From Science Daily:
How does the cross-talk between brain networks change when working memory — the mental assembly of information needed to carry out a particular task — is engaged? Investigators at Massachusetts General Hospital (MGH) have found that dopamine signaling within the cerebral cortex can predict changes in the extent of communication between key brain networks during working memory. Their findings receiving online publication in Science Advances may lay the groundwork for studies of how disruptions in dopamine signaling contribute to working memory deficits that are characteristic of schizophrenia and other psychiatric disorders.
“Our principal finding is that dopamine signaling within the cortex predicts the extent to which the frontoparietal control network — which directly mediates working memory performance — becomes disconnected from the default network — which is active when the brain is awake but directed towards internal tasks, such as thinking about past or future events,” says Joshua Roffman, MD, of the MGH Department of Psychiatry, lead and corresponding author of the paper. “The disengagement of these two networks is what allows us to shift our focus away from internal events and towards the performance of many types of cognitive tasks.”
For their investigation the MGH team utilized the first device capable of simultaneous MRI and PET imaging, which is located at the Martinos Center for Biomedical Imaging at MGH. The ability to conduct both scans at the same time allows real-time measurement of both dopamine signaling — using a PET imaging agent that binds to D1 dopamine receptors –…