Figure 1.
Tasks and stimuli for the study.
Representative stimuli and responses for two of the drawing conditions. In mark making, the name of a geometric figure and a direction for drawing it are presented. Blind drawing (not shown in the figure) has exactly the same stimuli, but no response is observable on the drawing tablet. In copying, an object and a starting point for drawing are indicated, and the subject creates a copy of the object in the space to the right, with the object continually in view.
Figure 2.
Brain activations for mark making.
a) Mark making vs. fixation. b) Mark making vs. blind drawing. Data are corrected for multiple comparisons using FDR p<0.01. Activations shown in Figures 2–5 are rendered onto an inflated brain of one of the subjects in the study (Subject 4) as normalized into Talairach space. The color bars in Figures 2–5 reflect the t score of the activated voxels for a given contrast. Abbreviations: FEF: frontal eye fields; IPS1/2: segments 1 and 2 of the intraparietal sulcus; IPS3/4: segments 3 and 4 of the intraparietal sulcus; MFG: middle frontal gyrus; MT: middle temporal; SMC: sensorimotor cortex; SPL: superior parietal lobule.
Table 1.
Talairach coordinates for mark making, blind drawing, and the contrast between mark making and blind drawing.
Figure 3.
Brain activations for copying: Lateral view.
a) Copying vs. fixation. b) Copying vs. mark marking. Data are corrected for multiple comparisons using FDR p<0.01. See legend to Figure 2 for abbreviations.
Figure 4.
Brain activations for copying: Medial view.
a) Copying vs. fixation. b) Copying vs. mark marking. Data are corrected for multiple comparisons using FDR p<0.01. The left side of the slices is the left side of the brain, as indicated by the L (left) and R (right) symbols. The Talairach z coordinate is shown below the slices. Abbreviations: IFG: inferior frontal gyrus; SMA: supplementary motor area.
Table 2.
Talairach coordinates for copying and perception.
Figure 5.
Brain activations for motion perception.
a) Perception vs. fixation. b) Mark making vs. perception. Data are corrected for multiple comparisons using FDR p<0.01. The blue oval in panel a indicates the region of the sensorimotor cortex for copying not activated in motion perception. See legend to Figure 2 for abbreviations.