Unique association of approach motivation and mania vulnerability.

Bipolar disorder involves experiences of both mania and depression over time, and measures of mania-risk and depression-risk therefore tend to be correlated, making it difficult to disentangle the shared versus unique aspects of mania and depression vulnerability. In theory, strong approach motivation is uniquely linked with mania risk, but this relation tends to be obscured unless co-occurring depression risk is statistically controlled. In this study, 461 college students completed the General Behaviour Inventory (GBI)-a validated questionnaire of bipolar disorder vulnerability-and they reported their degree of approach motivation in response to four vignettes that varied in relative incentive versus threat strength. After controlling for the effect of depression vulnerability, mania vulnerability was associated with approach motivation, particularly in response to more threatening scenarios, and this association remained significant even when controlling for dispositional threat and incentive responsiveness, current symptoms, mood, self-esteem, and optimism. The results are consistent with models that regard heightened approach motivation as a unique aspect of mania vulnerability.