Sixteen men had very high combat, exposure but no reported PTSD symptoms either in 1946 or 40 years later. When contrasted with men who experienced PTSD symptoms after similar combat, exposure, these 16 resilient, men did not manifest less neuroticism or less severe combat; but, they did as young adults manifest, more “mature” see more defenses. The 16 men with high combat, exposure and mature defenses (age 20 to 47) reported only an eighth as many PTSD symptoms as the 18 men

with similarly high combat, exposure and less mature defenses (F 9.5, P=.000 two-tailed, df=33). However this Inhibitors,research,lifescience,medical example does not exclude the possibility that brains altered by PTSD, like brains Inhibitors,research,lifescience,medical altered by traumatic brain

injury (eg,Phineas Gage) or alcohol, subsequently manifest less mature mechanisms. At. present many imaging studies have illuminated the brain circuits underlying PTSD,22,23 social anxiety, and phobia.24 Only a few25-27 have begun tentatively to understand how the brain adapts (downregulates) the effects of conflict. À study by Westen et al28 helped clarify the brain pathways by which partisan voters altered unwelcome facts. The brain “reward” neurons in the striatum and nucleus accumbens appeared to be involved, providing a basis for reinforcing Inhibitors,research,lifescience,medical specific mechanism choices for downregulation. A recent study by Nili and colleagues29 illuminates a putative pathway leading to downregulation of (or dissociation from) fear. Hopefully, the next. 10 years of neuroimaging will bring increasing clarity to the field. Conclusion The concept of involuntary coping mechanisms, (the “politically correct” renaming of the now outmoded (?) Inhibitors,research,lifescience,medical Inhibitors,research,lifescience,medical term, “ego mechanisms of defense”), is too valuable to be discarded by

neuroscience because of its association with Sigmund Freud and psychoanalysis. The diagnostic and prognostic validity of such “mechanisms” in longitudinal studies more than make up for their unreliability and difficulty in rating. The task of neuroscience is to continue to use neuroimaging no to identify and to understand the neural connections of such mechanisms.
It is important to distinguish between immediate and longer-term PTSD reactions. Most diagnostic systems have distinguished between these two types of trauma response because acute stress reactions are frequent, but often transient, and they need to be distinguished from the less common persistent PTSD responses. In terms of the persistent responses, PTSD is described in the American Psychiatric Association’s DSM-IV as an anxiety disorder that comprises five major criteria.4 First, one must have been exposed to or witness an event that is threatening to safety, and one must respond to this event with fear, horror, or helplessness.