L9 - learning and memory Flashcards
what are the types of memory
declarative
non-declarative
long term
short term
what is declarative memory
facts - can memorise
what is non-declarative memory
skill
what do the presynaptic vesicles contain
glutamate or GABA
what are the functions of synaptobrevin, SNAP24 and syntaxin
snares that interact with each other and bring the synaptic vesicle close to the membrane and leads to fusion
what. is synaptotagmin
calcium sensor, senses increase in calcium in the pre-synaptic site. it triggers the release of the neurotransmitter
what does the distance from the calcium channel to the synaptic vesicle release site regulate
regulates the amount of synaptic vesicles that can be released
what is synaptotagmin regulated by
proteins and cytoskeleton molecules
this regulation is plastic so there can be modification of the proteins which regulate the distance of the synaptic vesicle to the calcium channel
what are the 3 main pools of vesicles
readily releasable pool
proximal pool
reserve pool
what is the readily releasable pool
as soon as calcium concentrations got sip, these vesicles are ready to be released
what is the proximal pool
gets turned into readily releasable pool - slightly larger population
what is the reserve pool
gets turned into the proximal pool - even larger population
what are the 3 types of glutamate receptors
NMDA
AMPA
mGluR
what is AMPA most permeable to
sodium and potassium
what does opening of AMPA lead to
depolarisation of the neuron
what is NMDA most permeable to
calcium
what does NMDA receptor lead allow
increase of calcium inside the post-synaptic buton
what is habituation
memory that allows the nervous system to stop responding to a stimulus that is repetitively appearing
what is sensitisation
opposite of habituation - if stimulus is constant and important then the NS responds more
4 examples of habituation in humans
habituation of eye blink reflex
habituation of repetitive non harmful stimulus
habituation of visual attention
habituation of emotional response
what are the two important organs of aplysia
gill and the siphon (used for locomotion) contains lots of sensory neurons
have developed a gill reflex when the siphon is touched
outline habituation in aplysia
repeated stimuli (10-15 times, intervals of 10-60s) get a reduction of the reflex - occurs at the abdominal ganglion synapse
what is the cellular basis of habituation
habituation results from a reduced synaptic strength
>50% lower quantal release
what happens if habituation is done at the postsynaptic neuron
the results become smaller and smaller, therefore a change between the presynaptic and postsynaptic neuron in behaviour.
outline sensitisation in aplysia
if perform electric shock, can see a very strong increase of gill withdrawal reflex, if touch siphon post electric shock the response is much larger than before
mechanism of sensitisation of alpysia
1) L29 neuron responds to the mild electric shock, it synapses with the presynaptic site of the sensory neuron
2) releases 5-HT (serotonin) which is detected by the metabotropic serotonin receptors on the presynaptic buton
3) This activates the G-protein, which in turn activates adenylyl cyclase to convert ATP to cAMP
4) cAMP activates protein kinase A
5) PKA phosphorylates protein targets
6) This inactivates K+ channels, so get a longer depolarisation
7) means get more vesicular release and therefore a greater response
