Arousal, Extraversion, and Individual Differences in Resource Availability

Three studies of the effects of extraversion and self-report arousal on attentional task performance were conducted, using sustained attention, visual/memory search, and letter transformation tasks. Differing predictions were derived from the Yerkes-Dodson Law and from Humphreys and Revelle's theory of individual differences in multiple attentional resources. Higher arousal was consistently associated with more efficient performance of demanding versions of the attentional tasks. This finding supports Humphreys and Revelle's hypothesis that arousal is positively associated with the resources required for sustained information transfer. No support for the Yerkes-Dodson Law was found in any study: Relationships between arousal and performance were largely linear. Interactive effects of extraversion and arousal on response criterion were found with self-paced tasks. Extraversion may affect more than 1 type of cognitive process, with the strategic demands of the task influencing the kind of extraversion effect found in any given experiment.