stimulus

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stimulus

 [stim´u-lus] (L.)
any agent, act, or influence that produces functional or trophic reaction in a receptor or an irritable tissue.
conditioned stimulus a stimulus that acquires the ability to evoke a given response by repeatedly being linked with another stimulus that naturally evokes that response; see also conditioning.
depolarizing stimulus a stimulus that lowers the resting potential, making the inside of a fiber less negative. In cardiac fibers this means bringing the resting potential from −90 mV to −70 mV.
discriminative stimulus a stimulus associated with reinforcement, which exerts control over a given type of behavior; the subject must discriminate between closely related stimuli and respond positively only with this particular stimulus.
eliciting stimulus any stimulus, conditioned or unconditioned, that elicits a response.
threshold stimulus a stimulus that is just strong enough to elicit a response.
unconditioned stimulus any stimulus that naturally evokes a specific response; see also conditioning.

stim·u·lus

, pl.

stim·u·li

(stim'yū-lŭs, -lī),
1. A stimulant.
2. That which can elicit or evoke action (response) in a muscle, nerve, gland or other excitable tissue, or cause an augmenting action upon any function or metabolic process.
[L. a goad]

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.
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.

stimulus

(stĭm′yə-ləs)
n. pl. stimu·li (-lī′)
1. Something causing or regarded as causing a response.
2. An agent, action, or condition that elicits or accelerates a physiological or psychological activity or response.

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.

stim·u·lus

, pl. stimuli (stim'yū-lŭs, -lī)
1. A stimulant.
2. That which can elicit or evoke action (response) in a muscle, nerve, gland or other excitable tissue, or cause an augmenting action on any function or metabolic process.
[L. a goad]

stimulus

Anything that causes a response, either in an excitable tissue or in an organism.

stimulus

any detectable change in the environment (internal or external) of an organism which is capable of activating a receptor and thus producing a RESPONSE in the whole organism or parts of it.

Stimulus

A factor capable of eliciting a response in a nerve.
Mentioned in: Pain, Pain Management

stimulus

that which evokes a reaction in excitable tissues

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.

stim·u·lus

, pl. stimuli (stim'yū-lŭs, -lī)
That which can elicit or evoke action (response) in a muscle, nerve, gland or other excitable tissue, or cause augmenting action on any function or metabolic process.
[L. a goad]

stimulus (stim´ūlus),

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

stimulus

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

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.
References in periodicals archive ?
Since we postulated premier expression as the initial emotional output, it was necessary to conducted a detailed checking on how the muscle activities changed during the first 300ms after stimuli onset.
Nonapplied stimulus equivalence procedures commonly utilize only abstract stimuli that are assumed to be unfamiliar to the participant prior the stimulus equivalence experiment.
The multiple-stimulus (MS) and multiple-stimulus without replacement (MSWO) assessment procedures require students to select one of many stimuli presented in an array (Hagopian et al.
The present data provide clear evidence of a perceptual learning effect on a same-different test, using a novel procedure involving tactile stimuli differing in roughness.
Recently, using stimuli varying in brightness contrast, some neuroimaging studies have also shown that there is a close correlation between fMRI or magnetoencephalography signals in primary visual cortex (V1) and the perceived contrast of stimuli (Haynes, Roth, Stadler, & Heinze, 2003; Williams, Singh, & Smith, 2003).
The relative arrangement of previously reinforced and previously non-reinforced stimuli was varied in quasi-random fashion (in 8 successive presentations, 4 times on the left and 4 times on the right; no more than twice in succession on either side).
The possibility of a modality weakness for certain stimuli was tested in a subsequent study.
Thus, the emergence of relations between stimuli may occur in the absence of a history of reinforced responding with respect to stimulus pairs of the same class, and without the aid of previously acquired verbal substitutes for the stimuli involved.
The experimental millipedes received the vibrational stimuli repeatedly to test for habituation, while the control millipedes only received two vibrational stimuli separated by a 78 minute time interval.
Children with disabilities often have difficulty attending and discriminating among the relevant properties of stimuli to master both basic and generalized matching.