Images of the brain in psychiatry

In psychiatry, the use of computer-based techniques for constructing images of the brain is relatively recent. Nevertheless, findings that have resulted from their use thus far might provide us with a new perspective in the understanding of mental illness. They raise the possibility that many of the disorders, previously understood primarily in terms of psychosocial factors, are associated with specific abnormalities of brain structure and/or function. Although terms such as NMR, BEAM, RCBF, SPECT and PET are increasingly found in medical and psychiatric journals, few people understand in simple terms the principles on which these techniques are based. In this article the techniques used for constructing images of brain structure and function are explained, and an overview of the findings in psychiatric disorders is presented.