

hippocampul lesions caused memory loss
three layered cortex
- inputs from entorhinal cortex and beyond
- outputs many regions
- enlarged in people whose work requires good spatial memory

Question 14

mechanisms of memory

Answer 14

long term storage seems to be distributed
reverberating circuits - idea that memory is constant activity of neurons - not supported by experiemtal evidence
instead …. the hebbian synapse concept - change in synapse number between neurons
- activity modifiable, plastic synapses

Question 15

memory and synaptic plasticity

Answer 15

synaptic strength changes
facilitation / depression
- short term - mins/hrs —> Ca availability/vesicle depletion
- long term - days/weeks

Question 16

long term potentiation (facilitation)

Answer 16

studied in hippocampus slices
= increase in synaptic strength
CA3 - presynaptic neurons
CA1 - postsynaptic neuron
stimulate presyn with short high frequency bursts - EPSP increases
changes in synapses are very local, specifc pathway

Question 17

long term depression

Answer 17

in hippocapmus

EPSP amplitude decreases with time with a prolonged low frequency stimulation of presyn

Question 18

aplysia californica

Answer 18

large snail
gill withdrawl reflex
small number of neurons

Question 19

short term habituation and sensitisation

Answer 19

repeated gentle stimulation to siphon causes reduced gill withdrawal
- habituation
pair single tail pinch with siphon touch - leads to increased withdrawl of gill
- re establish siphone reflex, short term 60 mins +

Question 20

long term sensitisation

Answer 20

repeated pairing of siphon touch and tail pinch

- long term, non habituating siphon/gill reflex

Question 21

long term potentiation, depression and aplysia

Answer 21

require receptor activation (glutamate/seratonin)
altered synapse responses
mediated by second messenger (Ca/cAMP)
require protein phosphorylation changes in early stages
require protein synthesis for late stages
involve biochemical and structural pre and post syn changes

Question 22

how does long term potentiation occur?

Answer 22

evidence suggests often a post syn event
most indicates a critical role for Ca
involves trafficking of AMPA receptors to post syn membrane = inc in ESPS