IMPULSIVITY, NEUROTICISM, AND CAFFEINE - DO THEY HAVE ADDITIVE EFFECTS ON AROUSAL

The personality dimensions of impulsivity and neuroticism have been linked to differences in basal arousal. The hypothesis tested was whether these personality variables and caffeine have additive effects on arousal. All subjects received three paired-associate trials on each of two neutral control lists, two lists with semantically similar stimuli, and two lists with acoustically similar stimuli. Half of the subjects received caffeine and half placebo. Although significant interactions with personality and drug condition were obtained, the ordering of the conditions was inconsistent with the assumption that the arousal performance curve is single peaked. Further, S. Schwartz's (Journal of Research in Personality, 1975, 9, 217-225) hypothesis that in paired-associate learning high arousal and low arousal subjects process semantic and physical information differentially was not supported. The general issue of how to determine whether individual differences in performance are caused by differences in arousal is discussed. © 1979.