High- and low-dose expectancies as mediators of personality dimensions and alcohol involvement.

OBJECTIVE The present study examined the influences of personality dimensions (extraversion, neuroticism) on college alcohol involvement both (1) directly and (2) mediated by positive and negative alcohol expectancies across two imagined (high and low) alcohol doses. METHOD Participants (N = 339; 176 women) were regularly drinking college students who completed a questionnaire battery on demographic characteristics, personality, expectancies, and alcohol use and problems. RESULTS Structural equation modeling analysis of low- and high-dose models revealed partial support for the Social Learning Theory conceptualization of expectancies as mediators of more distal (personality) influences. Interestingly, patterns of association differed by dose. At high-expectancy doses, positive alcohol expectancies fully mediated the extraversion-use association. At low doses, positive expectancies did not play a critical role. Two distinct pathways from neuroticism to alcohol use were observed: a direct pathway, whereby neuroticism is a protective factor for alcohol use, and an indirect pathway, through positive expectancies, whereby neuroticism is a risk factor. The protective pathway was evident regardless of expectancy doses, whereas the risk pathway was evident only at high doses. Negative expectancies partially mediated the association between neuroticism and alcohol problems at both high- and low-expectancy doses. CONCLUSIONS These data underscore the unique role of both positive and negative expectancies in the association between personality and drinking behavior and point to the importance of considering alcohol dose when assessing expectancies. Findings suggest that it may be beliefs about the effects resulting from heavy (rather than moderate) drinking that may be the active mechanism underlying drinking behavior.