Post-traumatic stress disorder (PTSD)Post-traumatic stress disorder is an anxiety disorder that results from exposure to a traumatic event. When the body feels in danger, it reacts with a “flight or fight” response intended to protect the person from danger. When the body is faced with terror, functions such as memory, emotions and thinking are disabled because they are less important at the moment. This allows the body to focus solely on increasing heart rate, moving more blood to the muscles in order to run, and adding stress hormones to help fight infections and bleeding if injured (site National Alliance on Mental Health Web, 2014). As a result, traumatic experiences are not processed at the time they occur because the body is so focused on immediate physical safety. As a result, these unprocessed memories can arise at any time, without warning, leaving a person with PTSD feeling stressed or afraid even when they are no longer in danger. Currently, scientists are studying ways that could increase the risk of suffering from PTSD. Scientists think genes may play a role in creating fear memories; They identified the genes that make stathmin (a protein necessary for the formation of fear memories) and gastrin-releasing peptide (GRP) (a signaling chemical released in the brain during emotional events), by testing both in mice (National Institute of Mental Health, 2013). In a study of stathmin, “mice that did not produce stathmin were less likely than normal mice to “freeze,” a natural, protective response to danger, after being exposed to a frightening experience. They also showed less innate fear by exploring open spaces more willingly than normal mice” (National Institute of Mental Health, 2013, p...... middle of article ......ses, the influx of troops with low levels of fear of psychiatric casualties and the withdrawal period during which there were large numbers of psychiatric casualties (Kabatchnick, 2009, p. 273). well during the second stage to the interventions put in place until the end of this stage in 1968. From 1968 to 1975, the psychiatric disposition of the troops deteriorated, it was thought that psychiatric disorders were masked by high quantities of The high rate of PTSD among Vietnam War veterans is believed to be attributed to the nature of the conflict itself – “non-existent battle lines, the young age of the soldiers, and public shame.” upon their return to America” (Katchnick, 2009, p. 274) was later officially recognized as a mental disorder in 1979 after the extent of combat trauma. experienced by Vietnam veterans (Kabatchnick, 2009).