action potential

noun

: a momentary reversal in electrical potential across a plasma membrane (as of a neuron or muscle fiber) that occurs when a cell has been activated by a stimulus

Examples of action potential in a Sentence

Recent Examples on the Web

For much of the 20th century, neuroscientists believed that neurons performed the heavy lifting of producing conscious experience through a process called spiking, which involves transmitting a signal via an electrical impulse known as an action potential. —Big Think, 20 Aug. 2025

Animals need sodium for neurons to fire action potentials, for proteins to keep their shape and function, and for chemical reactions to occur inside cells — the everyday business of life. —Dan Samorodnitsky, Quanta Magazine, 11 Aug. 2025

Positive ions flow in, causing a voltage change within the neuron that triggers it to fire with an action potential (3) that travels down the axon. —Sangeeta S. Chavan, IEEE Spectrum, 9 June 2025

Excitatory currents prompt one neuron to pass information on to the next through an action potential; inhibitory currents reduce the likelihood that information will be passed on. —New Atlas, 15 Oct. 2024

Word History

First Known Use

1913, in the meaning defined above

Rhymes for action potential

• equipotential
• experiential
• geopotential
• jurisprudential
• nonresidential
• overpotential
• confidential
• differential
• inessential
• inferential
• pestilential
• quintessential

Medical Definition

action potential

noun

: a momentary reversal in the potential difference across a plasma membrane (as of a nerve cell or muscle fiber) that occurs when a cell has been activated by a stimulus

called also spike potential

compare resting potential see afterpotential, generator potential, prepotential