Modern neuroimaging in psychiatry: towards the integration of functional and molecular information

Thirty-five years of psychiatric imaging along traditional diagnostic boundaries have revealed a great deal about the structural and functional brain changes that accompany mental disorders but not produced reliable biomarkers. One reason may be that clinical syndromes represent the phenotypic expression of many different genotypes and biological pathways. Neuroimaging is now increasingly being used to map out the pathways from genes (obtained from candidate or genome-wide association studies) to the cognitive, emotional and behavioural phenotypes that result in syndromes like schizophrenia or depression. The armamentarium of neuroimaging is becoming increasingly versatile, and now includes methods with considerable spatial, temporal and/or molecular resolution. We can expect that a sophisticated combination of these techniques with genetic and pharmacological information will usher into a new era of psychiatric imaging that will aid a biological classification of mental diseases.