Default Mode Network Dysfunction in Adults with Prenatal Alcohol Exposure

Abstract Prenatal alcohol exposure (PAE) is known to cause significant cognitive and attentional dysfunction. Given the relationship between default mode network (DMN) activity and task-related attentional modulation, it is possible that PAE affects activity of this network. In the present study, task-related deactivation as well as structural and resting state functional connectivity of the DMN were examined using diffusional tensor imaging and functional magnetic resonance imaging in non-dysmorphic and dysmorphic PAE populations and compared to healthy controls. The dysmorphic PAE group was found to have reduced DMN deactivation as compared to controls, indicating poorer attentional modulation during the cognitive task. Additionally, structural connectivity and baseline functional connectivity were lower in both PAE groups as compared to controls. Primarily the findings suggest that learning problems seen with PAE may be a combination of general attentional and specific cognitive deficits. A secondary implication is that DMN activity is affected to varying extents depending on the degree of PAE.