Cognitive deficits in schizophrenia and autism are profoundly disabling and, at present, effective treatments are lacking. The goal of our research program is to elucidate the neural bases of cognitive function in health and in neuropsychiatric disorders. We are particularly interested in the contributions of the prefrontal and anterior cingulate cortices to executive functions such as inhibiting reflexive actions in order to permit flexible responding, switching between one activity and another at will, and monitoring outcomes of behavior in order to optimize performance and learn from mistakes. We are using multimodal neuroimaging to precisely define the spatiotemporal signature and structural bases of these executive functions. Our methods include functional magnetic resonance imaging (fMRI), magnetoencephalography (MEG), diffusion tensor imaging (DTI), and studies of saccadic eye movements. Since recent work suggests that executive functions are genetically mediated by common polymorphisms, we are also examining the contribution of these polymorphisms to inter-individual variation in cognitive function. A separate line of inquiry focuses on understanding the role of sleep in consolidating new learning. Patients with schizophrenia do not show normal improvements in memory consolidation after a night of sleep. We are investigating the basis of this failure using overnight polysomnography and behavioral studies. These studies will enrich our understanding of disabling cognitive deficits and can guide the development of targeted interventions.
