Figure 6.

Brain regions involved in task switching. A, Time for initiating cursor movements to a target appearing at an unpredictable location on the screen during the target-chasing task. Columns refer to the first, second, and third movements and for movements to targets during the steady-state performance (Ss) recorded in bimanual and unimanual trials. Heights of columns give mean values computed across participants for data pooled across the left-hand and right-hand mapping rule, and error bars indicate 1 SD (n = 16); mapping rule influenced neither hit time nor path index (data not shown). B, The MNI glass brain shows brain areas activated during initiation of the target-chasing task (orange areas) and, for comparison, an outline of prefrontal areas activated during the hand-selection phase in the bimanual trials (purple contours). C, The same brain regions as in A shown on coronal, sagittal, and transversal slices of the brain obtained as described in the legend of Figure 3C. Vertical line on sagittal slices indicates the position of the vertical plane passing through the anterior commissure. Put., Putamen; POJ, parieto-occipital junction. D, Time course of the BOLD signals during performance of the target-chasing task averaged across all voxels in the clusters labeled by a, b, and c in B for data obtained during each type of trial. Format and data processing as in Figure 3B.