neural basis of learning and memory

Question 1

what is neural plasticity?

Answer 1

• ability of the brain’s neural structure or function to be changed by experience throughout the lifespan

Question 2

how does neural & synaptic plasticity make learning and memory possible?

Answer 2

• def
• change involving synaptic plasticity that make it possible-> structural changes that physically enable brain to respond to experience and store this info to enable learning and memory
  eg. LTP/LTD, synapse formation/growth, reorganising existing connections, formation/strengthening of new neural pathways to represent learning/memory

Question 3

what is synaptic plasticity?

Answer 3

ability of the synapse to change over time

Question 4

what are examples of synapse formation/growth?

Answer 4

structural changes at the synapse
eg.
- axon terminal growth
- increased receptor sites
- more bushier dendrites and dendritic branches
functional changes:
- faster connections
- more neurotransmitters released
- formation of new and more synaptic connections

Question 5

what is long-term potentiation?

Answer 5

the long-lasting strengthing of synaptic connections, resulting in enhanced or more effective synaptic transmission
- caused by repeated stimulation

Question 6

what is the effect of long-term potentiation on neural communication

Answer 6

• def
• high level of stimulation= neurotransmitters repeatedly sent across synaptic gap
  = pre and postsynaptic neurons are coactivated
  = changes structure of synapse & strengthens connections between the two neurons
  = more likely to fire together again

Question 7

what is the role of long-term potentiation in learning and memory

Answer 7

• memories and neural pathways required to [action in scenario] are strengthened due to repeated practice
• LTP def
• easier to retrieve info & less likely to be forgotten

Question 8

what is long-term depression?

Answer 8

neural mechanism of learning that results in the long-lasting weakening of synaptic transmission
- caused by repeated, prolonged low-level stimulation

Question 9

what is the effect of long term depression on neural communication?

Answer 9

• low level stimulation= less opportunity for neurotransmitters to be released= weakened connections b/w neurons
• post-synaptic neurons become less responsive to neurotransmitters released
• weakens/eliminates synaptic connections if disuse continues
  = less likely to fire together at the same time in future

Question 10

what is the role of long term depression in the learning process?

Answer 10

• definition + why is it occurring
• involved in unlearning old skills
• LTD may lead to pruning/whithering/shrinking of unimportant/unused connections
• leaves important connections to be strengthened by LTP

Question 11

how does long-term depression contribute to the weakening of a CC response?

Answer 11

• def
• REPEATED presentation of CS without UCS= weakened input to post-synaptic neuron
• prolonged low-level stimulation= weakening of previously potentiated CR

Question 12

what is learning?

Answer 12

relatively permanent change in behaviour that occurs as a result of experience

Question 13

how is learning and memory interconnected?

Answer 13

memory: neurological changes occuring as a result of learning
learning: capability to modify info stored in memory

Question 14

what is hebb’s rule?

Answer 14

learning involves building and strengthening neural connections to enable groups of neurons to form neural pathways

Question 15

role of glutamate in long-term potentiation?

Answer 15

• main excitatory neurotransmitter= makes neurons more likely to fire
• increases stimulation of adjacent neurons= promotes growth & strengthening of synaptic connections
• when glutamate next secreted by PreSN= larger excitatory effect on PostSN because of previous chemical effects

Question 16

What are neurohormones?

Answer 16

• chemical messengers made by neurons and released from axon terminals into the bloodstream

Question 17

define consolidation

Answer 17

• biological process of making a newly formed memory stable and enduring after learning
• takes time
• vulnerable to disruption for at least 30 mins after learning

Question 18

define reconsolidation

Answer 18

• when retrieved memory is consolidated again

Question 19

what is the role of adrenaline in emotionally arousing experiences?

Answer 19

• enhance consolidation of emotionally arousing experiences to LTM
• during stressful experience= fight-flight response activated
• > releases adrenaline= induces release of noradrenaline in amygdala
• > signals to hippocampus explicit details of event is important & long term storage should be strengthened

Question 20

why are emotionally arousing experiences likely to be remembered?

Answer 20

• high lvl arousal involve fight-flight response= releases adrenaline
• adrenaline enhance ability to encode memory
  = more likely to be remembered

Question 21

Similarities & differences b/w neurotransmitters & neurohormones

Answer 21

S:
- sends info to target cells
- released from neurons
- both chemical messengers
D:
- released into bloodstream vs. synapse
- greater distance= slower effect vs. adjacent cells= quicker effect

Question 22

why are memories of emotional arousing experiences adaptive?

Answer 22

• inceases likelihood we avoid danger associated with arousal in future
  eg. memory of aggressive dog helps us show caution in future