Vicarious pain responders and emotion: Evidence for distress rather than mimicry.

Up to a third of the population experiences pain when seeing another in pain. The mechanisms underlying such vicarious sensory experiences are thought to reflect hyperactive mirror systems (threshold theory) or dysfunctional processing and representation of oneself versus others (self/other theory). This study investigated whether the tendency to experience vicarious pain corresponds to disinhibited physiological reactivity toward other's emotions, and/or greater empathic mimicry of other's physiological state (respiratory behavior) during fear, pain, and positive emotion. Fifty healthy individuals aged 18-55 years (23 vicarious pain responders) completed empathy- and anxiety-related questionnaires, and a film task. Respiration was measured noninvasively with piezoelectric respiration belts while participants viewed emotional film clips depicting three emotions (fear/pain/positive) interspersed with neutral clips. The emotional stimuli depicted scenes in which the characters showed increases or decreases in respiration. The results suggest that vicarious pain responders do not mimic emotional respiratory behavior. Rather, vicarious pain responders had a significantly slower respiration rate for all emotional stimuli (MDiff  = 1.40 respiratory cycles, SE = .68), compared to nonresponders. However, this was associated with heightened trait anxiety. The findings suggest vicarious pain is associated with acute distress, rather than empathic mimicry of the emotional states of another.