Effects of single and repeated shock on perceived pain and startle response in healthy volunteers

Video-Based Analysis of Bodily Startle and Subsequent Emotional Facial Expression in Posttraumatic Stress Disorder

Exaggerated startle is a core hyperarousal symptom of Posttraumatic Stress Disorder (PTSD). Observational studies on the characteristics of this response are strikingly lacking. Previous research has demonstrated that detailed video analysis of facial and bodily responses to startling stimuli enables the differentiation of an initial, primarily reflexive response and a secondary, primary emotional response. We exposed PTSD patients (n = 34) and trauma-exposed but healthy participants (TE group, n = 26) to startling electric stimuli while acquiring observational behavioral, psychophysiological, and experiential measures. Videographic results indicate that PTSD patients' initial bodily startle response was stronger than in the TE group, and their secondary facial expression was more negatively valenced, largely due to elevated anger expression. Videographic assessment of primary and secondary startle responses provides a new window into reflexive and emotional functioning of PTSD and may therefore complement existing startle measures. PTSD treatments should address bodily startle, negative symptom appraisals, and anger more specifically.