Depersonalization is a dissociative disorder whose core feature is a subjectively altered selfhood characterized by a sense of unreality, hypoemotionality, and loss of agency. Even though several sources point to a 1–2% prevalence in Western cultures, by no means ‘rare’ as described by DSM-IV-TR criteria, clinicians often delay or miss the diagnosis leading to unnecessary prolongation of patients' suffering, especially as the disorder is often easier to treat closer to onset and can become quite refractory as years pass. Therefore, it is very exciting to have four books on depersonalization disorder published in only a 5-year span from 2006 to 2010 (the others are by Simeon & Abugel, Reference Simeon and Abugel2006; Baker et al. Reference Baker, Hunter, Lawrence and David2007; Neziroglu & Donnelly, Reference Neziroglu and Donnelly2010), reflecting the considerable research and emerging conceptual and treatment frameworks for a condition that was largely neglected prior to the past 15 years.
Mauricio Sierra's wonderfully concise and rounded new book is a very welcome addition to this new literature, thoroughly referenced up to the year of publication. In eleven chapters, all very engaging to read, the author covers the disorder from all major angles. The chapter on historical perspectives is rich with detailed, intriguing phenomenological observations dating back to the 1800s. It also reviews older theories of depersonalization, which are interesting to compare and contrast to the final state-of-the-art chapter of the book in which the various subjective components of the syndrome are pulled together and tied-in to what we know so far about the neurobiology that subsumes them. The chapter describing the symptoms of depersonalization is particularly useful to clinicians who wish to elicit a full and accurate history of their patients, and often are not familiar with the whole range of subjective experiences that they should inquire about. Also helpful to diagnosis is the Cambridge Depersonalization Scale, by the author, which is included as an appendix.
The book is relatively weak on differential diagnosis, a very important topic given the proneness to diagnosing chronic depersonalization as other things; differential diagnosis is indirectly alluded to and features a little in the chapter on comorbidity. Similarly, the distinction from other dissociative disorders, which also tend to be missed or misdiagnosed, could have been elaborated more extensively. A brief chapter is devoted to the fascinating phenomenon of drug-induced chronic depersonalization and ways of understanding it. The neurobiology chapter is clear and well-written, although it would have made for smoother reading if it had preceded the treatment section. To my mind, one thing missing from the neurobiology chapter is a highlighting of the ways in which the findings for depersonalization contrast with those of mood and anxiety disorders, and are similar to those of other dissociative disorders including dissociative PTSD. Pharmacological treatment options and their rationale are clearly laid out.
The chapter on psychotherapies is too short, and could have benefited from case examples; it does not do full justice to the richness of antecedents that can contribute to the loss of selfhood. Still, it does lay out the fundamentals of psychotherapeutic approaches to the disorder. I was particularly intrigued by the cultural analysis of depersonalization and the notion that vulnerability to the experience may differ between more individualistic versus collectivistic cultures. In all, the book is a ‘must read’ for professionals at all levels of training who want and need to better understand chronic depersonalization in its own right.
