Long-Term Potentiation (LTP)

Question 1

Long-Term Potentiation (LTP)

Answer 1

(Semi-)permanent structural and connectivity changes, via variety of mechanisms

physical change in the circuitry responsible for learning changes

neurological definition of learning

Question 2

Post-Synaptic

P.S.

Answer 2

Include structural changes in Receptor Sites, Dendritization, etc.

Question 3

e.g. Hippocampus in the Rat, in which the best-studied mechanisms of LTP involve…

(P.S.)

Answer 3

• Cells w/multiple types of Glutamate Receptor Sites on the same cell; Some sites harder to trigger than others
• AMPA Receptor Sites
• NMDA Receptor Sites
• Typically Magnesium ions (Mg++) block these gates that, when opened, allow Na+ & Ca++ to enter

Question 4

AMPA Receptor Sites

P.S.

Answer 4

respond well to Glutamate (Ionotroipic: Allow Na+ in to excite Post-Synaptic cell)

Question 5

NMDA Receptor Sites

P.S.

Answer 5

only respond to Glutamate if cell already partially hypo-polarized by above

Question 6

Typically Magnesium ions (Mg++)…

P.S.

Answer 6

….these gates that, when opened, allow Na+ & Ca++ to enter

Question 7

• When Post-Synaptic cell is massively stimulated by Glutamate from multiple Pre-Synaptic cells…

(P.S.)

Answer 7

• AMPA receptors reduce polarity of cell, evict Mg++, allowing NMDA Receptors to also respond

Question 8

• Ca++ influx helps change structure of Post-Synaptic cell, increasing its future responsiveness to Glutamate
  e. g.?

(P.S.)

Answer 8

e. g. New AMPA receptors form, or old ones are made even more responsive
- e.g. Some NMDA Receptors are changed into the easier-to-stimulate AMPA receptors
- e.g. Activates enzymes in cell that break protein “bridges” that structure dendritic spines, splitting them to form new dendritic branches (increased surface area) lined with AMPA Receptors

Question 9

Pre-Synaptic

Answer 9

• Retrograde Messengers (e.g. Nitrous oxide) from Post-Syn cell that prolong NT release
• Perforation

Question 10

Perforation

Answer 10

division, expansion of “Active Zone” of Pre-Syn by out-growth from surface of Post-Synaptic cell

Question 11

Genetic

Answer 11

Activity can turn on transcription of DNA to RNA, then translation of RNA into proteins

• e.g. Such proteins may change #, size, & distribution of NT vesicles, or other relevant metabolic processes in cell

Question 12

Neurogenesis:

Answer 12

Rare in NS overall, but common in Hippocampus, esp re temporal-based and spatial learning

Question 13

Ca++ influx helps change structure of

Answer 13

Post-Synaptic cell, increasing its future responsiveness to Glutamate

Question 14

Retrograde Messengers

Answer 14

released by post-synaptic cell that stimulate pre-synaptic cell, making it easier for connections to form

easier for NT release from pre-synaptic

chemical feedback from post-synaptic cell

Question 15

dendrite increase

Answer 15

their branching

Question 16

terminal buttons

Answer 16

can also multiply