Fibromyalgia patients and controls are equally accurate in detecting tactile stimuli while observing another in pain: an experimental study.

This study investigated the effects of observing pain in others upon vicarious somatosensory experiences and the detection of somatosensory stimuli in both fibromyalgia (FM) patients and controls. The putative modulatory role of dispositional empathy, hypervigilance to pain, and central sensitization was examined. FM patients (n = 39) and controls (n = 38) saw videos depicting pain-related (hands being pricked) and non-pain-related scenes, while occasionally experiencing vibrotactile stimuli themselves on the left, right, or both hands. Participants reported the location at which they felt a somatosensory stimulus. Tactile and visual scenes were presented in the same spatial location (congruent; e.g., left-left) or from opposite locations (incongruent; e.g., left-right). We calculated the proportion of correct responses, vicarious somatosensory experiences (i.e., trials on which an illusory somatosensory experience was reported while observing pain-related scenes), and neglect errors (i.e., reporting only the site congruent to the visual pain-related information when both hands had been stimulated). Observing another in pain resulted in an equal numbers of vicarious somatosensory experiences in both groups and facilitated the detection of tactile stimuli, especially during spatially congruent trials. Counter to our expectations, this facilitation was not moderated by group. FM patients made fewer neglect errors. Hypervigilance for pain, dispositional empathy, and central sensitization did not exert a modulatory role. Observing pain facilitates the detection of tactile stimuli in FM patients and controls. Overall, a low incidence of vicarious experiences was observed. Further research is needed to understand the role of attentional body focus in the elicitation of vicarious experiences.