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threshold effect

an effect in a dependent variable that does not occur until a certain level, or threshold, is reached in an independent variable. For example, a drug may have no effect at all until a certain dosage level (the threshold value) is reached. The change in the dependent variable can be an irreversible dichotomous change (e.g., from functional to not functional), or it can be continuous, such that the dependent variable changes each time the independent variable crosses the threshold in either direction.

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Psychology term of the day

October 5th 2024

identity theory

identity theory

the theory that mental states are identical with brain states. In token identity theory, identical mental and brain states occur within the individual. Type identity theory extends this to theorize that when two or more people share a mental state (e.g., the belief that ice is cold) they also have the same brain state. Also called central state theory; identity theory of the mind. See also eliminativism; epiphenomenalism; materialism; mind–body problem; physicalism; reductionism.