The role of distress tolerance in the relationship between frontal alpha asymmetry and mood instability in adolescents

Dysregulation of the Behavioral Approach System (BAS), a neurobiological and psychological system that regulates approach motivation and goal-directed behavior, has been linked to forms of psychopathology, particularly mood disorders. Frontal EEG alpha asymmetry, defined as greater left-than-right frontal alpha band (8-12 Hertz) activity (rLFA), has been used as a neurophysiological marker of the BAS. Although the BAS has been independently linked to both behavioral and emotional dysregulation, examining the interplay of BAS related behaviors and emotions remains less clear, particularly in adolescents. Reduced distress tolerance (DT), a transdiagnostic behavioral marker associated with lower persistence toward goals, may be associated with neurophysiological changes in the BAS. The current study examined the associations among task-induced increase in rLFA, mood instability, and DT in adolescents to examine whether DT is associated with the relationship between BAS-related neural activity and mood instability. Methods Adolescents presenting to a mood disorders clinic ( N =57; M age= 14.77, SD=1.83) completed eyes open resting and a frustrating mirror-tracing task, an indicator of behavioral DT, while EEG data were collected. Results Stable or decreasing rLFA from rest to task was associated with greater DT and less mood instability, whereas resting rLFA alone was not associated with either outcome. An indirect-effect model suggested, at a marginal level, ( p s = .055-.064 when entered simultaneously), that DT was associated with attenuation of the cross-sectional association between rLFA increase and mood instability. Conclusion The study suggests that smaller increase in rLFA during a distress‑producing task is associated with greater behavioral persistence and lower mood instability and highlights DT as an important treatment target in adolescents with behavioral and emotional dysregulation.