16. Cellular Learning and Memory

Question 1

Learning

Answer 1

Process which experiences change our brain and therefore our behavior

Question 2

Memories

Answer 2

Changes of learning, not constantly maintained

Question 3

Retrieval

Answer 3

Accessing memories

Question 4

Neuronal plasticity

Answer 4

Ability of neurons to change and adapt

Question 5

Intrinsic excitability of neurons

Answer 5

Number of action potentials exhibit when cell membrane is depolarized a set among, measured by brain slicing recording

Question 6

Synaptic strength

Answer 6

How large the post synaptic response is when a presynaptic neuron has an action potential

Question 7

Synaptic plasticity

Answer 7

Change in synaptic strength

Question 8

What does repeated touches to Aplysia’s siphon do to their gill?

Answer 8

Touches become ignored - example of habituation

Question 9

Habituation and what happens between the connection in Aplysia?

Answer 9

Reduced phsyiological or behavioral response

Connection between sensory and motor neurons weakens

Question 10

Sensitization

Answer 10

Exposure to strong stimulus results in heightened responses to other stimuli

E.g., in Aplysia they will be more sensitive to their gill being touched

Question 11

Long-term Potentiation (LTP)

Answer 11

Enduring increase in strength of connection between two neurons

Releases signaling molecules associated with nitric oxide to trigger change on presynaptic side (starts on postsynaptic side)

Question 12

Long-term depression (LTD)

Answer 12

Enduring decrease in strength of connection between two neurons

Releases signaling molecules associated with endocannabinoids to trigger changes on presynaptic side (starts on postsynaptic side)

Question 13

What frequency of stimulation of afferent glutamate produces LTP?

Answer 13

High frequency

Question 14

What frequency of stimulation of afferent glutamate produces LTD?

Answer 14

Same as LTP (high frequency) but at a slower rate

Question 15

What coincides during LTP?

Answer 15

Release of neurotransmitter with depolarization of postsynaptic cell

Why high frequency stimulation typically causes LTP, because it neurons tend to spike in response to stimulation

Question 16

Why does low frequency stimulation produce LTD?

Answer 16

Low frequency is insufficient to get postsynaptic neurons to spike (aka opposite of LTP)

Question 17

What are the two types of glutamate receptors?

Answer 17

AMPA and NMDA (both are ionotropic and permeable to Na+)

Question 18

AMPA

Answer 18

Glutamate receptor that lets Na+ in when bound to glutamate -> membrane depolarizes

Question 19

NMDA

Answer 19

Glutmate receptor permeable to Na+ and Ca2+, does not consisitently cause membrane depolarization

Question 20

What happens to NMDA when the membrane potential is more negative than -40 mV?

Answer 20

Pores of NMDA gets clogged by magnesium

Question 21

What happens to NMDA when the membrane potential is less negative than -40 mV?

Answer 21

Magnesium ion does not clog and Na+ and Ca2+ flow in

Question 22

What does the strength of synapse of glutamate equate to?

Answer 22

The number of AMPA receptors since they let Na+ -> depolarize membrane

Question 23

CaMKII

Answer 23

Type of II calcium-calmodulin kinase that increases the number of AMPA when activated, responsible for long-term increases in LTP

Question 24

Donald Hebb’s hypothesis

Answer 24

Classical Conditioning - cellular basis of learning involving strengthening of weak synaptic connections

“Neurons that fire together, wire together”

Question 25

What causes weak pathways to become stronger?

Answer 25

Simultaneous stimulation of weak and strong pathways