Pupil Response to Threat in Trauma-Exposed Individuals With or Without PTSD

An infrequently studied and potentially promising physiological marker for posttraumatic stress disorder (PTSD) is pupil response. This study tested the hypothesis that pupil responses to threat would be significantly larger in trauma-exposed individuals with PTSD compared to those without PTSD. Eye-tracking technology was used to evaluate pupil response to threatening and neutral images. Recruited for participation were 40 trauma-exposed individuals; 40.0% (n = 16) met diagnostic criteria for PTSD. Individuals with PTSD showed significantly more pupil dilation to threat-relevant stimuli compared to the neutral elements (Cohen's d = 0.76), and to trauma-exposed controls (Cohen's d = 0.75). Pupil dilation significantly accounted for 12% of variability in PTSD after time elapsed since most recent trauma, cumulative violence exposure, and trait anxiety were statistically adjusted. The final logistic regression model was associated with 85% of variability in PTSD status and correctly classified 93.8% of individuals with PTSD and 95.8% of those without. Pupil reactivity showed promise as a physiological marker for PTSD. Resumen Respuesta pupilar a la Amenaza La Respuesta pupilar es un marcador fisiologico para Trastorno por Estres Postraumatico (TEPT) menos frecuentemente estudiado y potencialmente promisorio. Este estudio evaluo la hipotesis de que las respuestas pupilares a la amenaza podrian expresarse diferencialmente en individuos expuestos a trauma con o sin TEPT. Se utilizo tecnologia de seguimiento ocular para evaluar la respuesta pupilar a la amenaza y a imagenes neutrales. Se recluto para participar a 40 individuos expuestos a trauma; 40% cumplia criterios diagnosticos para TEPT. Los individuos con TEPT mostraron significativamente mayor dilatacion pupilar a estimulos relevantes a amenaza comparado a los elementos neutrales (d de Cohen = 0.76) y a los controles expuestos a trauma (d de Cohen = 0.75). La dilatacion pupilar predijo significativamente el 12% de la variabilidad en TEPT luego de considerar el tiempo desde el trauma mas reciente, la exposicion acumulativa a violencia y los rasgos ansiosos. El modelo final de regresion logistica explico el 85% de la variabilidad en el estado de TEPT y clasifico correctamente al 93.8% de los individuos con TEPT y al 95,8% de los controles expuestos a trauma. La reactividad pupilar se muestra promisoria como marcador fisiologico para TEPT. Traditional and Simplified Chinese Abstracts by AsianSTSS ?? : ?????????? ???????????PTSD??? ??: ???????????(PTSD)???????,??????????????????????????????,???PTSD??????????????????????????????????????????40?????????????,?40%??PTSD???????PTSD?????????????,??????(Cohen's d = 0.76)?????????,????????(Cohen's d = 0.75)??,??????????????????????????????????,?????????PTSD?????12%?????????????????PTSD??85%????,??????93.8%?PTSD???95.8%????????????????????PTSD???????? ?? : ?????????? ??????????PTSD??? ??: ???????????(PTSD)???????,?????????????????????????????,???PTSD??????????????????????????????????????????40????????????,?40%??PTSD???????PTSD?????????????,??????(Cohen's d = 0.76)?????????,???????(Cohen's d = 0.75)??,?????????????????????????????????,?????????PTSD?????12%?????????????????PTSD??85%????,??????93.8%?PTSD???95.8%???????????????????PTSD????????