Visuomotor priming

Two experiments were performed to explore a possible visuomotor priming effect. The participants were instructed to fixate a cross on a computer screen and to respond, when the cross changed colour ("go" signal), by grasping one of two objects with their right hand. The participants knew in advance the nature of the to-be-grasped object and the appropriate motor response. Before (100 msec), simultaneously with or after (100 msec) the "go" signal, a two-dimensional picture of an object (the prime), centred around the fixation cross, was presented. The prime was not predictive of the nature of the to-be-grasped object. There was a congruent condition, in which the prime depicted the to-be-grasped object, an incongruent condition, in which the prime depicted the other object, and a neutral condition, in which either no prime was shown or the prime depicted an object that did not belong to the set of to-be-grasped objects. It was found that, in the congruent condition, reaction time for initiating a grasping movement was reduced. These results provide evidence of visuomotor priming.