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white matter

parts of the nervous system composed of nerve fibers that are enclosed in a myelin sheath, which gives a white coloration to otherwise grayish neural structures. The sheaths cover only the fibers, so regions containing mainly cell bodies are gray. Compare gray matter.

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Psychology term of the day

December 7th 2024

delayed response

delayed response

a response that occurs some time after its discriminative stimulus has been removed. The most common delayed response task for nonhuman animals is one in which the animal is required to recall the location of a reward after a delay period has elapsed.