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1. any drug, agent, electrical impulse, or other factor able to cause a response in an organism
2. an object or event that is apprehended by the senses
3. Med a former name for stimulant



something that excites to action and motivates behavior. The concept of stimulus is characteristic primarily of those trends in psychology that base behavior analysis on the stimulus-response correlation (classical psychophysics and especially behaviorism, as well as neobehaviorism). The term “stimulus” is also retained in some psychological concepts that in essence supersede the stimulus-response correlation. Thus, for example, in the Würzburg school, a task or an awareness of a goal is considered to be a stimulus. In this case, the term “stimulus” is almost metaphorical. Even further from the term’s original meaning is the treatment it receives in the cultural and historical conceptions of L. S. Vygotskii, who established a functional difference between stimulus objects, at which action is directed, and stimulus means, by which action is accomplished. According to Vygotskii, signs serve as stimulus means.

In sociopsychological studies a distinction is sometimes made between motives as internal excitations and stimuli as external excitations to action (see Chelovek i ego rabota [collection], 1967, pp. 38–39).



(control systems)
A signal that affects the controlled variable in a control system.
An agent that produces a temporary change in physiological activity in an organism or in any of its parts.
References in periodicals archive ?
Pairing a conditioned stimulus with an unconditioned stimulus is referred to as first-order respondent conditioning.
In humans, practically any unconditioned stimulus can be associated with any conditioned stimulus, and the intensity of the conditioned response usually increases with repeated reinforcement.
The sound of the tuning fork was labeled the conditioned stimulus (CS) since it was dependent upon the unconditioned stimulus.
The researchers also proposed a model that associative learning takes place when a conditioned stimulus is followed by an unconditioned stimulus, triggering convergent neurons.
As is typical of classical conditioning, where the form of the conditioned response tends to replicate that of the unconditioned response to the unconditioned stimulus, the expected increase of ZM activity in the presence of S1 friendly faces and of CS activity in the presence of S1 hostile faces only appeared in those participants who showed the typical pattern of facial responses in the presence of the corresponding expressive faces.
Blocking of inhibitory conditioning within a serial conditioned stimulus-conditioned inhibitor compound: Maintenance of acquired behavior without an unconditioned stimulus.
During conditioning, specimens of Hermissenda are presented with a temporal sequence of a light flash as the conditioned stimulus (CS) and mechanical turbulence as the unconditioned stimulus (US).
On 75% of the CS+ trials, the screen cleared for 2s before the onset of the unconditioned stimulus, which was a loud burst of white noise (80db) of 5s duration delivered to the subject via the headphones.
In the terminology of classical conditioning, the food is called an unconditioned stimulus that reflexively elicits an unconditioned response (i.
In this way, this research intends to establish the net effect of the aversiveness of the prime, regardless of whether its physical form matches that of the unconditioned stimulus in the prior conditioning phase or not.
When a neutral stimulus is presented without consequences and subsequently paired with an Unconditioned Stimulus (US), the Conditioned Response (CR) to the preexposed stimulus is weaker than it is to a novel Conditioned Stimulus (CS) at time of conditioning.