brain plasticity part 2

Question 1

explain hebbs postualte

Answer 1

when 2 cells are active at the same time they become assocaited so that activity in one facilitates activity in the other

(coordinated activity of a presynaptic terminal and post synaptic neuron strengths then connection between them)

Question 2

what are the different forms of short term plasticity

Answer 2

faciilitation
augmentation
potentiation
deperssion

Question 3

explain facilitation in 1 sentence

Answer 3

rapid increase in synaptic strength that occurs when 2 or motor APs invade the presynaptive terminal within milliseconds

Question 4

in facilitation, if you have APs firing closer together in the presynaptic cell, what happens in the post synaptic cell

Answer 4

greater response on post synaptic = more facilitation (increase connection)

Question 5

an the interval between stimuli / AP increases, what happens to the amount of facilitation

Answer 5

decreases

Question 6

explain the reason behind facilitation/mechanism

Answer 6

entry of calcium into the presynaptic occurs fast after AP yet the removal of Ca is slower

=leads to accumulation of calcium, increase in NT release, increase response on post synaptic

Question 7

the fact that entry of calcium into the presynaptic occurs fast after AP and the removal of Ca is slower leads to what

Answer 7

accumulation of calcium in presynaptic, more NT release, more facilitation/response in post synaptic neuron

Question 8

increase in CA will lead to increased or decreased post synaptic activity

Answer 8

increased

Question 9

what is the opposite process to facilitation

Answer 9

depression

Question 10

describe depression in one sentence

Answer 10

sustances synaptic activity causes NT release to decrease because depleting calcium

Question 11

as amount of NT increases, what happens to amount of depression

Answer 11

increases

Question 12

what is the cause of depression

Answer 12

progressive depletion of pool of synaptic vesicles that are available for release

Question 13

when the rate of signal increases, the vesicles deplete faster, what does that do to the strength of tramission

Answer 13

decreases until the pool is regeneratedw

Question 14

where does short term neuropalstic occur

Answer 14

neuromuscular junction (neuron to neurone)

Question 15

what is the time period for short term synaptic palsticn

Answer 15

timescale of tens of mili seconds to a few minutes

Question 16

explain short term synaptic palsticity

Answer 16

affects the amount of NT released from presynaptic terminals in response to AP

(increase AP = increase NT release)

Question 17

what is the cause of short term synaptic plastic

Answer 17

persistent actions of calcium ions within the presynaptic terminal

Question 18

long term potentiation requires the binding of what NT to activate NMDA receptors

Answer 18

glutamate

Question 19

long term potentiation requires the binding glutamate to activate what receptors

Answer 19

NMDA receptors

Question 20

explain what is happening at resting potential in terms of AMPA and NMDA receptors

Answer 20

Glutamate binds to AMPA causing Na to enter the cell (making it more positive, but not enough for depolarization)

mg2 is blocking the NMDA receptor (therefore calcium cannot enter the cell)

Question 21

at resting potential, what is blocking the NMDA recepto

Answer 21

magnums

Question 22

explain what is happening during postsynaptic depolarization in terms of AMPA and NMDA receptors

Answer 22

when there an an increase in stimuli/firing, and there is an AP there is producing in the postsynaptic cell
=magnesium is expelled from the NMDA receptors (calcium can enter)

=leads to LTP

Question 23

NMDA is permeable to BLANK but blocked by magneisuum

Answer 23

calcium

Question 24

NMDA is permeable to calcium but blocked byBLANK

Answer 24

magneisuum

Question 25

NMDA receptor is only active when what

Answer 25

there is an AP that takes place in the post synaptic cell

Question 26

in order to activate the NMDA receptor, what does this require (think Hebbs)

Answer 26

strong coincident presynaptic and post synaptic activity (need a lot of coordinated stimuli from pre synaptic to induce AP in post)

Question 27

in LPT, after many APs are produced in post synaptic cell and there is an increase in calcium in the post synaptic cell, what happens (think membrane)

Answer 27

accumulation of ca leads to increase in membrane trafficking process

calcium will lead to more anchoring of AMPA receptors
=increases chance of more APs since we are increasing the binding sties and allowing more Na to enter)

Question 28

in LTP, when there is an accumulation of calcium in the post synaptic cell, does that lead to an increased or decreased membrane trafficking process

Answer 28

increased

Question 29

what does it mean to have an increased membrane trafficking process

Answer 29

the accumulation of CA will lead to the anchoring of more AMPA receptors

Question 30

true or false, during increased membrane tracking process, the accumulation of CA will lead to the anchoring of more NMDA receptors

Answer 30

FALSE
AMPA RECEOTORS

Question 31

explain late phase LTP

Answer 31

long term there is the activation of a protein kinase which grows a protein

=makes new dendritic spine/synapse location on the post synaptic cell
=increases communication possibility between 2 cells

Question 32

where is LTP

Answer 32

cerebral cortex, cerebellum, amygdala

Question 33

the growing and adapating quality of dendritic spines provide the basis of synaptic plasticity important for what processe

Answer 33

learning and memory

Question 34

what is the general mechanism of LTP

Answer 34

post translational modifications of existing proteins (mostly in changes of trafficking of glutamate receptors/AMPA)

Question 35

what is LTD (quickly)

Answer 35

a low frequency of stimulation causes AMPA receptors on post synaptic to internalize and disappear)

Question 36

short term memory is associated with changes in what

Answer 36

neural firing patterns dn neuromodulator/transmitter release)

Question 37

long term memory is associated with changes in what

Answer 37

assocaited with plastic changes in the brain (numbers nd strength of synapses)