Neuro (exam 4)

What would happen if Mg2+ was not expelled from NMDA channels?

• Glutamate would not bind to NMDA receptors.

• Glutamate would not bind to AMPA receptors.

• EPSP would not occur.

• LTP would not occur.

What is the mechanism of LTP expression?

• Increase in the number of postsynaptic NMDA receptors

• Increase in the number of postsynaptic AMPA receptors

• Increase in the number of presynaptic AMPA receptors

• Increase in the intracellular level of synaptotagmins

Which mechanism used in hippocampal LTD is not part of the hippocampal LTP mechanism?

• History-dependent modification of synaptic efficacy

• NMDA receptor activation

• Calcium influx

• Calcium-dependent activation of protein phosphatases

Which condition(s) must be met to induce LTP?

• Glutamate must be released from the presynaptic terminal.

• Glutamate must open the postsynaptic AMPA receptors.

• The postsynaptic membrane must be depolarized for a period of time.

• Mg2+ block must be expelled from NMDA receptors to allow Ca2+ influx.

• All of the above

In the context of neuropathological activity, the phenomenon of kindling refers to

• small burns made in cortex by an electrical stimulating electrode.

• the ability to induce LTP in the amygdala and other brain regions in live animals.

• the ability of daily administration of a weak, low-amplitude train of electrical pulses to gradually evoke larger and larger behavioral responses.

• the phenomenon whereby a single, strong electrical pulse can evoke a full-blown seizure.

Glutamate sensitivity (the amplitude of responses to the application of glutamate) is color coded. The micrograph on the right was taken 120 minutes after the micrograph on the left. Which form of plasticity is shown in the figure?

• Habituation

• Sensitization

• LTP

• LTD

Which property of LTP underlies Pavlovian conditioning?

• Requirement for coincident activation of pre- and postsynaptic neurons

• Specificity of input

• Associativity

• Complementarity

What is the immediate consequence of Mg2+ blockade removal from the NMDA receptors?

• Ca²⁺ influx into the presynaptic terminal

• Ca2+ influx into the postsynaptic terminal

• Na+ influx into the postsynaptic terminal

• Glutamate binding to its receptors

What triggers LTD?

• Ca2+ influx into the postsynaptic terminal

• Internalization of AMPA receptors

• High-frequency stimulation

• Low-frequency stimulation followed by small or slow increase in Ca2+

LTP represents a lasting increase in the size of EPSP

• following a high-frequency train of stimuli.

• following a low-frequency train of stimuli.

• following a single stimulus.

• that is restricted to the hippocampus.