The capacity for emotional regulation is one of the major causalities of significant early trauma. Traumatized individuals often suffer significant mood swings, anger, irritability, and profound depression. Numerous studies have established that a history of child abuse increases major depression approximately three-fold compared with non-abused individuals.
Disruptions in attachment, the fundamental caregiver-child bonding, are believed to be primarily responsible for the difficulty in developing trusting, reciprocally mutual relationships. Difficulties with modulation of anger and affect further compromise this process.
Finally, research is finding that traumatic experiences can actually affect the development of the brain and impair important neuroendocrine systems. Major hormonal systems such as the hypothalamic-pituitary-adrenal axis, which plays a crucial biological role in buffering the physical effects of stress, are significantly dysregulated in victims of childhood trauma.
In addition, the sympathetic nervous system—sometimes referred to as the “fight or flight” system—has been found to be hyperactive, leading to increased arousal and hypervigilance in trauma victims. This, in turn, probably contributes to hyperarousal, poor concentration, and increased irritability, which extract their toll in school and social success.
 “Mobilizing Trauma Resources for Children,” January 8, 2004, William W. Harris, Ph.D., Children’s Research and Education Institute; Frank W. Putnam, M.D., Children’s Hospital Medical Center, Cincinnati, Ohio; John A. Fairbank, Ph.D., UCLA-Duke University National Center for Child Traumatic Stress.