Figure 5 shows the distribution of power in the frequency domain for BOLD signal fluctuations in the DMN component for all three groups. Repeated-measures ANOVA showed a highly significant main effect of frequency (F(43,1)=881.584, p<0.001), but no main effect of diagnosis (i.e. all groups had similar total power). There was a significant frequency × diagnosis interaction (F(43,2)=3.183, p=0.05), indicating that the power was distributed differently for the 3 groups. ANOVAs with Scheffe's post-hoc tests at each 0.02Hz frequency bin showed that the schizophrenia group had significantly less power than controls at the 0-0.02Hz range, and significantly more power at the 0.04-0.06Hz range. The bipolar disorder group, by contrast, had reduced power in the 0.02-0.04Hz range, and increased power in the 0.12-0.14, 0.14-0.16 and 0.18-0.20Hz ranges.
