The influence of affect on categorization.

Three studies and a pilot experiment showed that positive affect, induced in any of three ways, influenced categorization of either of two types of stimuli—words or colors. As reflected by performance on two types of tasks (rating and sorting), people in whom positive affect had been induced tended to create and use categories more inclusively than did subjects in a control condition. On one task, they tended to group more stimuli together, and on the other task they tended to rate more low-prototypic exemplars of a category as members of the category. These results are interpreted in terms of an influence of affect on cognitive organization or on processes that might influence cognitive organization. It is suggested that borderline effects of negative affect on categorizatio n, obtained in two of the studies, might result from normal people's attempts to cope with negative affect. Recent research has suggested that positive affect may have a pervasive effect on cognitive processes. For example, a mild positive affective state has been shown to be capable of serving as a retrieval cue for positive material in memory, regardless of the affective state the subject was in when the list was learned, influencing such measures as the reaction time for recall of positive words and the subset of words likely to be recalled from a memorized list (e.g., Isen, Shalker, Clark, & Karp, 1978; Laird, Wagener, Halal, & Szegda, 1982; Nasby & Yando, 1982; Teasdale &