Emotion

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Emotion, term frequently and familiarly used as synonymous with feeling. In psychology it signifies a reaction involving certain physiological changes, such as an accelerated or retarded pulse rate, the diminished or increased activities of certain glands, or a change in body temperature, which stimulate the individual, or some component part of his or her body, to further activity. The three primary reactions of this type are anger, love, and fear, which occur either as an immediate response to external stimuli or are the result of an indirect subjective process, such as memory, association, or introspection.

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