The synchronization of electrodermal activity and heart rate and its relationship to energetic arousal: a time series approach.

We examined the synchronization between indices of autonomic nervous system (ANS) function and its relation to multiple measures of arousal in 37 middle-aged men. Electrodermal activity (EDA), heart rate (HR), and subjective and behavioral arousal were measured during administration of the Rorschach test. Prevailing mood and depression were also measured. The relationship between phasic EDA and HR activity was assessed by constructing within-subjects time series models. The results showed that phasic EDA and HR accelerations were synchronized, while there was no association between tonic EDA and HR in between-subjects analysis. In addition, EDA-HR synchronization was positively associated with verbal activity, variability of arousal experience, and activation mood, and negatively associated with depression. It is suggested that within-subjects analysis of physiological time series data can further our understanding of the individual differences in ANS function and on the correlates of effector organ synchronization.