Molecular Mechanisms of Learning and Memory Flashcards

Flashcards about the molecular mechanisms of learning and memory.

What is Long Term Potentiation (LTP)?

A long-lasting increase in the response size to single stimulation pulses of the same axons.

Which part of the brain processes faces?

IT (inferior temporal cortex).

What is distributed coding and its benefit in memory?

The population codes for identity, which allows for the identification of a face even if a cell is lost.

Where has most Long Term Potentiation (LTP) work been done in understanding how neurons that fire together, wire together?

The rat hippocampus, specifically the connections from CA3 to CA1 called the Schaffer collaterals.

What is input specificity of LTP?

Only the stimulated inputs are strengthened.

Where are long term memories stored?

Hippocampus, sustained activity, and synaptic strengths.

What does LTP stand for?

Long Term Potentiation.

Which principle explains why memories are robust to brain damage?

Distributed coding.

How do synapses know that two neurons are firing together?

Ca2+ from NMDA channels.

How do NMDA channels detect the co-firing of two neurons?

Presynaptic activity via glutamate binding and Postsynaptic activity via voltage sensitivity.

What two actions do activated kinases perform to make stronger synapse between coactive cells?

Potentiate existing AMPA receptors and trigger insertion of new AMPA receptors.

What role does NMDA receptors plan in representations changing with experience?

NMDA receptors at the synapse detect firing together: Glutamate signals pre-synaptic activity and Mg2+ out of pore signals post-synaptic activity.

What happens when the postsynaptic cell is weakly depolarized in relation to synapses growing weaker?

Weak depolarization allows small amounts of calcium which activates the phosphatases and induces long term depression (LTD).

How does replacing NMDA subunits affect synaptic plasticity?

Replacing NR2B NMDA subunits with NR2A subunits reduces the calcium current and shifts the point where LTP is induced.

In spike timing dependent plasticity, what generates LTP?

Glutamate already bound when the cell depolarizes, allowing greater calcium influx, inducing LTP.