Figure 2: Time course of the BOLD signal of the activated region in the anterior cingulate cortex averaged across the voxels of the ROI and across subjects. The graphics shows the raw signal (blue line) and an interpolated signal by using polinomial fitting (red line). The volumes from 1 to 40 (2 minutes) are the first rest time, the volumes from 41 to 240 (10 minutes) are the active time, the volumes from 241 to 280 (2 minutes) are the second rest time.