Post-traumatic stress disorder (PTSD) is a mental disorder caused by experiencing or witnessing a truly traumatic, tragic, or terrifying event. Those who suffer from PTSD may have persistent, frightening thoughts and memories of what they have been through and may end up feeling emotionally numb, especially around people they are close to. Seeing things that remind the individual of the accident can cause great distress, which leads them to avoid certain places or situations that bring back memories, even anniversaries of the event can bring back memories and are often very difficult ( psychocentral). Statistics from the Department of Veterans Affairs show that 9 out of 11 veterans from Iraq and Afghanistan are diagnosed with post-traumatic stress disorder. That's nearly 30% of the 834,463 veterans who are treated in VA hospitals and clinics (The Daily Beast). Some symptoms of PTSD are recurring flashbacks, high levels of anxiety, known as hyperarousal. People also avoid or cloud their memory of the event (Wikipedia). Reliving the trauma can present itself in the form of nightmares or disturbing memories during the day. Nightmares and memories come and go randomly for people. Some may not experience them for weeks at a time and then experience them every day for no reason. People may also experience sleep problems, depression, feelings of detachment or numbness, or become easily frightened. There may also be a loss of interest in things they used to enjoy and difficulty feeling affectionate. People with PTSD may become incredibly irritated or more aggressive than before. It can get to the point where the person becomes violent. (psychocentral) Other causes of post-traumatic stress disorder are sexual violence, torture and events that put the life of oneself and/or a loved one at risk...... at the center of the document..... .in progress.Works CitedSmith, Melinda, M.A., and Jeanne Segal, Ph.D. “Posttraumatic Stress Disorder (PTSD).” Helpguide.org.Helpguide.org, March 2014.Web. April 26, 2014.Grohol, John M., PSY.D. “Posttraumatic Stress Disorder (PTSD).”PsychCentral.com. Psych Central, November 19, 2013.Web. April 25, 2014. “Posttraumatic Stress Disorder.” Wikipedia. Wikimedia Foundation, April 27, 2014.Web. April 27, 2014. “Posttraumatic Stress Disorder (PTSD).” NIMH RSS. National Institutes of Health, ND Web. April 26, 2014. Reno, Jamie. "The Hero Project." The daily beast. Newsweek/Daily Beast, October 21, 2012. Web. April 25, 2014. “Posttraumatic Stress Disorder.” Post-traumatic stress disorder. International. Wellness Directory, NDWeb. April 27, 2014. “Feds May Allow Researchers to Study Treating PTSD with Medical Marijuana.” -RTUSA. RT, March 18, 2014.Web. April 27. 2014.