MAPT and Alzheimer disease: We found that, even after controlling for regional Aβ and regional tau, higher neural excitability was positively correlated with brain hypometabolism, indicating that altered local excitability that contributes to E/I imbalance is associated with hypometabolism in AD beyond what was accounted for by regional tau (Fig. 4F; F = 13.54, P = 0.0016).