myelin sheath

the insulating layer around many axons that increases the speed of conduction of nerve impulses. It consists of myelin and is laid down by glia, which wrap themselves around adjacent axons. The myelin sheath is interrupted by small gaps, called nodes of Ranvier, which are spaced about every millimeter along the axon. Also called medullary sheath.

Browse dictionary by letter

a b c d e f g h i j k l m n o p q r s t u v w x y z

Psychology term of the day

November 15th 2024

operant behavior

behavior that produces an effect on the environment and whose likelihood of recurrence is influenced by consequences (see operant). Operant behavior is nearly synonymous with voluntary behavior.