Figure 2

Comparison of SI cortical responses evoked by low- and high-amplitude 25 Hz flutter stimuli in three additional subjects. Shown for each subject (A-C) are: (1) the stimulus location on the hand, (2) the average light absorbance images of the cortical optical response to the 50 μm- and 400 μm-amplitude stimuli, (3) the magnified 3-D activity maps of the region sampled, and (4) the power spectra of the OIS responses. All subjects exhibited similar differences between their low and high stimulus amplitude power spectra.