Does the Electrodermal System "Take Sides" When It Comes to Emotions?

Traditionally, electrodermal research measurements were taken from the non-dominant hand. This was considered a valid measurement of arousal for the whole body. Some, however argue for a complex and asynchronous electrodermal system in terms of lateral and dermatome differences in emotional responding. The present study measured skin conductance responses to emotionally laden musical stimuli from the left and right index and middle fingers, as well as the left and right plantar surface of right handed participants (N = 39). The 7-s musical segments conveyed four emotional categories: fear, sadness, happiness and peacefulness. Our results suggest, that the electrodermal system responds to emotional musical stimuli in a lateralized manner on the palmar surfaces. Fear, sadness and peacefulness prompted right hand dominance while happiness elicited left hand dominant response. Lateralization of the palmar and plantar surfaces differed significantly. Moreover, an association between lateralization of the electrodermal system in response to fear and state anxiety was found. Results of the present study suggest that the electrodermal system displays lateral preferences, reacting with varying degree of intensity to different emotions. Apart from lateral differences, music induced emotions show dermatome differences as well. These findings fit well with Multiple Arousal Theory, and prompt for revaluating the notion of uniform electrodermal arousal.