Question

How synaptic plasticity works on learning&memory?

Answer 1

Synaptic plasticity means increase in response with repeated activity. it is most commonly seen in the hippocampus region which is concerned with memory. Hippocampus converts short term memory into long term memory with a phenomenon called synaptic plasticity. Synaptic plasticity is also known as post tetanic potentiation/ long term potentiation.

In synaptic plasticity, the hippocampus has two pathways:- direct and indirect. In the direct pathway, entorhinal cortex is stimulated which directly stimulates the CA1 neurons. In the indirect pathway, entorhinal cortex is stimulated which further stimulates dentate nucleus and CA3 neurons which in turn stimulate the CA1 neurones. With the repeated activity, glutamate is released as a neurotransmitter through CA1 neurons. This glutamate acts on the postsynaptic membrane and stimulates NMDA receptors. These receptors causes calcium influx which acts as a second messenger and stimulates the protein synthesis. These proteins act on the synapse and provide strength to it. In this way, short term memory, with repeated revision, is converted into long term memory by synaptic plasticity.