classical conditioning

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1. in physical medicine, improvement of physical health by a program of exercises; called also physical conditioning.
2. in psychology, a form of learning in which a response is elicited by a neutral stimulus which previously had been repeatedly presented in conjunction with the stimulus that originally elicited the response. Called also classical or respondent conditioning.

The concept had its beginnings in experimental techniques for the study of reflexes. The traditional procedure is based on the work of Ivan P. Pavlov, a Russian physiologist. In this technique the experimental subject is a dog that is harnessed in a sound-shielded room. The neutral stimulus is the sound of a metronome or bell which occurs each time the dog is presented with food, and the response is the production of saliva by the dog. Eventually the sound of the bell or metronome produces salivation, even though the stimulus that originally elicited the response (the food) is no longer presented.

In the technique just described, the conditioned stimulus is the sound of the bell or metronome, and the conditioned response is the salivation that occurs when the sound is heard. The food, which was the original stimulus to salivation, is the unconditioned stimulus and the salivation that occurred when food was presented is the unconditioned response.

Reinforcement is said to take place when the conditioned stimulus is appropriately followed by the unconditioned stimulus. If the unconditioned stimulus is withheld during a series of trials, the procedure is called extinction because the frequency of the conditioned response will gradually decrease when the stimulus producing the response is no longer present. The process of extinction eventually results in a return of the preconditioning level of behavior.
aversive conditioning learning in which punishment or other unpleasant stimulation is used to associate negative feelings with an undesirable response.
classical conditioning conditioning (def. 2).
instrumental conditioning (operant conditioning) learning in which a particular response is elicited by a stimulus because that response produces desirable consequences (reward). It differs from classical conditioning in that the reinforcement takes place only after the subject performs a specific act that has been previously designated. If no unconditioned stimulus is used to bring about this act, the desired behavior is known as an operant. Once the behavior occurs with regularity the behavior may be called a conditioned response.

The traditional example of instrumental conditioning uses the Skinner box, named after B. F. Skinner, an American behavioral psychologist. The subject, a rat, is kept in the box and becomes conditioned to press a bar by being rewarded with food pellets each time its early random movements caused it to press against the bar.

The principles and techniques related to instrumental conditioning are used clinically in behavior therapy to help patients eliminate undesirable behavior and substitute for it newly learned behavior that is more appropriate and acceptable.
physical conditioning conditioning (def. 1).
respondent conditioning conditioning (def. 2).
work conditioning a physical exercise program designed to restore specific strength, flexibility, and endurance for return to work following injury, disease, or medically imposed rest; it may be part of a complete work hardening program when other aspects of functional restoration are required.

clas·si·cal con·di·tion·ing

a form of learning, as in Pavlov experiments, in which a previously neutral stimulus becomes a conditioned stimulus when presented together with an unconditioned stimulus. Also called stimulus substitution because the new stimulus evokes the response in question.
See also: respondent conditioning.

classical conditioning

n. Psychology
A learning process by which a subject comes to respond in a specific way to a previously neutral stimulus after the subject repeatedly encounters the neutral stimulus together with another stimulus that already elicits the response.

clas·si·cal con·di·tion·ing

(klasi-kăl kŏn-dishŭn-ing)
Form of learning, as in Pavlov experiments, in which a previously neutral stimulus becomes conditioned when presented together with an unconditioned stimulus. Also called stimulus substitution because the new stimulus evokes the response in question.

Classical conditioning

The memory system that links perceptual information to the proper motor response. For example, Ivan Pavlov conditioned a dog to salivate when a bell was rung.
Mentioned in: Amnesia

clas·si·cal con·di·tion·ing

(klasi-kăl kŏn-dishŭn-ing)
A form of learning, as in pavlovian experiments, in which a previously neutral stimulus becomes a conditioned stimulus when presented together with an unconditioned stimulus.
References in periodicals archive ?
Anatomically, the neural circuitry in the amygdala, mainly the basolateral complex, is primarily responsible for associating the conditioned and unconditioned stimuli and the neural circuitry in the hippocampus is primarily responsible for the contextual processing of the stimuli.
This way it was expected to detect all conditioned responses without leaving out any unconditioned stimuli.
In the operant case, although the pairing is between responses and unconditioned stimuli (R-US), the selected relation is also between stimulus and response (s-R; Donahoe, 1994).
Four sessions were carried out at 24-hour intervals with 10 combinations of conditioned and unconditioned stimuli in each session.
All conditioned and unconditioned stimuli were presented to the subject via a Macintosh Power PC computer using the PsyScope (Cohen, MacWhinney, Flatt, & Provost, 1993) experiment generation software.
Short-term memory for 'surprising' versus 'expected' unconditioned stimuli in Pavlovian conditioning.
In one study, Lovibond (1963) demonstrated that electrodermal responses of homosexual males could be conditioned, using film clips of nude males as unconditioned stimuli (USs) and abstract symbols as conditioned stimuli (CSs).
Detection of taste aversions induced by weak unconditioned stimuli like body rotation.
In an attempt to generate even clearer response conflicts with human participants, researchers would do well to consider the strength of the unconditioned stimuli employed.
Drugs can also function as Pavlovian conditional stimuli (CSs), which predict biologically motivating unconditioned stimuli (USs).
Effect of signaling intertrial unconditioned stimuli in autoshaping.
Acquired equivalence learning with antecedent and consequent unconditioned stimuli. Journal of Experimental Psychology: Animal Behavior Processes, 24, 3-14.