After trauma the world is experienced with a different nervous system. The survivors energy now becomes focused on suppressing inner chaos, at the expense of spontaneous involvement in their lives. These attempts to maintain control over unbearable physiological reactions can result in a whole range of physical symptoms, including fibromyalgia, chronic fatigue, and other autoimmune diseases. This explains why it is critical for trauma treatment to engage the entire organism, body, mind, and brain. Bessel A. van der Kolk, The Body Keeps the Score: Brain, Mind, and Body in the Healing of Trauma

The Body Keeps the Score by Bessel van der Kolk