sleep–wake cycle

the natural, brain-controlled bodily rhythm that results in alternate periods of sleep and wakefulness. The sleep–wake cycle may be disrupted by a number of factors, such as flight across time zones, shift work, drug use, or stress (see circadian rhythm sleep disorder; disorders of the sleep–wake cycle schedule). Also called sleep rhythm; sleep–wakefulness cycle. See also monophasic sleep; polyphasic sleep.

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Psychology term of the day

January 23rd 2025

intrinsic activity

intrinsic activity

1. the magnitude of a response to a drug regardless of dosage.

2. a measure of the efficacy of a drug-receptor complex in producing a pharmacological effect. Also called intrinsic efficacy.

3. the inborn readiness of babies to be inquisitive and to make contact with their environment. According to Jean Piaget, cognitive structures, by their very nature, seek to be active, predisposing the child to learn from experience with the environment.