Posteromedial cortex glutamate and GABA predict intrinsic functional connectivity of the default mode network
NeuroImage September 18, 2012 Dimitrios Kapogiannis, David A. Reiter, Auriel A. Willette et al. 212 citations
The balance of excitatory and inhibitory neurotransmitters in a key brain region strongly predicts how well the brain's default mode network (DMN) communicates internally. In 20 healthy men, glutamate and GABA levels in the posteromedial cortex (a central DMN node) explained about half of the variation in the network's intrinsic functional connectivity. Glutamate correlated positively and GABA correlated negatively with DMN connectivity; the glutamate/GABA ratio also correlated positively. Age had no independent effect. No other brain network showed this relationship. The findings suggest that local neurotransmitter concentrations within a network hub can predict the functional integrity of that entire network.