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Related to unconditioned stimulus: classical conditioning, operant conditioning, unconditioned response, stimulus generalization
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.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
a stimulus that elicits an unconditioned response; for example, food is an unconditioned stimulus for salivation, which in turn is an unconditioned response in a hungry animal. See: classical conditioning.
Farlex Partner Medical Dictionary © Farlex 2012
A stimulus that evokes an unconditioned response.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.
un·con·di·tioned stim·u·lus(ŭn'kŏn-dish'ŭnd stim'yū-lŭs)
That which elicits an unconditioned response; e.g., food is an unconditioned stimulus for salivation, which in turn is an unconditioned response in a hungry animal.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
unconditioned stimulusThe stimulus that evokes an UNCONDITIONED RESPONSE.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005