temporal summation

a neural mechanism in which an impulse is propagated by two successive postsynaptic potentials (PSPs), neither of which alone is of sufficient intensity to cause a response. The partial depolarization caused by the first PSP continues for a few milliseconds and is able, with the additive effect of the second PSP, to produce an above-threshold depolarization sufficient to elicit an action potential. Compare spatial summation.

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Psychology term of the day

October 15th 2024

cerebellum

n. (pl. cerebella) a portion of the hindbrain dorsal to the rest of the brainstem, to which it is connected by the cerebellar peduncles. The cerebellum modulates muscular contractions to produce smooth, accurately timed ballistic movements; it helps maintain equilibrium by predicting body positions ahead of actual body movements, and it is required for some kinds of motor conditioning. [Latin, literally: “little brain,” diminutive of cerebrum]