Copyright 2012 Aileen M. Echiverri-Cohen - University of Washington

study inhibition pre- and post-treatment. Specifically, this study examined whether inhibition
changes with 10 weeks of prolonged exposure, a variant of an exposure-based treatment, or
sertraline, the best-studied SSRI, for chronic PTSD. Treatment modality and treatment responder
were examined to ascertain whether they change inhibition differentially. In addition, pre-
treatment inhibitory deficits were examined as a predictor of change in trauma-related
symptoms. Finally, individual difference factors such as age, sex, and education were examined
as predictors of changes in inhibition. Individuals who made greater improvements with
prolonged exposure showed faster improvements in inhibition on the critical inhibitory lag of the
attentional blink task than sertraline, showing a large effect for this interaction, and pointing to
potentially different mechanisms of treatment response in PTSD. Related to this, better inhibitory
functioning on PPI, with a large effect at trend level, was associated with better treatment
response, consistent with prepulse inhibitory functioning potentially serving as pre-treatment
biomarker for treatment response. Finally, age contributed to slower improvements in a critical
inhibitory lag of the attentional blink task over time, suggesting older individuals are associated
with making less changes in inhibitory processes. Thus, differential modulation in fundamental
attentional inhibitory processes by treatment responders suggests differential specificity in how
prolonged exposure and sertraline normalize inhibitory processes. Further, prolonged exposure
and sertraline may use specific pathways in how they bring about therapeutic change, however
ultimately converge on a final common pathway in reducing amygdala reactivity.