Synaptic Strength
The strength of a synapse is defined by the amplitude of the change in membrane potential as a result of a presynaptic action potential. A "synapse" usually refers to a group of connections (or individual synapses) from the presynaptic neuron to the postsynaptic neuron. The strength of a synapse can be accounted for by the number and size of each of the connections from the presynaptic neuron to the postsynaptic neuron. The amplitude of postsynaptic potentials (PSPs) can be as low as 0.4mV to as high as 20mV. The amplitude of a PSP can be modulated by neuromodulators or can change as a result of previous activity. Changes in synaptic strength can be short-term, lasting seconds to minutes, or long-term (long-term potentiation, or LTP), lasting hours. Learning and memory are believed to result from long-term changes in synaptic strength, via a mechanism known as synaptic plasticity.
Read more about this topic: Chemical Synapse
Famous quotes containing the word strength:
“My topic for Army reunions ... this summer: How to prepare for war in time of peace. Not by fortifications, by navies, or by standing armies. But by policies which will add to the happiness and the comfort of all our people and which will tend to the distribution of intelligence [and] wealth equally among all. Our strength is a contented and intelligent community.”
—Rutherford Birchard Hayes (1822–1893)