stimulus

stimulus /stim·u·lus/ (stim´u-lus) pl. stim´uli   [L.] any agent, act, or influence which produces functional or trophic reaction in a receptor or an irritable tissue.

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adequate stimulus  a stimulus of the specific form of energy to which a given receptor is sensitive.

aversive stimulus  one which, when applied following the occurrence of a response, decreases the strength of that response on later occurrences.

conditioned stimulus  a stimulus that acquires the capacity to evoke a particular response on repeated pairing with another stimulus naturally capable of eliciting the response.

discriminative stimulus  a stimulus, associated with reinforcement, that exerts control over a particular form of behavior; the subject discriminates between closely related stimuli and responds positively only in the presence of that stimulus.

eliciting stimulus  any stimulus, conditioned or unconditioned, that elicits a response.

heterologous stimulus  one that produces an effect or sensation when applied to any part of a nerve tract.

homologous stimulus  adequate s.

threshold stimulus  a stimulus that is just strong enough to elicit a response.

unconditioned stimulus  any stimulus naturally capable of eliciting a specific response.

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stim·u·lus (stmy-ls)

n. pl. stim·u·li (-l)

1. A stimulant.

2. That which can elicit or evoke an action or response in a cell, an excitable tissue, or an organism.

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Stimulus

A factor capable of eliciting a response in a nerve.

Mentioned in: Pain, Pain Management

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stimulus

[stim′yələs] pl. stimuli

Etymology: L, stimulare, to incite

anything that excites or incites an organism or part to function, become active, or respond. stimulate, v.

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stimulus (stim´ūlus),

n a chemical, thermal, electrical, or mechanical influence that changes the normal environment of irritable tissue and creates an impulse.

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stimulus

pl. stimuli [L.] any agent, act, or influence that produces functional or trophic reaction in a receptor or an irritable tissue.

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conditioned stimulus

a neutral object or event that is psychologically related to a naturally stimulating object or event and which causes a conditioned response. See also conditioning.

discriminative stimulus

a stimulus associated with reinforcement, which exerts control over a particular form of behavior; the subject discriminates between closely related stimuli and responds positively only in the presence of that stimulus.

eliciting stimulus

any stimulus, conditioned or unconditioned, which elicits a response.

stimulus generalization

in learning by animals stimuli tend to be grouped together, the reactions lacking the discrimination of the higher mammals.

stimulus response coupling

coupling of the neural or endocrine stimulus to the cellular response.

structured stimulus

a well-organized and unambiguous stimulus, the perception of which is influenced to a greater extent by the characteristics of the stimulus than by those of the perceiver.

threshold stimulus

a stimulus that is just strong enough to elicit a response.

unconditioned stimulus

any stimulus that is capable of eliciting an unconditioned response. See also conditioning.

unstructured stimulus

an unclear or ambiguous stimulus, the perception of which is influenced to a greater extent by the characteristics of the perceiver than by those of the stimulus.

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stimulus 

Any agent or environmental change that provokes a response. Plural: stimuli. See action potential.
adequate stimulus A stimulus of sufficient intensity and of appropriate nature to provoke a response in a given receptor. Visible light is the adequate stimulus for the eye, but pressure on the eye that may nevertheless produce a response (called a phosphene) is an inadequate stimulus.
inadequate stimulus  See adequate stimulus.
liminal stimulus A stimulus of an intensity such that it just provokes a response that is at threshold. Syn. threshold stimulus.
threshold stimulus See liminal stimulus.