An overview of functional, structural and neurochemical imaging studies in individuals with a clinical high risk for psychosis

In recent years, a growing literature has emerged examining the neurobiological correlates of clinical high risk (CHR) for psychosis. Using a range of neuroimaging techniques, alterations in brain function, structure and chemistry have been reported in CHR subjects. In this article, we provide an overview of studies that have used MRI, PET and multimodal imaging to examine neurobiological abnormalities in CHR subjects. These studies have shown that several abnormalities in brain neurophysiology, anatomy and chemistry, which are fundamental to schizophrenia, are also present in people at very high risk of developing the disorder. These abnormalities may represent vulnerability markers that can be used to predict later conversion to psychosis. The future perspectives and limitations of this approach are discussed.