node of Ranvier

any of successive regularly spaced gaps in the myelin sheath surrounding an axon. The gaps permit the exchange of ions across the plasma membrane at those points, allowing the nerve impulse to leap from one node to the next in so-called saltatory conduction along the axon. [Louis A. Ranvier (1835–1922), French pathologist]

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Psychology term of the day

December 23rd 2024

delta rule

the principle that the change in strength of an association during learning is a function of the difference between the maximal strength possible and the current strength of the association. The delta rule is used in associationistic learning theory (see associative learning).