Regional homogeneity of resting state fMRI signals predicts Stop signal task performance.

It has been suggested that resting-state functional magnetic resonance imaging (RS-fMRI) is a promising tool to study the relation between spontaneous brain activity and behavioral performance. However, little is known about whether the local synchronization of spontaneous brain activity could predict response inhibition. In the current study, we used regional homogeneity (ReHo) to measure the local synchronization of RS-fMRI signals, and then investigated the relationship between ReHo and individual differences in response inhibition, as evaluated by the stop signal reaction time (SSRT) in a Stop signal task. The results showed that ReHo of RS-fMRI signals could successfully predict SSRT. Specifically, positive ReHo-SSRT correlations were observed in the bilateral inferior frontal cortex (IFC) and three critical components of the default mode network (DMN), and negative ReHo-SSRT correlations were observed in the rolandic area/posterior insula and the bilateral middle occipital cortex. The present results indicate the possible influence of the IFC and rolandic area/posterior insula on the efficiency of response inhibition, and demonstrate the importance of the DMN for the efficiency of cognitive task performance.