Separation of 1/f^χ slope and narrowband oscillatory power. A, Low-frequency (2–30 Hz) power spectrum for pmHG and alHG during the prestimulus-onset (−0.6 to −0.1 s) and poststimulus-onset (0.5–1.2 s) time windows, plotted on a log-log scale. The dotted lines reflect the best linear fit to the log-transformed data (individual fits averaged across hemispheres). Box plots and individual data points show the slope of the best linear fit in the prestimulus and poststimulus time windows for the pmHG and alHG. B, Low-frequency (2–30 Hz) power spectrum after removal of the 1/f^χ component for the pmHG and alHG during the prestimulus and poststimulus time windows, plotted on a linear scale. Boxplots and individual data points show the power in the 7–10 Hz band in the prestimulus and poststimulus time windows for pmHG and alHG after removal of the 1/f^χ component. *p ≤ 0.05; n.s., not significant.