Cognitive biases in military personnel with and without PTSD: a systematic review.

Background: Some cognitive biases, such as excessive attention to threat, are associated with PTSD. However, they may be adaptive for military personnel; attending to threat may improve safety for deployed personnel.Aims: The extent to which military personnel with vs. without PTSD differ with respect to specific cognitive biases is currently unclear. This systematic review aimed to address this question.Methods: PRISMA guidelines were followed. Articles were identified using a comprehensive literature search; 21 studies (with 1977 participants) were reviewed.Results: All studies were of "moderate" or "strong" quality. Military personnel with vs. without PTSD used overgeneralised language when describing autobiographical memories and demonstrated impaired performance on a modified Stroop task. Studies using dot-probe paradigms conceptualised attentional response as a dynamic process, fluctuating between bias towards and away from threat; military personnel with vs. without PTSD demonstrated greater fluctuation. Studies using visual search tasks concluded that attentional bias in PTSD involves interference (difficulty disengaging from threat) rather than facilitation (enhanced threat detection). Finally, personnel with vs. without PTSD demonstrated interpretation bias, completing ambiguous sentences with negative rather than neutral endings.Conclusion: The implications for military populations and recommendations for further research and clinical practice are considered.Prospero registration: PROSPERO 2018 CRD42018092235.