1g. Synaptic Plasticity

Question 1

Short Term Excitability Changes

- Stages

Answer 1

1. Facilitation
2. Depression
3. Post-tetanic potentiation

Question 2

Short Term Excitability Changes

- Facilitation

Answer 2

EPSP increases with tetanic stimulation due to Ca2+ accumulation which increases Ca2+ vesicle release

Question 3

Short Term Excitability Changes

- Depression

Answer 3

EPSP decreases with further tetanic stimulation due to depletion of the readily releasable vesicle pool

Question 4

Short Term Excitability Changes

- Post-Titanic Potentiation

Answer 4

After cessation of the tetanic stimulus and once the synapse has recovered from depression, administration os a single stimulus gives an EPSP much higher than the initial EPSP.
This is due to an increase in the releasable vesicle pool

Question 5

Long Term Excitability Changes

- 2 Types

Answer 5

• Long term potentiation (LTP)

- Long term depression (LTD)

Question 6

Long Term Potentiation

- Area of the brain

Answer 6

Area CA1 of the hippocampus

Question 7

Hebb’s Law

Answer 7

“When an axon of cell A is near enough to excite cell B, or repeatedly or consistently takes part in firing it, some growth process or metabolic change takes place in one or both cells such that A’s efficiency, as one of the cells firing B, is increased”

An input is strengthened when it plays a role in firing the target cell, which is what is required for learning.