Regional GABA Concentrations Modulate Inter-network Resting-state Functional Connectivity

Xi Chen, Xiaoying Fan, Yuzheng Hu, Chun Zuo, Susan Whitfield-Gabrieli, Daphne Holt, Qiyong Gong, Yihong Yang, Diego A Pizzagalli, Fei Du, Dost Ongur
2018 Cerebral Cortex  
Coordinated activity within and differential activity between large-scale neuronal networks such as the default mode network (DMN) and the control network (CN) is a critical feature of brain organization. The CN usually exhibits activations in response to cognitive tasks while the DMN shows deactivations; in addition, activity between the two networks is anticorrelated at rest. To address this issue, we used functional MRI to measure whole-brain BOLD signal during resting-state and task-evoked
more » ... onditions, and MR spectroscopy (MRS) to quantify GABA and glutamate concentrations, in nodes within the DMN and CN (MPFC and DLPFC, respectively) in 19 healthy individuals at 3 Tesla. We found that GABA concentrations in the MPFC were significantly associated with DMN deactivation during a working memory task and with anti-correlation between DMN and CN at rest and during task performance, while GABA concentrations in the DLPFC weakly modulated DMN-CN anti-correlation in the opposite direction. Highlighting specificity, glutamate played a less significant role related to brain activity. These findings indicate that GABA in the MPFC is potentially involved in orchestrating between-network brain activity at rest and during task performance.
doi:10.1093/cercor/bhy059 pmid:29608677 fatcat:mezqg4oaybgovafjvgmvbnd3ky