Fig. 4

Decreased prefrontal cortex slow-5 (0.01–0.027 Hz) power in FOP patients with high pain levels. a Frequency analyses reveal decrease power within the slow-5 sub-band across multiple channels distributed over the medial and anterior aspects of the prefrontal cortex. A significant effect after FDR correction was observed in channels C2, C5, and C7. * denotes FDR correct p-values, while light green bars in C2, C5, and C7 plots further define the slow-5 sub-band. Mean power spectral density and standard error (shaded area) across all sub-bands (i.e., slow-1 to slow-5) are plotted for low (Pain Level: 0–3; N = 7) and high (Pain Level: 4–10; N = 6) clinical pain FOP cohorts. Clinical pain intensity levels for each patient were collected from each FOP patient just prior to acquisition of the six-minute resting-state fNIRS scan. b Correlation analyses performed across all FOP patients showed that for channels C2, C5, and C7, a greater extent of power suppression within the slow-5 frequency range corresponded with greater clinical pain intensity