Graphs obtained from OIS data in the anterior and posterior SII cortical regions evoked by flutter stimulus on the central pad of 2 subjects. Figurines indicate regions of interest. (A) Top Panels: Time course of absorbance values from the posterior SII region obtained with ipsilateral, contralateral, and bilateral stimulus. Note that in this case, the absorbance evoked by the bilateral stimulus is larger than the response evoked by either the ipsilateral or the contralateral stimulus. (B) Bottom Panels: Time course of absorbance values from the anterior SII region obtained from data sampled during ipsilateral, contralateral, and bilateral stimulation. Note that the response evoked by the bilateral stimulus is smaller than the response evoked by the contralateral stimulus. Maximal differentiation of the time course of the response to the different stimulus conditions appears to occur between 1 and 3 seconds.