conditioned

Conditioned is the past participle of condition and can describe something that has been shaped, prepared, or influenced by a conditioning process. In everyday language it often refers to states, responses, or systems that have been learned or deliberately arranged to meet certain standards. In psychology, conditioning refers to learning that links stimuli or behaviors with outcomes.

Classical conditioning, formulated by Ivan Pavlov, pairs a neutral stimulus with an unconditioned stimulus so that the neutral stimulus becomes capable of eliciting a conditioned response. Features of this process include acquisition, extinction, spontaneous recovery, generalization, and discrimination; higher-order conditioning is also possible.

Operant conditioning, associated with B. F. Skinner, focuses on how behaviors are influenced by their consequences. Behaviors followed by reinforcement are more likely to recur, while those followed by punishment are less likely. Reinforcement can be studied on various schedules and through shaping, where complex behaviors are built up from simpler steps.

Beyond psychology, conditioned is used in other domains. In everyday language, a room or building may be described as air-conditioned. In medicine and research contexts, conditioning can refer to preparatory procedures, such as conditioning regimens before transplantation, or to treatments designed to prepare tissues or systems for a particular outcome.

In learning science, conditioned responses are contrasted with unconditioned responses, and the study of conditioning encompasses processes such as extinction, spontaneous recovery, blocking, and generalization to understand how associations form and change. See also conditioning, reflex, reinforcement, Pavlov, Skinner.