Impulsivity has played a highly variable role in Eysenck's theorizing. In the Eysenck Personality Inventory (EPI), impulsivity and sociability were the two factors whose correlations made up the superfactor of extraversion. However, Imp was correlated not only with high extraversion, but also with high neuroticism. In fact, if E and N were rotated 45 degrees, the new Imp-D dimension was virtually indistinguishable from the lower-level Imp factor. To make things even messier, the finding that Imp is related to psychopathy and antisocial behavior motivated Eysenck to move Imp from E+, N+ in the EPI to E+, P+ in the EPQ; this was done by modifying the item content of the respective scales. Unfortunately, this new Imp is not causally related to diurnal arousal rhythms as is the old Imp. In sum, then, impulsivity illustrates three descriptive aspects of personality research: (a) lower- vs. higher-level factors, (b) unrotated vs. rotated factors, and (c) item content.
Impulsivity could mediate performance on arousal-related tasks in either of two ways. First, impulsivity could be related to rate of change of arousal. If this is the case, then low impulsives should always perform better than high impulsives on arousal-related tasks. Second, impulsivity could be related to diurnal arousal rhythms, with low impulsives becoming alert earlier in the day than high impulsives. If this is the case, then low impulsives should perform better than high impulsives in the morning, but this effect should be reversed in the evening. Which of these alternatives do you think is correct?
Activity: How does Gray's model compare with Eysenck's model? Which is better, and why?