Defining Acute Stress Reactions to support large scale combat operations

The United States military anticipates that future warfare will involve large scale combat operations (LSCO). The expected nature of LSCO will likely increase the occurrence and severity of Acute Stress Reactions (ASRs), responses to extreme stressors characterized by cognitive, emotional, somatic/physical, and behavioral symptoms. Conceptualizations of ASR vary, with ASRs defined as a disorder in the 10^th version of the International Classification of Diseases (ICD) and considered a non-diagnosable stress reaction by the US military. The diversity in the conceptualizations of ASR has made studying and developing solutions for ASR difficult. Incorporating previous conceptualizations and emerging research, a definition of ASR is proposed that identifies ASR symptom domains, clarifies the timeline in which ASR may occur, and specifies impact of ASR on functioning and neurocognition. To our knowledge, this manuscript is the first to (1) systematically review the current definitions of ASR, (2) specifically discuss ASR in a LSCO context, and (3) present a comprehensive definition of ASR.