MotorA momentary change or electrical excitation in the voltage difference across the membrane of a neuron that is usually triggered by nerve impulses from a number of other neurons at synapses. It results in an influx of positively charged sodium ions through the cell membrane producing the impulse being propagated along the axon of the neuron. This reverses its resting potential of about -70 millivolts and altering it to about +40 millivolts, thereby increasing the permeability of the membrane to sodium ions and enabling the influx of positively charged ions. In turn, this propagates the potential from the axon hillock down the axon at a speed (or conduction velocity) ranging from about 0.1 to 10 meters per second in fully myelinated axons. Luigi Galvani (1737-1798) was one of the first to demonstrate an action potential through contacting a scapel with the sciatic motor nerve of a frog he was dissecting.
Action potential
See Acetylcholine (AcH), Acetylcholinesterase (AcHE), Action potential, Axon, Axon hillock, Boutons, Climbing fibres, Connectionist models, Denervation, Electromyography (EMG), Gamma aminobutyric acid (GABA), Golgi tendon organ, Motor end plate, Motor unit, Myelin, Neuromuscular junction, Primary visual cortex (V1), Synapse