Behavioral activation system (BAS) dysregulation and bipolar spectrum psychopathology in daily life: An online-diary study.

Dysregulation of the behavioral activation system (BAS) has been theorized to be a core factor underlying mood swings in bipolar disorder (BD). However, few studies have directly addressed BAS dysregulation and more research is needed to understand its dynamic expression in daily life. The aim of this study was to directly assess BAS dysregulation, and to examine its moderating effect on the relationship between life events and bipolar spectrum symptoms via multilevel modeling. Korean young adults (n = 100) were screened using the Hypomanic Personality Scale (HPS) from a large sample (N = 1,591). They completed online diaries for 7 consecutive days including the Daily Events Record as well as bipolar spectrum symptoms. BAS-activating and/or -deactivating scores were allocated to each reported life event by an expert consensus rating. Cross-level interaction analysis showed that the occurrence of BA life events contributed to a steeper increase in bipolar spectrum symptoms, particularly for individuals with high BAS dysregulation. The present study suggests that BAS dysregulation is a unique construct that deserves further exploration in BD.