Neural Dynamics for a Sudden Change in Other’s Behavioral Rhythm

Abstract

Our communication includes behavioral synchronization with sudden changes of other’s rhythms. However, it is not clear about its neural mechanism. Here, we compared the behaviors and brain activities between the normal and autism spectrum disorder (ASD) subjects in an alternating tapping task which required subjects to synchronize the tapping intervals with a virtual person (PC program) who tapped at a constant interval or a variable interval. Behavioral results showed no significant difference between the normal and ASD subjects under the constant-interval condition. In contrast, the rates of synchronization of the normal subjects were higher than those of the ASD subjects under the variable-interval condition. EEG results showed alpha modulations (10–12 Hz) in the motor cortex were larger for the normal subjects than the ASD subjects under the variable condition, whereas there was no difference under the constant condition. Our results suggested that the synchronization with other’s sudden variable rhythms would be associated with the motor alpha modulations.