Fig 5. Power in spontaneous BOLD fluctuations in resting and visual stimulation conditions. Resting state (blue) condition shows the shift of frequency distribution to higher frequencies compared with natural visual stimulation condition (red). Spectra are averaged across 6 subjects for each condition. Shaded areas represent standard error of the mean as a function of frequency across the population. The pair-wise t test for each frequency range (0–0.02 Hz and 0.02–0.05 Hz) indicates statistically significant differences between the 2 conditions for each of the 2 ranges.