Also found in: Medical.
a large and sudden change in electrical potential that accompanies excitation in nerve and muscle cells and fibers. In physiology, the term “spike potential” is often used as a synonym for action potential. In clinical electroencephalography spike potential refers to gross potentials reaching 10 milliseconds in duration that are outwardly similar to the action potential of a nerve. These potentials are detected in an electrocorticogram taken with certain pathological disturbances, particularly epilepsy.