Resting-State Functional Connectivity in Psychiatric Disorders.

The idea that serious mental illnesses, such as autism and schizophrenia, result fromabnormalconnectivityamong largescale brain networks is gaining widespread acceptance. Efforts to test hypotheses of dysconnectivity have historically been hindered by tools with insufficient spatial resolution to investigatehumanbrain connectivity in vivo and an incomplete understanding of the large-scaleorganizationof the brain, the so-called connectome. Thedevelopment of resting-state functional connectivitymagnetic resonance imaging (rs-fcMRI) has profoundly affected our understanding of the functional organization of the brain, both in health and illness. The investigation by Cerliani and colleagues1 in this issuedescribesabnormal cortical-subcortical connectivity in the brains of individuals with autism. In this Editorial, we briefly review rs-fcMRI methods; summarize several key rs-fcMRI findings in 2 exemplary dysconnectivity-associatedpsychiatric illnesses, schizophrenia and autism; and discuss the potential uses for rs-fcMRI in the search for biomarkers of psychiatric disorders.