Rethinking emotional reactivity in bipolar disorders: A systematic review and meta-analysis.

Bipolar disorder (BD) has long been associated with changes in emotional reactivity, yet the consistency of this finding remains unclear. We conducted the first systematic review and meta-analysis examining emotional reactivity in BD, comparing individuals diagnosed with, or at high risk for, BD to nonpsychiatric controls or low-risk individuals. The analysis included 112 effect sizes from 35 laboratory studies (1,239 BD/high-risk participants; 1,365 controls), spanning self-reported, behavioral, and psychophysiological measures. Overall, we found no significant difference in emotional reactivity between the BD and non-BD groups (Hedges's g = -0.003, 95% CI [-0.089, 0.083]), but effects were heterogeneous. Moderation analyses of the BD-control contrast found no effects of response channel, valence of emotion induction, BD versus high-risk sample, publication type and year, or study quality indicators. Nonetheless, the type of emotional stimulus and baseline measure mattered; individuals with BD showed less reactivity when responding to standardized emotional images (International Affective Picture System) and to neutral comparison stimuli as opposed to a preinduction baseline measure (note that all studies with International Affective Picture System pictures used neutral comparisons). Additionally, BD participants reported greater decreases in negative emotion in response to positive stimuli compared to controls. We discuss how these findings relate to broader models of emotion in BD, and we note limitations, including the use of laboratory-based stimuli and the predominance of euthymic participants. Our results call for greater attention to the context and methods used when assessing emotion in BD. (PsycInfo Database Record (c) 2025 APA, all rights reserved).