Neuroplasticity and Memory

Question 1

Activity dependent competition

Answer 1

Immature muscle has polyneuronal innervation…as you mature, a single motor axon will innervate a single muscle fiber…coordination

If there is receptor blocked, terminal will recede

Question 2

Ocular dominance columns

Answer 2

Example of activity depdentent competiont

Question 3

Crtical period of ocular dominance columns

Answer 3

Once critcial period has passed, losing one eye will not affec the ocular dominance columns

Question 4

Trisynaptic pathway

Answer 4

Entorhinal cortex to dentate gyrus granule cells via perfornat pathwya

Granule cells to CA3 via mossy fibers

CA3 to CA1 via schaeffer collaterals

CA to subiculum

Subiculum to mammillary bodies via fornix or directyl to entorhinal cortex

Question 5

Adult neurogenesis

Answer 5

After seizure, may grow back in a way that will have bad connections

Question 6

Post-injury axon sprouting

Answer 6

Axons will synapse on other granule cells…this is not good

Question 7

Synaptic reorgnization

Answer 7

After fiber sprouting, stimulus will have longer depolarization and increase # of APs

Question 8

Removal of hippocampus

Answer 8

Anterograde amnesia

Question 9

LTP process

Answer 9

Early lasts quick, but with more trains, late LTP will last much longer

Question 10

Physiologic LTP

Answer 10

High frequency stimulus causes Ca to flow through NMDA channel…uses kinase to phosphorylate non-NMDA receptors to givbe postsynaptic maintencne

Presynpatic maintencne from retrograde messengers

Question 11

With repeated trains

Answer 11

Ca influx recruits adenylyl cyclase which activates cAMP…can lead to new synapse formation, dnedrite growht or AMPA receptor traffic to membrane

Question 12

LTD

Answer 12

Long term depression

Low frequnecy stimulation and phosphatase dependent