Life involves difficult experiences for all of us. In most cases, we can recover from them and live with the memory of what has been painful. Some events are so traumatic that a person can have difficulties to move forward and function normally again. A person that suffers from post-traumatic stress disorder (PTSD) has usually gone through such a traumatic event. For example, it may have been a danger to his or her life, or a violation of physical integrity. This incident has caused strong feelings of fear, helplessness and/or horror. Anyone who has experienced a traumatic event can suffer from emotional distress and loss of interest. The person might be “shut off” from others. One of the key symptoms of PTSD is that the trauma experience returns again and again. This may include, for example, rapid ”flashbacks”, or severe nightmares. While such recalling of the incident could provoke severe discomfort and/or physical reactions, it could turn into avoidance of different situations that in the slightest way might remind of the traumatic event. In the case of PTSD, it is common to find difficulties in concentrating, insomnia and a sense of increased vigilance.