Deployment of visual attention before sequences of goal-directed hand movements.

We examined the allocation of attention during the preparation of sequences of manual pointing movements in a dual task paradigm. As the primary task, the participants had to perform a sequence of two or three reaching movements to targets arranged on a clock face. The secondary task was a 2AFC discrimination task in which a discrimination target (digital 'E' or '3') was presented among distractors either at one of the movement goals or at any other position. The data show that discrimination performance is superior at the location of all movement targets while it is close to chance at the positions that were not relevant for the movement. Moreover, our findings demonstrate that all movement-relevant locations are selected in parallel rather than serially in time, and that selection involves spatially distinct, non-contiguous foci of visual attention. We conclude that during movement preparation--well before the actual execution of the hand movement--attention is allocated in parallel to each of the individual movement targets.