Sagittal slices of group activation patterns and contrast maps.

<p>Columns 1 to 4 show areas of activity across brain stem and cervical spinal cord before (1^st and 2^nd column) and after (3^rd and 4^th column) sensitization with the heat capsaicin model representing the significance (T-value) of each active voxel across the 16 subjects. Columns 5 and 6 show partial-least squares (PLS) results of contrast calculations on a voxel-by-voxel basis. The left column of each 2 columns (e.g. 1^st, 3^rd and 5^th) corresponds to the ipsilateral side of the stimulus, the right column to the contralateral side. The color bar on the right indicates the corresponding significance, i.e. T-value (columns 1–4) or bootstrap-ratio (columns 5–6) for each color.