Exposure duration as a confounding methodological factor in projective testing.

Exposure duration has been found to have a strong impact on the affective value attributed to a variety of stimuli. The purpose of the study reported here was to examine the impact of this variable in projective testing, and im particular in the affective value subjects attribute to the TAT cards. Using 34 undergraduate students, a linear decrease in pleasantness was found as a function of exposure duration. Factors leading to variation in exposure duration might therefore be confounded with the interpretations made of a subject's protocol. It was suggested that the time a subject views a projective test stimulus should be controlled in the administration.

Effects of "mere exposure" on learning and affect.

The mediating role of learning in the relationship between repeated exposure and affect was explored and supported in three experiments involving a total of 229 undergraduate participants. It was found that both learning and affect measures behaved in essentially the same way as a function of exposure duration (Experiments 1 and 3), serial position (Experiments 1 and 2), rating delay (Experiment 1) and stimulus properties (Experiment 1). These results suggest learning may be intrinsically rewarding and clarify one of the mechanisms involved in the relationship between exposure frequency and affect, extending Berlyne's two-factor theory of the effects of stimulus familiarity.