“…In the military, after the aforementioned studies on Post Deployment Syndrome and fatigue in Cambodia veterans (De Vries et al, 2000) the Department of Defense also facilitated biological studies in PTSD in alliance with several academic partners to validate the disorder and stimulate research on the disorder. This started with cross-sectional biological studies and later with prospective studies in soldiers, resulting in a flurry of studies that validated what was known and extended the findings because of the use of new designs: Hypothalamus-Pituitary-Adrenal-axis studies (De Kloet et al, 2006) neuroimaging and pain studies (Geuze et al, 2007, 2008), personality (Rademaker, Kleber, Meijer, & Vermetten, 2009), and sleep (Van Liempt et al, 2013). The start of the participation to International Security Assistane Forces deployment was an opportunity to conduct true prospective studies that allowed identification of candidate biomarkers and differentiation of posttraumatic stress, depression, and fatigue (Van Zuiden et al, 2011, 2012), as well as an insight into central brain circuits after deployment (Van Wingen, Geuze, Vermetten, & Fernandez, 2012).…”