Fig. 4.

This figure shows the mean ± SEM validity effect (invalid minus valid reaction time), preoperatively and postoperatively, for ipsilateral and contralateral responses. Preoperatively, the validity effect is equal for responses to either side. The validity effect is not seen in the postoperative data on the contralateral side, indicating an abolition of the benefit of attentional orienting to contralateral cues. There was no change in the magnitude of the validity effect on the ipsilateral side.