Psychological and physiological predictors of the development and modulation of instrusive images
Abstract
Researchers have suggested that engaging in visuospatial tasks, such as the videogame
Tetris™, following a trauma may interfere with the development of intrusive images
associated with posttraumatic stress disorder (PTSD). The present study attempted to
replicate this finding using a trauma film paradigm. Furthermore, we were interested in
identifying if participants who played Tetris would show changes in other symptoms
associated with PTSD, such as enhanced startle responses. Participants (N = 129) were
asked to view a film with traumatic content and were then randomly assigned to play
either Tetris or to sit quietly for 10 min. Psychological reactivity (positive affect, negative
affect, and dissociation) and physiological reactivity (cardiac measure of sympathetic and
parasympathetic activity, heart rate, and salivary alpha amylase) were examined as
potential predictors of the frequency of intrusive images. Our findings indicated that
intrusive images occurred significantly less often amongst individuals assigned to the
Tetris game-play condition. We were able to identify that the frequency of intrusive
images was modulated by patterns of sympathetic arousal, dissociation, and affective
reactivity. Furthermore, our results indicated that individuals who engaged in the Tetris
task showed a heightened startle response to aversive material. These findings are
discussed in terms of their relevance to etiological models, and the prevention of PTSD.