IntroductionPost-traumatic stress disorder (PTSD) is a widely discussed topic, with the wars in Iraq and Afghanistan continuing. Soldiers returning from deployment are at higher risk due to events they experience overseas. With the subject being as well known as it is due to the wars, it is no wonder that it has caused a strong push in the field of psychology/neuropsychology to fully understand what PTSD actually is and where it is located in the person. Determining where the effect of PTSD actually lies in the brain is the key to understanding it better and possibly finding a way to make treatment better and hopefully more specialized for the individual instead of diagnosis and d general treatment. Research conducted to date has indicated that there are three main areas of the brain that are most affected by PTSD. The affected areas that will be addressed are the hippocampus, amygdala and anterior cingulate cortex. Each area mentioned has been the subject of hypotheses and studies. PTSD doesn't just affect soldiers, so research has been done with survivors of sarin gas attacks, police officers, trapped coal miners, survivors of sexual and physical abuse. Keeping the pool of study subjects broad and varied gives a better picture of the population as a whole, as anyone can fall prey to PTSD. Additionally, because the topics vary, it allows researchers to take a broader view of the disorder and whether or not people are predisposed to suffering from PTSD. Diagnostic CriteriaTo study PTSD and the brain, one must look at the criteria for PTSD and how it affects the individual on a daily basis. Since there are multiple parts of the brain affected by the disorder, it makes sense that the affected regions correlate... middle of article ......the prefrontal cortex and amygdala. " Neuroscientist (2009): 540- 548. Pubmed.Pavic, Ladislav et al. “Smaller right hippocampus in veterans with post-traumatic stress disorder.” Psychiatry Research: Neuroimaging (2007): 191-198. Reduced anterior cingulate gray matter density associated with history of posttraumatic stress disorder in PTSD.” Annals of New York Academy of Sciences (2006): 67-79. Pubmed. Woon, Fu Lye et et al. “Hippocampal volume deficits associated with exposure to psychological trauma and posttraumatic stress disorder in adults: a meta-analysis” Advances in Neuro-Psychopharmacology and Biological Psychiatry (2010): 1181-1188. Psychological information.