In neuroscience, a silent synapse is an excitatory glutamatergic synapse whose postsynaptic membrane contains NMDA-type glutamate receptors but no AMPA-type glutamate receptors. These synapses are named "silent" because normal AMPA receptor-mediated signaling is not present, rendering the synapse inactive under typical conditions. Silent synapses are typically considered to be immature glutamatergic synapses. As the brain matures, the relative number of silent synapses decreases. However, recent research on hippocampal silent synapses shows that while they may indeed be a developmental landmark in the formation of a synapse, that synapses can be made silent by activity, even once they have acquired AMPA receptors. Thus, silence may be a state that synapses can visit many times during their lifetimes.
Read more about Silent Synapse: Synaptic Transmission, Characteristics, Activation, Controversy
Famous quotes containing the word silent:
“A puff of wind, a puff faint and tepid and laden with strange odours of blossoms, of aromatic wood, comes out the still night—the first sigh of the East on my face. That I can never forget. It was impalpable and enslaving, like a charm, like a whispered promise of mysterious delight.... The mysterious East faced me, perfumed like a flower, silent like death, dark like a grave.”
—Joseph Conrad (1857–1924)