habituation

1. The process of forming a habit, referring generally to psychological dependence on the continued use of a drug to maintain a sense of well-being, which can result in drug addiction. 2. The method by which the nervous system reduces or inhibits responsiveness during repeated stimulation.

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ha·bit·u·a·tion -.bich-ə-'wā-shən n

1) the act or process of making habitual or accustomed

2 a) tolerance to the effects of a drug acquired through continued use

b) psychological dependence on a drug after a period of use compare ADDICTION

3) a form of nonassociative learning characterized by a decrease in responsiveness upon repeated exposure to a stimulus compare SENSITIZATION (3)

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n.

1. (in psychology) a simple type of learning consisting of a gradual waning response by the subject to a continuous or repeated stimulus that is not associated with reinforcement.

2. (in pharmacology) the condition of being psychologically dependent on a drug, following repeated consumption, marked by reduced sensitivity to its effects and a craving for the drug if it is withdrawn. See also dependence.

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ha·bit·u·a·tion (hə-bich″u-aґshən) 1. the gradual adaptation to a stimulus or to the environment. 2. extinction or decrease of a conditioned reflex over time by repetition of the conditioned stimulus. 3. an older term used in describing habitual drug use, used sometimes to denote drug tolerance (see under tolerance) and other times to denote psychological but not physical dependence on a drug as a consequence of repeated consumption, with a desire to continue its use but with little or no tendency to increase the dose.