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negative discriminative stimulus

(symbol: SΔ or S–) in operant conditioning, a stimulus signifying that a given response will not be reinforced, implying that there is at least one other stimulus circumstance in which the response will be reinforced. Compare discriminative stimulus.

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Psychology term of the day

March 13th 2025

fast muscle fiber

fast muscle fiber

a type of muscle fiber found in skeletal muscle that contracts rapidly but fatigues readily. Compare slow muscle fiber.