Eye Tracking and Visual Attention to Traumatic Stimuli in Veterans of the Iraq War

Eye tracking and physiological reactivity to threatening stimuli in posttraumatic stress disorder

“…This effect was not influenced by baseline arousal because although the PTSD group showed higher SCL, these differences did not reach significance. This finding is in line with recent reports of increased pupil dilation, which has been associated with increased sympathetic arousal (Andreassi, 1989) and amygdala activation (Demos, Kelley, Ryan, Davis, & Whalen, 2008), in PTSD to negatively valenced images (Kimble et al, 2010). Although the PTSD group also displayed increased pupil dilation, there was, however, no evidence of a specific increase in pupil dilation to traumatic stimuli in the PTSD group.…”

“…The key finding of increased number of initial fixations to trauma-related words in PTSD is consistent with previous eye movement studies in PTSD Kimble et al, 2010). We extended earlier findings by showing this initial fixation effect is specific to PTSD compared to trauma-exposed controls.…”

“…Pflugshaupt et al (2005) revealed that spider phobics displayed initial eye movement fixations towards spider stimuli, followed by subsequent fixations away from these stimuli. However, Kimble et al (2010) tested the vigilance-avoidance theory of anxiety by examining time spent on second fixations, but they failed to find evidence for subsequent avoidance following initial fixation in PTSD (Kimble et al, 2010). Such inconsistency may relate to differences in measurements employed, therefore, the current study will examine the direction (rather than time) of subsequent fixations following initial fixation to test the vigilance-avoidance model in a PTSD sample.…”

“…Furthermore, they reported a trend for more initial fixations to Iraq images in the high symptom PTSD group. Yet, conclusions from this study are limited as they employed a traumatized, but largely non-PTSD sample (Kimble et al, 2010). The current study will extend this research by examining eye fixations, skin conductance response and pupil dilation in a civilian sample of traumatized controls and PTSD participants.…”

“…A recent study examined eye tracking in traumatized samples and employed pupil dilation as an index of sympathetic arousal (Kimble, Fleming, Bandy, Kim, & Zambetti, 2010). This study compared traumatized Iraq war veterans with high and low levels of PTSD symptoms (although only two participants met diagnostic criteria for PTSD) in relation to eye movements and pupil dilation to neutral or negative images from the International Affective Picture Series (IAPS: Lang, Bradley, & Cuthbert, 1997).…”