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37. Critical Importance of Exposure Duration for Affective Discrimination of Stimuli that are not Recognised


This study explores the phenomenon of the exposure affect. This is defined as the increase in positive affect that results from the repeated presentation of unfamiliar stimuli.


MethodologyThe subjects of the study were 160 university students between 18-24 years old. The subjects were shown 20 irregular polygons at various lengths of exposure and in various orders. Further trials followed where previously seen stimuli were shown alongside distracter shapes and subjects were asked to select the one they liked best from each pair or the one they had seen before.
ResultsThe experiment was held to show that stimulus exposure duration has different effects on affect and recognition judgements. Affective judgements (do I like it?) can be made after very brief exposures (0-2msec) and are not influenced by extending the exposure time. Recognition judgements require longer exposure (8+msec) and are more directly influenced by length of exposure.
PublishedJournal of Experimental Psychology: Learning Memory and Cognition 10 (3): 465-469
AuthorsSeamon, J.G., Marsh, R.L. and Brody, N.
PublisherAmerican Psychological Association Inc.
Pricesubscription $40
Keywordsvisual perception/ affective discrimination/ phenomenology / cognition

This empirical study sets out to support the Zajonc (1980) theory that affective processing precedes recognition processing. The findings on the effects of exposure duration is highlighted as another independent variable to consider in the design of further research. From this study it would appear that it is a factor which differentially effects affect and recognition performance. This paper argues that affect and recognition are based on different processes.

See also Seamon (1983a) and (1983b)


Seamon, J.G. et al (1983a) Affective Discrimination of stimuli that are not recognised: effects of shadowing, masking, and cerebral laterality Journal of Experimental Psychology: Learning Memory and Cognition 9(3): 544-55.

Seamon, J.G. et al (1983b) Affective Discrimination of stimuli that are not recognised II: effect of delay between study and test. Bulletin of Psychonomic Society 21(3): 187-9.

Zajonc, R.B. (1980) Feeling and Thinking: Preferences need no inferences American Psychologist 35:151-175.