An analysis of inhibitory functioning in individuals with chronic posttraumatic stress disorder

•Inhibitory deficits such as seen in prepulse inhibition and attentional blink may underlie cognitive abnormalities in PTSD.•Deficits in prepulse inhibition were more prevalent in trauma-exposed individuals with PTSD compared to those without PTSD and healthy controls.•Deficits in attentional blink were more prevalent in both trauma-exposed with and without PTSD compared to healthy controls.•Prepulse inhibition and attentional blink were not strongly associated.•These findings suggest a general faulty inhibitory mechanism associated with trauma exposure and PTSD.

Cognitive abnormalities in posttraumatic stress disorder (PTSD) may be a function of underlying inhibitory deficits. Prepulse inhibition (PPI) and attentional blink (AB) are paradigms thought to assess inhibition. Using a sample of 28 individuals with PTSD compared to 20 trauma-exposed and 19 healthy individuals, PPI was examined using white noise that was preceded by a tone, and AB was examined using a presentation of letters in a stream of numbers. Relative to the control group, the PTSD and trauma-exposed groups did not follow the u-shaped pattern in AB, suggesting trauma-exposure and subsequent PTSD are associated with similar impairment in attention. Individuals with PTSD showed reduced PPI compared to trauma-exposed and healthy individuals, suggesting individuals with PTSD exhibit faulty automatic processing. For individuals with PTSD, PTSD severity was associated with a decline in PPI. These findings suggest a general faulty inhibitory mechanism associated with trauma exposure and PTSD.