Functional magnetic resonance imaging (fMRI) of the brain can be used to screen soldiers (and civilians) for a high risk of committing suicide, according to a study of 50 IDF personnel conducted by Tel Aviv University researchers. The study, headed by Prof. Talma Hendler of the university's Sackler Faculty of Medicine's psychology and psychiatry department and Tel Aviv Sourasky Medical Center's brain function center, was recently published in Proceedings of the National Academy of Sciences (PNAS), a US journal. High risk for suicide was gauged by assessing which soldiers were vulnerable to symptoms connected to post-traumatic stress disorder (PTSD). The brain regions most relevant to the prediction are the amygdala (responsible for emotional processing in the brain and warning people to avoid danger), the hippocampus (which processes memory), and the prefrontal cortex (which gives emotional and personal significance to stimuli). Two-fifths of all individuals will at some time in their life experience at least one significant traumatic event, and most of them will react soon after with PTSD symptoms such as anxiety, bad moods, sleep problems and upsetting thoughts. About one-fifth of these are liable to suffer from long-term PTSD symptoms such as depression and post-traumatic anxiety, while others will recover without therapy. Until now, except for certain blood tests developed experimentally at Hadassah University Medical Center in Ein Kerem, there has been no objective way to determine who will recover on their own and who will need help. Since early diagnosis and treatment are vital for preventing long-term PTSD, a harmless scan could prove beneficial, said Hendler. IDF paramedics - who volunteered for the study and constitute the first line of soldiers who treat the wounded - were tested before their basic training and 18 months later when they were already working as battlefield paramedics. During their service, two-thirds of the paramedics reported having increased stress symptoms such as nightmares, repeated unpleasant thoughts and a bad moods. The fMRI scans showed that these symptoms increased when the amygdala was more active just before exposure to traumatic events and the hippocampus was more active after the events. The tests also showed that as the negative symptoms developed, the hippocampus communicated less with the prefrontal cortex. This demonstrates flexibility in brain activity and brain regions connected with emotional reactions to stress, Hendler said. This finding points to the potential of changing the brain using medications or psychological treatment after exposure to trauma. The findings, she concluded, show that "there is a model of activity and brain reaction characteristic of every individual, who can be sent for early individual treatment after being exposed to a traumatic event." However, Hendler suggested that fMRI should not be used as a tool to keep individual soldiers out of sensitive military units but to help psychiatrists and psychologist treat the more susceptible soldiers earlier and better. Meanwhile, World Suicide Prevention Day will be marked around the globe on Thursday. The International Association for Suicide Prevention (established nearly 50 years ago) set aside the day to promote the prevention of suicidal behavior, alleviating its effects and providing a forum for academics, mental health professionals, crisis workers, volunteers and suicide survivors.