Lecture 10 - learning and memory part 1

Question 1

classical conditioning

Answer 1

where animals and humans can associate a specific stimuli with some positive or negative rewards and act accordingly

Question 2

what is habituation?

Answer 2

where you get used to the stimulus so the response to it decreases

Question 3

what is sensitisation?

Answer 3

leads to increase in amplitude in response. if its a weak response to begin with, once the response becomes bigger and bigger

Question 4

what are the two organs the aplysia wants to protect?

Answer 4

siphon and gill

Question 5

what causes the withdrawal of the gill?

Answer 5

puff of water on the siphon

Question 6

what happens if the puff of water stimulus is repeated several times?

Answer 6

the reflex completely disappears or is massively reduced

Question 7

reflex circuit for the gill withdrawal reflex?

Answer 7

stimulate skin to activate the sensory neuron and then the motor neuron is activated (glutaminergic) and it depolarises and causes the gill muscle to contract

Question 8

possible origins of habituation

Answer 8

located somewhere in the synapses between the presynaptic and postsynaptic neuron

Question 9

cellular basis of habituation

Answer 9

• proximal pool takes time to diffuse and become a ready releasable pool (RRP) and reserved pool takes even more time

Question 10

what happens during habituation?

Answer 10

the RRP is released and there is less viable vesicles in the active zone to be released in the next presentation of the stimulus

Question 11

what effect does sensitisation have on the withdrawal reflex?

Answer 11

increases the withdrawal reflex and involves presynpatic input and molecules like serotonin and G-protein action

Question 12

what is L29

Answer 12

a sensory neuron which binds to other sensory neuron which is postsynaptic with L29 and presynaptic for the motor neuron

Question 13

what happens with sensitisation inside the synapses?

Answer 13

sensitisation is serotoninergic and activates adenylyl cyclase which produces cAMP and activates protein kinase A which phosphorylates a protein to change its conformation and leads to change to function

Question 14

what does protein kinase A inactivate?

Answer 14

potassium channels which leads to longer depolarisation. means more synpatic vesicles are released in the presynapse

Question 15

what is associative learning?

Answer 15

associate conditional stimulus with unconditonal stimulus and these have to happen at the same time

Question 16

associate learning with gill withdrawal reflex

Answer 16

associate condition stimulus (touch) and unconditional is the shock. pairing the two stimuli, the gill withdrawal reflex is even larger and lasts longer

Question 17

what happens when the two neurons work together in associative learning (sensitisation)?

Answer 17

L29 releases transmitter and the sensory neuron is also depolarised which causes a calcium influx into synpase and activates additional activity of adenylyl cyclase and produces more cAMP and en even higher release at teh synapse between sensory and motor neuron

Question 18

the three main protein kinases in sensitisation and conditioning (early stages)?

Answer 18

protein kinase A
protein kinase C
Camk2 (activated by calcium)

Question 19

what produces the molecules which activates the protein kinases

Answer 19

G-proteins, tyrosine kinases or calcium ions
- serotonin activates phospholipase C

Question 20

what is MAPK (late stages)

Answer 20

its a protein kinase that travels from cytoplasm into the nucleus and causes gene expression. some proteins are diffusing or transported to synapse