July 1, 1998
Psychobiology of Posttraumatic Stress Disorder. Edited by R. Yehuda and A.C. McFarlane. Annals of the New York Academy of Sciences, Vol. 821. New York: The New York Academy of Sciences, 1997.
The recent torrent of findings in neuroscience has had an enormous impact on the understanding of psychological trauma. Neurobiological research has begun to uncover the neural mechanisms underlying some of the clinical hallmarks of posttraumatic symptoms and states. This research confirms some long-held perspectives based on clinical research and challenges some others.
Neurobiological research and what it tells us about the phenomena of trauma are important not only to neurobiological researchers but also to trauma researchers and clinicians. This research promises -- and is beginning to deliver -- answers to fundamental questions about the nature of posttraumatic symptoms, its course, and ultimately, new methods for treatment. As the understanding of the neurobiology of posttraumatic symptoms increases, so too will the understanding of how interventions -- psychological and psychopharmacological -- can interrupt those symptom processes. More fundamentally, this new generation of neuroscience research has already upended the old reductionistic assumption that formerly underlay much neurobiological research. The brain not only acts on the environment through its control on mental states and behavior, it also is profoundly altered by its environment.
This book stems directly from a conference of the same title sponsored by the New York Academy of Sciences in September 1996. The book is divided into seven parts. Part 1 covers the epidemiological and empirical basis for studies of the biology of PTSD, including chapters on its prevalence, longitudinal course, and associated comorbid disorders and familial risk factors. Part 2 summarizes the major psychobiological findings in PTSD research. Chapters focus on the sensitization of the hypothalamic-pituitary-adrenal axis, structural brain changes, evidence from neuroimaging studies and psychophysiological reactivity, noradrenergic alterations, and the psychobiology of sleep disturbances in PTSD patients. Part 3 addresses neurodevelopmental issues. Two chapters summarize findings on neurophysiological and neuroanatomical changes associated with chronic childhood abuse, a model of the neurodevelopmental impact of trauma, and a chapter that focuses specifically on the possible mechanisms by which early trauma can induce long-term vulnerability to mood and anxiety disorders. Part 4 tackles the neurobiology of memory impairment in PTSD. Two chapters review, respectively, the performance of PTSD patients on standardized memory tests and content-dependent memory abnormalities in PTSD. Other chapters focus on memory and dissociation, the neurobiology of traumatic memory, hormonal influences on the regulation of memory storage, and a basic chapter on the neural basis of fear conditioning.
Part 5 begins the book's turn toward linking basic neurobiological research to clinical observations of PTSD patients. One chapter provides a detailed review of research on the impact of stress on the structure and function of the hippocampus and its attendant impact on cognitive functioning. Other chapters outline, respectively, the kindling paradigm as an explanatory model of PTSD symptomology, stressor-induced oscillation as a model for the alternation in PTSD between intrusive and avoidant symptoms, and research on the acoustic startle reflex. The section concludes with two overview chapters that summarize animal models that can be applied to PTSD and synthesizes many of the findings presented in earlier chapters.
Part 6 addresses the psychobiology of treatment. The first two chapters summarize, respectively, the findings of studies of drug treatment for chronic and acute PTSD, both addressing the relative inadequacy of available pharmacological treatments. The third chapter summarizes findings on biological markers of PTSD symptomology with the view to designing objective measures of treatment outcome, while the fourth focuses on psychological processes related the recovery from PTSD.
The final section of the book consists of 31 posters presented at the Psychobiology of Posttraumatic Stress Disorder Conference in 1996. The posters detail findings from specific studies on a broad range of topics from cortisol levels in various traumatized groups to electrophysiology and PTSD to MRI assessment of structural abnormalities in PTSD to neurobiological alterations in nonhuman primates.
This volume shares the same limitation inherent in all compendia of research, particularly in such a fast-evolving field: the inevitability of datedness. However, the book provides a mixture of data and synthesis and covers so much material that it is likely to remain a useful reference for some time. In addition to its obvious usefulness to researchers in the field of traumatic stress, the book has much to offer clinicians who wish to understand and integrate into their work the expanding knowledge base on the psychobiology of trauma. Finally, the book would be an excellent addition to the reading list of any advanced graduate-level course in psychological trauma.