Motivational systems and autonomic functioning: Overlapping and differential contributions to anhedonic depression and anxious arousal

This study examined multiple aspects of temperament in order to better understand the distinction and overlap between anxious and depressive symptoms in emerging adulthood. Temperament was measured at the motivational level via self-reported behavioral inhibition (BI) and behavioral activation (BA) and at the physiological level via autonomic functioning [i.e., skin conductance levels (SCL) and respiratory sinus arrhythmia (RSA)]. Emerging adults (N = 170) reported on their BI and BA; SCL and RSA baseline scores were averaged during a 6-min resting period. Results revealed that high RSA was associated with fewer anhedonic depressive symptoms independent of BI and BA, whereas SCL contributed to anhedonic depressive symptoms through a three-way interaction with BI and BA. Specifically, high SCL exacerbated anhedonic depressive symptoms for individuals exhibiting profiles of high BI/low BA and low BI/high BA. This study highlights the importance of examining the unique interactions between psychophysiological and self-report measures of temperament when studying the development of internalizing symptoms in emerging adulthood.