Action timing in an isochronous tapping task: Evidence from behavioral studies and neuroimaging

It is easy for people to synchronize actions with external events under conditions in which the temporal pattern of the events can be anticipated as in sensorimotor synchronization. Various models have been proposed to explain the typical observation in such tasks that the action (tap) leads the event to be synchronized (click)—the socalled negative asynchrony. We present two classes of models: One class maintains that the coincidence required by the instructions can be achieved only with respect to brain events (code coincidence). The other class holds that coincidence can be achieved with respect to world events (event coincidence) themselves. Different implications of these two classes for the functional background of negative asynchronies are discussed.