Figure 2.
Global signal amplitude (in units of percent change) as a function of preprocessing approach for 30 scans. Bars indicate mean plus or minus one standard deviation. With respect to the MinProc set, the means of the normalized variances of the global signals are 0.52, 0.21 and 0.07 for the Leg+Mo, Leg+Mo+Phys, and Leg+Mo+Phy+WM/CSF sets, respectively. As an example, this means that the variances of the global signal in the Leg+Mo set are on average 52% of the respective variances of the global signals in the MinProc set. These data are from the eyes-closed scans in the pre-dose control, post-dose control, and pre-dose caffeine sessions described in (Wong et al., 2013)