The Biological Response to Psychic Trauma: Mechanisms and Treatment of Intrusion and Numbing [Abstract]

Abstract

The recognition that trauma is qualitatively different from stress and results in lasting biological emergency responses following traumatic experiences may account for the biphasic trauma response, and the accompanying memory disturbances. The past decade has seen rapid advances in our understanding of the underlying biology of this physioneurosis. In addition to classically conditioned physiological reactions, changes now have been demonstrated in startle response in people with post-traumatic stress disorder and in central nervous system catecholamine, serotonin, and endogenous opioid systems. This paper reviews the research data which have demonstrated changes in these systems and explores how these biological changes may be related to the characteristic hyper-reactivity, loss of neuromodulation, numbing of responsiveness, dissociative states, and memory disturbances seen in PTSD. There is growing evidence that trauma has different biological effects at different stages of primate human, development. This article relates these findings to the studies which have demonstrated clear linkages between childhood trauma, and a variety of psychiatric disorders, including borderline personality disorder, and a range of self-destructive behaviors.

KEY WORDS: Post-traumatic stress disorder, psychobiology, arousal, memory, self-destructive behavior., psychopharmacology