HAND DEVIATIONS AWAY FROM VISUAL CUES - INDIRECT EVIDENCE FOR INHIBITION

Previous research has demonstrated that when a stimulus is to be ignor ed, the path of motion towards a target (saccade or manual reach) devi ates away from the to-be-ignored stimulus. Path deviations in saccade and reaching tasks have, however, been observed in very different situ ations. In the saccade tasks subjects initially attended to a cue, the n disengaged attention while saccading to a target. By contrast, in th e selective reaching tasks attention was continuously withdrawn from t he to-be-ignored stimulus, as this was irrelevant throughout the exper iment. In the two experiments reported here, cues similar to those stu died in saccade tasks are examined with selective reaching procedures. Experiment 1 shows that when a coloured light-emitting diode cue, upo n which subjects engage and then subsequently disengage attention, is close to the responding hand, the hand deviates away from the cue. Exp eriment 2 confirms this cue avoidance by showing that, compared with c entral fixation alone, the hand veers away from a central cue. These r esults confirm that the path deviations observed in saccades can also be obtained in manual reaching movements. Such findings support the no tion that eye and hand movements are both affected by inhibitory mecha nisms of attention.