Neurodevelopment and Adult Psychopathology
It is a contemporary cliché to talk about the overwhelming flood of neuroscientific data on possible etiologies of mental illness. Here is a book that attempts to help the overwhelmed in the way a good teacher does, by starting with basic principles.
This carefully-thought-out text, edited by Dr. Keshavan from Pittsburgh's Western Psychiatric Institute and Clinic and Dr. Murray of London's Institute of Psychiatry and Kings College, is divided in three sections. The first focuses on normal brain development; the second looks at research findings that influence current theories of adult psychiatric illness, particularly schizophrenia; and the third provides a range of developmental models to explain this disorder based on current data, plus suggested directions for future research. Given its neurobiological focus, the book will be most accessible to professionals with some basic science background.
The first section usefully updates readers on key findings of basic neuroscience research. It outlines primate neurodevelopment and its genetic underpinnings, emphasizing the principles of how adult neurons are organized and connected in the brain and where potential genetic defects may occur. Additional chapters provide a helpful explanation of studies of the developing brain using magnetic resonance imaging, (including functional MRI), magnetic resonance spectroscopy, and positron emission tomography. Although the details may lose some readers, the concepts are quite clearly explained. Finally, this section includes a fascinating chapter by Stephen J. Suomi looking at the possible impact of experience and environment on biological systems and behavior by examining work on rhesus monkeys.
The middle section, with its emphasis on schizophrenia, covers a spectrum of research approaches to neurodevelopment and psychopathology, including longitudinal birth cohort studies, developmental theory and analysis of epidemiologic data, gender differences in schizophrenia, comparisons with other "neurodevelopmental" disorders such as obsessive-compulsive disorder, and structural imaging studies. Each chapter explicitly states the uses, limitations, and future potential of each method.
This panoply of concepts and thoroughly documented data culminates in the final section—three chapters outlining possible models of the development of schizophrenia. Irwin Feinberg presents a late developmental model that focuses on neurologic changes during adolescence such as synaptic pruning and the possible role for sex hormones, including adrenal androgens. Dr. Murray and three coauthors outline their "dysplastic net" hypothesis, an early developmental model that proposes a dysplastic process in the second half of gestation resulting in disrupted connections between different parts of the cerebral cortex.
The final chapter, by Dr. Keshavan, ties together these two theories by pointing out that early brain injury could have an impact on the later pruning and final organizational process that seems to close the doors on brain plasticity. His summary of future directions in research is succinct and sensible.
The net effect is that the reader comes away still overwhelmed by the complexity of the schizophrenic spectrum of illness, but considerably more informed about current thinking on its etiology.
Dr. DeJong is a psychiatric resident at the University of Massachusetts Medical Center in Worcester.
