Psychophysiological Investigation of Combat Veterans with Subthreshold Post-traumatic Stress Disorder Symptoms.

Objective: Military service members (SMs) with subthreshold combat-related post-traumatic stress disorder (PTSD) symptoms often have clinically significant functional impairment, even though they do not meet full PTSD criteria. We therefore assessed the psychophysical responses of SMs, upon their return from Afghanistan or Iraq, to a fear conditioning paradigm to better understand the biological underpinnings of symptom severity.

Methods: Heart rate (HR), skin conductance, electromyography startle, and respiratory rate (RR) were monitored throughout three distinct phases of the paradigm-fear acquisition, fear inhibition, and fear extinction-while plasma catecholamines (epinephrine, norepinephrine, and dopamine) were measured at the end of fear inhibition.

Biomarkers of post-deployment resilience among military service members.

The development of PTSD after military deployment is influenced by a combination of biopsychosocial risk and resilience factors. In particular, physiological factors may mark risk for symptom progression or resiliency. Research in civilian populations suggests elevated catecholamines after trauma are associated with PTSD months following the trauma.

Predictors of Neurocognitive Syndromes in Combat Veterans.

Traumatic brain injury, depression and posttraumatic stress disorder (PTSD) are neurocognitive syndromes often associated with impairment of physical and mental health, as well as functional status. These syndromes are also frequent in military service members (SMs) after combat, although their presentation is often delayed until months after their return. The objective of this prospective cohort study was the identification of independent predictors of neurocognitive syndromes upon return from deployment could facilitate early intervention to prevent disability.

Catecholamine responses to virtual combat: implications for post-traumatic stress and dimensions of functioning.

Posttraumatic stress disorder (PTSD) symptoms can result in functional impairment among service members (SMs), even in those without a clinical diagnosis. The variability in outcomes may be related to underlying catecholamine mechanisms. Individuals with PTSD tend to have elevated basal catecholamine levels, though less is known regarding catecholamine responses to trauma-related stimuli.