The Predictive Value of Inhibitory Control for PTSD Symptom Clusters

Abstract

Executive function, especially inhibitory control has shown to play an important role in Posttraumatic stress disorder (PTSD). Impaired inhibitory control is found to be related to PTSD and PTSD symptom severity. Researchers are still disagreeing about the relationship between inhibitory control and the four PTSD symptom clusters (intrusions, avoidance, emotional numbing and hyperarousal). The current study examines whether the four PTSD symptom clusters can be predicted by inhibitory control. Forty-one Dutch military veterans and active military staff members with PTSD completed the online questionnaires Beck Depression Inventory (BDI-II), PTSD Checklist for DSM-5 (PCL- 5), Life Events Checklist for DSM-5 (LEC-5) and a Go/No-Go task, as a measure for inhibitory control. A hierarchical multivariate regression analysis was conducted. At the first stage depression was treated as predictor to control the influence of the comorbidity. At the second stage inhibitory control was added as predictor. The analyses did not reveal a multivariate effect of inhibitory control on the symptom clusters. Comorbid depression, however, appears to have great predictive value for the clusters. Thus, inhibitory control may not be able to predict the four PTSD symptom clusters, whereas depression does. This could be explained by a cluster-exceeding influence of inhibitory control, or alternatively with various methodological limitations, as sample size of uncontrolled environment of the task.