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Flashcards in learning and memory Deck (36)
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1
Q

what is learning?

A

the acquisition of new information

2
Q

what is memory?

A

retention of learned information

3
Q

2 types of memory?

A

declarative and non-declarative

4
Q

what is the difference between declarative and non declarative memory?

A

declarative is explicit, information you can verbally declare
-eg. date of birth, where you were born

non-declarative is implicit, about procedural memory
-eg. motor skills, habits, driving a car

5
Q

which brain regions are involved with non-declarative memory?

A

striatum is involved in procedural memory - skills and habits
cerebellum is involved in skeletal musculature
amygdala is involved in emotional responses

6
Q

types of declarative memory

A
  • working memory
  • short term memories
  • long term memories
7
Q

what is working memory?

A

temporary storage, lasts seconds

8
Q

what are short term memories?

A

more stable than working memory
vulnerable to disruption
facts and events stored in short-term memory

9
Q

what are long term memories?

A

recalled months or years later

10
Q

what happens to selective short term memories?

A

they become long term memories - stored in different parts of the brain

11
Q

location of the brain involved in working memory?

A

prefrontal lobe

12
Q

functions of the pre frontal cortex:

A
  • self-awareness

- capacity for planning and problem solving

13
Q

what was the method of the delayed response task?

A

-monkey sitting down, series of wells in front of them
-food placed in 1 of the wells, screen placed in front
-screen comes up, monkey remembers which well had the food in
“cue period” - monkey needs to retain the info in this period
“delay period” - monkey remembering where the food is
“choice period” - choosing the well

14
Q

what were the results of the delayed response task?

A

showed the role of the pre frontal cortex in working memory
-the information about which well had the food was retained for a short period of time
-increase in activity during the “delay period” -
sub populations of neurones in the pre frontal cortex have increased activity when the monkey is retaining the information in its short term memory

15
Q

delayed-saccade task

A

role of lateral intra-parietal cortex neurones in working memory

  • saccadic eye movements to the fixation point, monkey gets a reward if they get it right
  • saccadic eye movements enable you to scan the environment quickly
  • increase in neuronal firing during delay period
16
Q

where are memories stored?

A

the engram

17
Q

how are all the neurones interconnected?

A

via neural networks
-group of neurones firing together will lead to heavier modification of electrical circuits, strengthens connections between neurones

18
Q

what is meant by the term consolidation?

A

short term memory -> long term memory

19
Q

where is the hippocampus?

A

in the medial temporal lobe

20
Q

information flow through the medial temporal lobe

A

sensory info goes to cortical association area –> parahippocampal and rhinal cortical areas –> hippocampus –> thalamus and hypothalamus via the fornix

21
Q

what is the output pathway of the hippocampus and where does it go?

A

the fornix, goes to the hypothalamus and thalamus

22
Q

what is movement of sensory info through the media temporal lobe important for?

A

consolidation

23
Q

do memories stay in the hippocampus?

A

not necessarily, they can go to the thalamus and hypothalamus, which sort them out and send them to different regions of the cortex depending on what it is

24
Q

are all long term memories in the hippocampus?

A

no, they are also distributed across the brain in the form of engrams

25
Q

define amnesia?

A

serious loss of memory or ability to learn

26
Q

causes of amnesia?

A

concussion, chronic alcoholism, encephalitis, brain tumour, stroke

27
Q

types of amnesia?

A

retrograde
-problems with memories they had before the trauma

anterograde

  • problems with memories they have after the trauma
  • inability to form memories but long-term memories are stored
28
Q

what severely compromises hippocampal function?

A

removal of the medial temporal lobe

29
Q

consequence of viral encephalitis?

A

affected hippocampus, significant impairment to declarative memory
-stuck in a short loop

30
Q

spatial memory and place cells - experiment and results

A
  • Morris water maze
  • mouse in the water, has to swim around and get to the platform - can’t see because the water is cloudy
  • mouse will use navigational uses to get to the platform faster over time
  • if we block the neurones in the hippocampus, you will modulate the spatial neurones, so the mouse loses its navigational abilities
31
Q

2 models of memory consolidation

A
  1. standard model of memory consolidation
    - info sent from neocortex areas associated with sensory areas to medial temporal lobe for processing
    - synaptic consolidation
    - post consolidation, hippocampus not necessary
  2. multiple trace model of consolidation
    - hippocampal involvement is continued
    - multiple memory traces
    - more sophisticated, long-term memories can be modified - useful for PTSD when you want to change unpleasant memories
32
Q

memory is encoded…

A

….across a number of neurones

  • eg. when you see somebody, its not just cell A firing, its components from cell A, B and C
  • if a group of neurones stop working, the entire memory isn’t completely blocked out
33
Q

trisynaptic circuit

A
  • info flows from entorhinal cortex via performant path to the dentate gyrus
  • mossy fibres originate from dentate gyrus and synapse upon pyramidal neurones in CA3 hippocampal regions
  • axons from CA3 (Schaffer collaterals) synapse upon pyramidal neurones in CA1 hippocampal regions
34
Q

what happens in the CA1 hippocampal region?

A

LTP

35
Q

explain LTP

A

glutamate receptors located on CA1 neurones, ionotropic AMPA and NMDA receptors

  • glutamate released and binds to post synaptic cell
  • stimulation of AMPA receptors, Na+ influx
  • activation of NMDA receptors, Na+ and Ca2+ influx
  • calcium binds to calmodulin, calmodulin activates kinases
  • increased responsivity of AMPA receptors, increased trafficking of AMPA receptors to post-synaptic membrane
  • so more depolarisation occurs for a smaller glutamate release
36
Q

how does LTP affect dendrites?

A

long lasting structural changes, dendritic spine growth
-when hippocampal receptors express AMPA receptors, the dendrites swell because there is an increase in physical membrane area