title: Complexities of emotional responses to social and non-social affective stimuli in schizophrenia.
abstract: BACKGROUND
  Adaptive emotional responses are important in interpersonal relationships. We investigated self-reported emotional experience, physiological reactivity, and micro-facial expressivity in relation to the social nature of stimuli in individuals with schizophrenia (SZ).
  
  
  METHODS
  Galvanic skin response (GSR) and facial electromyography (fEMG) were recorded in medicated outpatients with SZ and demographically matched healthy controls (CO) while they viewed social and non-social images from the International Affective Pictures System. Participants rated the valence and arousal, and selected a label for experienced emotions. Symptom severity in the SZ and psychometric schizotypy in CO were assessed.
  
  
  RESULTS
  The two groups did not differ in their labeling of the emotions evoked by the stimuli, but individuals with SZ were more positive in their valence ratings. Although self-reported arousal was similar in both groups, mean GSR was greater in SZ, suggesting differential awareness, or calibration of internal states. Both groups reported social images to be more arousing than non-social images but their physiological responses to non-social vs. social images were different. Self-reported arousal to neutral social images was correlated with positive symptoms in SZ. Negative symptoms in SZ and disorganized schizotypy in CO were associated with reduced mean fEMG. Greater corrugator mean fEMG activity for positive images in SZ indicates valence-incongruent facial expressions.
  
  
  CONCLUSIONS
  The patterns of emotional responses differed between the two groups. While both groups were in broad agreement in self-reported arousal and emotion labels, their mean GSR, and fEMG correlates of emotion diverged in relation to the social nature of the stimuli and clinical measures. Importantly, these results suggest disrupted self awareness of internal states in SZ and underscore the complexities of emotion processing in health and disease.
authors: Department of Psychology, Vanderbilt University, Nashville TN, USA.
authors: Joel S
authors: JS
authors: Peterman
authors: Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville TN, USA.
authors: Esubalew
authors: E
authors: Bekele
authors: Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville TN, USA.
authors: Dayi
authors: D
authors: Bian
authors: Department of Electrical Engineering and Computer Science, Vanderbilt University, Nashville TN, USA ; Department of Mechanical Engineering, Vanderbilt University Nashville, TN, USA.
authors: Nilanjan
authors: N
authors: Sarkar
authors: Department of Psychology, Vanderbilt University, Nashville TN, USA.
authors: Sohee
authors: S
authors: Park
keywords: alexithymia; arousal; electromyogram; negative symptoms; positive symptoms; schizotypal personality; self awareness; valence