action potential


Definition of action potential

: 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 This was noteworthy because conventional action potentials are usually caused by sodium and potassium ions. Quanta Magazine, "Hidden Computational Power Found in the Arms of Neurons," 14 Jan. 2020 Neurons firing action potentials that affect the downstream cells they are wired to (via synapses) are one type of mechanism, as are electronic circuits, made of transistors, capacitances, resistances and wires. Christof Koch, Scientific American, "Will Machines Ever Become Conscious?," 1 Dec. 2019 Divide and Conquer The brain is a power-hungry organ; neurons are constantly sending each other information in the form of electrical pulses, known as spikes or action potentials. Quanta Magazine, "The Neuroscience Behind Bad Decisions," 23 Aug. 2016

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'action potential.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of action potential

1913, in the meaning defined above

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Time Traveler for action potential

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The first known use of action potential was in 1913

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Cite this Entry

“Action potential.” Dictionary, Merriam-Webster, Accessed 14 Aug. 2020.

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More Definitions for action potential

action potential


Medical Definition of action potential

: 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

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