|a localized change in electrical potential, from about --70 mV to +30 mV and back again, that occurs across a nerve fibre during transmission of a nerve impulse|
action potential n.
The change in membrane potential occurring in nerve, muscle, or other excitable tissue when excitation occurs.
The rapid change in electric potential that parts of a nerve cell undergo when a nerve impulse is generated. Unlike ordinary electric current, which consists of the flow of electrons, the action potential involves the movement of sodium and potassium ions across the cell membrane.