Deck 16: Synaptic Plasticity

Question 1

Which matches the progressive increase in the amplitude of the postsynaptic potential following a brief train of stimuli applied to the presynaptic nerve?

A) Synaptic facilitation
B) Depression
C) Long-term potentiation
D) Refractory period
E) Long-term depression

Answer 1

A

Question 2

Which describes an increased amplitude postsynaptic response that lasts for milliseconds?

A) Facilitation
B) Depression
C) Post-tetanic potentiation
D) Long-term potentiation
E) Long-term depression

Answer 2

A

Question 3

Which describes an increased amplitude postsynaptic response that lasts for hours?

A) Facilitation
B) Depression
C) Post-tetanic potentiation
D) Long-term potentiation
E) Long-term depression

Answer 3

D

Question 4

Which describes an increased amplitude postsynaptic response that lasts for minutes?

A) Facilitation
B) Depression
C) Post-tetanic potentiation
D) Long-term potentiation
E) Long-term depression

Question 5

Which describes a decreased amplitude postsynaptic response that lasts for hours?

A) Facilitation
B) Depression
C) Post-tetanic potentiation
D) Long-term potentiation
E) Long-term depression

Question 6

What is the difference between post-tetanic potentiation (PTP) and augmentation?

A) PTP lasts for minutes while augmentation lasts only for seconds.
B) Augmentation is an increase in the postsynaptic response amplitude while PTP is a reduced response.
C) Augmentation is a reduction in the postsynaptic response amplitude while PTP is an increased response.
D) PTP relates to current changes while augmentation leads to voltage changes.
E) PTP is a short-term change of synaptic strength while augmentation can last for hours.

Question 7

If the frog neuromuscular junction preparation was bathed in high calcium and curare was used, what type of postsynaptic response would you expect?

A) The response amplitudes would be increased.
B) The response amplitudes would be reduced.
C) The response amplitude would be normal.
D) The responses would occur in a bursting pattern.
E) There would be no response.

Question 8

Which is likely a consequence of increased calcium influx through individual calcium channels?

A) Depression
B) Facilitation
C) PTP
D) LTP
E) LTD

Question 9

Which best describes long-term potentiation?

A) A persistent decrease in synaptic efficacy that lasts hours
B) A persistent increase in synaptic efficacy that lasts seconds
C) A persistent decrease in synaptic efficacy that lasts seconds
D) A persistent increase in synaptic efficacy that lasts hours
E) A change in the number of synaptic vesicles available for release

Question 10

Which stimulus situations would lead to a form of LTP with a decay over 120 minutes and 80% potentiation that persists after two hours?

A) A conditioning train of one pulse
B) A conditioning train of four pulses
C) A conditioning train of eight pulses
D) A single pulse every twenty seconds.
E) A single pulse every two seconds.

Question 11

Which occurs at the first few postnatal days of development?

A) Very few AMPA receptors are found on the postsynaptic element.
B) Very few NMDA receptors are found on the postsynaptic element.
C) Synapses have equal numbers of AMPA and NMDA receptors.
D) No NMDA or AMPA receptors are found.
E) No silent synapses are found.

Question 12

Which is thought to be the result of the activation of silent synapses?

A) Post-tetanic potentiation
B) Long-term depression
C) Inhibitory postsynaptic potentials
D) Postsynaptic expression of LTP
E) Miniature excitatory postsynaptic potentials

Question 13

Synapses following short lasting LTP return to the resting state over time because of

A) constitutive recycling of AMPA receptors into and out of the postsynaptic membrane.
B) addition of AMPA receptors.
C) loss of NMDA receptors.
D) decreased sensitivity of NMDA receptors.
E) decreased probability of glutamate release.

Question 14

What evidence has shown support for presynaptic LTP from recordings of rat hippocampal slice?

A) A decrease in mean current (EPSC) recorded from postsynaptic located electrode following conditioning train of pulses given
B) The mean current of quantum increased following conditioning train of pulses given
C) A decrease in the number of failures following conditioning train of pulses given
D) The mean current of quantum decreased following conditioning train of pulses given
E) No postsynaptic responses recorded following conditioning train of pulses given

Question 15

You complete an experiment with fluorescent dye that binds to lipid membrane of synaptic vesicles. You find synaptic vesicle release is enhanced significantly during LTP. What do you conclude?

A) Postsynaptic mechanism for LTP is supported.
B) The experiment does not support either pre- or postsynaptic mechanism for LTP.
C) Heterosynaptic LTP is supported.
D) Associative LTD is supported.
E) Presynaptic mechanism for LTP is supported

Question 16

What is associated with the third long-lasting component of LTP?

A) It depends on stopping gene transcription.
B) It depends primarily on calcium on calcium entry to soma.
C) There is increased calcium in the postsynaptic area.
D) There is decreased calcium in the presynaptic area.
E) There is increased calcium in the presynaptic area.

Question 17

Eric Kandell showed that repeated tactile stimulation of the siphon or mantle in Aplysia is associated with

A) augmentation at an identified synapse.
B) sensitization at an identified synapse.
C) potentiation at an identified synapse.
D) facilitation at an identified synapse.
E) depression at an identified synapse.

Question 18

In Schaffer collaterals, homosynaptic LTD is blocked by

A) AMPA antagonists.
B) mGluR antagonists.
C) alpha- bungarotoxin.
D) NMDA antagonists.
E) curare.

Question 19

In the cerebellum, homosynaptic LTD is involved with

A) AMPA receptors.
B) NMDA receptors.
C) GABA receptors.
D) mGlu receptors.
E) cholinergic receptors.

Question 20

Parallel fibers in the cerebellum use which type of receptors?

A) mGluR and AMPA R
B) mGluR and NMDA R
C) NMDA only
D) NMDA and AMPA R
E) Glycine

Question 21

Which is generally found in both LTD and LTP?

A) A dependence on NMDA receptors.
B) A dependence on postsynaptic concentration of calcium.
C) A dependence on mGLuR.
D) A dependence on glycine binding.
E) A dependence on GABA binding.

Question 22

Which represents the method of calcium entry in cerebellar Purkinje cells?

A) NMDA R
B) AMPA R
C) Voltage sensitive calcium channels
D) NMDA & AMPA R
E) Ryanodine R

Question 23

Which is involved in LTD expression?

A) An increase in postsynaptic sensitivity to applied glutamate.
B) An increased miniature excitatory postsynaptic potentials.
C) A reduction in postsynaptic sensitivity to applied glutamate.
D) An increased probability of neurotransmitter release.
E) A depletion of synaptic vesicles.

Question 24

How does calcium enter the postsynaptic area in regard to the expression of LTP?

A) Voltage gated calcium channels
B) Calcium leak channels
C) AMPA receptor channels
D) GABA receptor channels
E) Via the NMDA receptor channel

Question 25

Which is needed for NMDA receptor channels to allow calcium to enter?

A) Magnesium must be located in the pore of the channel.
B) The postsynaptic membrane needs to be depolarized.
C) Glutamate needs to be released.
D) Glutamate needs to be released and he postsynaptic membrane needs to be depolarized.
E) Glycine needs to be released.

Question 26

Which scenario would lead to selectively blocking short-lasting LTP?

A) Block of IP₃ receptors
B) Block of ryanodine receptors
C) Block of voltage gated calcium channels
D) Block of voltage gated potassium channels
E) Block of voltage gated sodium channels

Question 27

Which is the location of the ryanodine receptors involved in short lasting LTP?

A) Postsynaptic membrane
B) Presynaptic membrane
C) Endoplasmic reticulum
D) Nucleus
E) Nissl bodies

Question 28

NMDA channels are unusual in that at resting membrane potential they are blocked by

A) gate inactivation.
B) gate closure.
C) magnesium ion blocking the channel from the extracellular side.
D) cesium ion blocking the channel.
E) glycine.

Question 29

Calcium calmodulin-dependent protein kinase II (CaMKII) is necessary for LTP because

A) once activated by calcium, it can auto-phosphorylate and activate itself after calcium concentration lowers.
B) once activated, it leads to the insertion of NMDA receptors to the postsynaptic membrane.
C) once activated, it leads to the removal of AMPA receptors to the postsynaptic membrane.
D) once activated, it leads to gene expression.
E) it is necessary for glutamate binding to the NMDA receptor.

Question 30

Which of the following is preferentially activated at low calcium concentrations?

A) CaMKII
B) Protein phosphatase 2B
C) Calmodulin
D) NMDA receptors
E) Transcriptase

Question 31

The Hebbian rule states that

A) increases in synaptic strength should occur only when the postsynaptic element is repetitively stimulated.
B) increases in synaptic strength should occur when the presynaptic and postsynaptic elements are coactive.
C) decreases in synaptic strength should occur when the presynaptic and postsynaptic elements are coactive.
D) increases in synaptic strength should occur only when the presynaptic element is repetitively stimulated.
E) increases in synaptic strength should occur when the presynaptic and postsynaptic elements are not coactive.

Question 32

Which is not a similarity between spatial learning and LTP?

A) Both are blocked by antagonists of NMDA R.
B) Both are blocked by antagonists of mGlu R.
C) Both are blocked by inhibitors of CaMKII.
D) Both can be enhanced by activation of NMDA R.
E) Both are enhanced if GABA agonists are released.

Question 33

Which is likely involved in aversive (or fear) conditioning?

A) LTP in the amygdala
B) LTP in the cerebellum
C) LTP in the hippocampus
D) LTD in the cerebellum
E) iLTD in the hippocampus

Question 34

Which has been shown to occur when rats trained to associate foot shock with an auditory tone exhibit an exaggerated auditory startle reflex?

A) Cells in the cerebellum show an LTP like increase in their synaptic response.
B) Cells in the amygdala show an LTP like increase in their synaptic response.
C) Cells in the hippocampus show an LTD like increase in their synaptic response.
D) iLTD occurs.
E) Post-tetanic potentiation occurs.

Question 35

Which best describes what has been found with habituation in Aplysia in relation to LTD?

A) Only presynaptic mechanisms are responsible.
B) Only postsynaptic mechanisms are responsible.
C) Only NMDA receptors are involved.
D) Only depletion of synaptic vesicles is involved.
E) Pre- and postsynaptic mechanisms are responsible.

Question 36

Which tends to elicit associative LTP in the hippocampus?

A) A 100 Hz tetanic stimulation applied to electrode site 1 along with a smaller stimulation at a second electrode site 2.
B) A 100 Hz tetanic stimulation applied to electrode site 2 along with a smaller stimulation at a second electrode site 1.
C) A 100 Hz tetanic stimulation is delivered simultaneously at site 1 and II's electrodes together.
D) A 100 Hz tetanic stimulation is delivered one second apart at site 1 and II's electrodes.
E) A 100 Hz tetanic stimulation applied to one electrode site.

Question 37

Which best describes the term used when low frequency pulses delivered at the presynaptic area give rise to a response of depression at that synapse but no other?

A) Homosynaptic LTD
B) Heterosynaptic LTD
C) Associative LTD
D) Cerebellar LTD
E) Presynaptic LTP

Question 38

Which best describes the term used when high frequency pulses delivered at the presynaptic area give rise to a response of potentiation at that synapse but depression at other synapses nearby?

A) Homosynaptic LTD
B) Heterosynaptic LTD
C) Associative LTD
D) Cerebellar LTD
E) Presynaptic LTP

Question 39

Which best describes the term used when coordinated low frequency pulses delivered at two presynaptic areas give rise to depression at one of the synapses, but no response at other synapses nearby?

A) Homosynaptic LTD
B) Heterosynaptic LTD
C) Associative LTD
D) Cerebellar LTD
E) Presynaptic LTP

Question 40

Which does not occur?

A) LTP that is NMDA R dependent in the hippocampus.
B) Long-term changes in transmission at inhibitory synapses.
C) LTD that is NMDA R dependent in the cerebellum.
D) LTP dependent on increase in AMPA R number.
E) LTD dependent on increase in AMPA R number.

Question 41

Which best describes process that modulates GABAergic synapses?

A) LTP
B) Depletion of synaptic vesicles
C) Post-tetanic potentiation
D) Depolarization induced suppression of inhibition (DSI)
E) Augmentation

Question 42

Which best explains depolarization induced suppression of inhibition (DSI) at GABAergic synapses?

A) Activation of NMDA R
B) Activation of cannabinoid receptor
C) Activation of AMPA R
D) Activation of serotoninergic receptor
E) De-activation of NMDA R.

Question 43

The binding of an endocannabinoid receptor on an inhibitory presynaptic terminal leads to a(n)

A) insertion of additional AMPA receptors and increased GABA released.
B) decrease in calcium entry and decreased glutamate released.
C) decrease in calcium entry and decreased GABA released.
D) increased in calcium entry via NMDA R.
E) release of nitrous oxide.

Question 44

Which mediates iLTD?

A) Activation of NMDA R
B) Activation of AMPA R
C) Activation of cannabinoid receptor
D) Activation of serotoninergic receptor
E) De-activation of NMDA R

Question 45

Which process is affected by blockage protein synthesis?

A) Short phases of LTP
B) Post-tetanic potentiation
C) Facilitation
D) Augmentation
E) Induction of iLTD

Question 46

You find that during a train of pulses there is an initial increase in amplitude but there is no increase in amplitude after the second response and later with a test pulse the response is smaller in amplitude. How can you best explain this response?

Question 47

Many studies done on synaptic plasticity are carried out in the frog neuromuscular junction bathed in a low calcium solution. Why?

Question 48

Explain how facilitation and potentiation at a frog neuromuscular junction is generally thought to involve an increased release probability.

Question 49

Devise an experiment to determine if calcium accumulation is involved in facilitation.

Question 50

Describe experimental evidence that supported the idea that increased intracellular calcium acts to modulate calcium channel function.

Question 51

Describe why it is likely that details of the mechanism of short-term plasticity like depression and facilitation may be more variable than already shown.

Question 52

Describe the work of Bliss and Lomo in 1973 at glutamatergic synapse in the hippocampal formation and their major conclusions.

Question 53

Following a high frequency train of pulses delivered at the presynaptic area of
hippocampal cultured cells you find that there is an increase in mean EPSP amplitude and a decrease in synaptic failures compared to control values when no high frequency train of pulses was delivered. What would you conclude in terms of the site of the mechanism for the change?

Question 54

What appears to be the best explanation presently, given what we know, as to why calcium accumulation produces LTP in some circumstances and LTD in other circumstances?

Question 55

Describe the differences in mechanisms between short lasting (hours) and longer
lasting LTP.

Question 56

Describe some of the key advantages to using the hippocampus to study long-term potentiation.

Question 57

Describe an experimental way to examine the role of AMPA receptors play to assisting NMDA receptors. What would you expect to find?

Question 58

Describe how shorter lasting LTP (hours) occurs even when calcium levels decrease in the postsynaptic cell?

Question 59

Describe an experiment that would show the existence of associative LTP.

Question 60

Which of the following areas can undergo iLTD?