Beyond Main Effects? Affect Level as a Moderator in the Relation Between Affect Dynamics and Depressive Symptoms

The current study examined the role of mean levels of affect in the relation between affect dynamics and depressive symptoms. We analyzed data from seven studies that measured affect in daily life in adolescents and young adults (N = 1,448, age range = 11.7-29.9 years, 64.8% females). We tested main and interaction effects of affect dynamics (variability and inertia) and affect level on depressive symptoms, separately for positive affect (PA) and negative affect (NA). For PA, we found mostly main, but no interaction effects. Depressive symptoms were associated with more PA variability and less PA inertia, indicating that depressive symptoms in young people may be characterized by more variable and less lingering PA, independent of PA mean levels. For NA, we found a significant moderation effect between NA variability and NA levels for depressive symptoms at baseline. For individuals with low NA levels, high NA variability was associated with more depressive symptoms. In contrast, for individuals with high NA levels, high NA variability was associated with fewer depressive symptoms. These results suggest that the relative adaptiveness of NA variability depends on overall NA levels and underscores the need for a more nuanced understanding of affect variability in depression.