PMC

Aligned Aδ (laser) and Aβ (air puffs) maps for a single subject (subject 5, dorsolateral view).

Surface-based average Aδ (laser) and Aβ (air puffs) maps from seven subjects (dorsolateral view). The complex-valued mapping data were averaged in a spherical surface coordinate system after morphing each subject's data into alignment with an average spherical sulcal pattern, and the F-statistics was rendered back onto the unfolded cortical surface of one subject.

Map locations in spherical and Talairach space. For each subject, the central sulcus was identified and the location of the centroid of Aδ (laser) and Aβ (air puffs) maps was rendered onto a plane tangential to the morphed spherical surface. In addition, the centroids of the average maps of 7 subjects, taken from , were displayed for comparison (see Materials and Methods for details). The centroids were plotted both in spherical space relative to the central sulcus, and in Talairach space ().

a, Phase-encoded protocol and raw BOLD response in one voxel. The color coding scheme used for Aδ (laser) and Aβ (air puffs) maps in – is shown in a. b, Aligned Aδ (laser) and Aβ (air puffs) maps for a single subject (subject 2, dorsolateral view). Thick dashed white contours outline a region of interest defined as the connected surface patch of SI vertices with significant periodic response to both Aδ and Aβ stimulation. A similar alignment is evident for every color, representing stimulation to the digits (d2–d5). The alignment index histogram shows the distribution of agreement in phase angle for each surface vertex within the dashed contour (1 = max alignment). The red line indicates the distribution of the alignment index that would be expected if the two maps were completely uncorrelated. c, Location of the two maps (red cross) in an illustrative single subject.