Fig. 5
Whole-brain searchlight representational similarity analysis (RSA) of multi-voxel category, value, and saliency signals. a Schematic illustration of the procedure of the whole-brain searchlight RSA. In this analysis, activation patterns in the immediate neighborhood of every voxel (a 27-voxel cube with that voxel as the center) was examined. The construction of searchlight neural representational dissimilarity matrices (neural RDMs) from multi-voxel activity patterns in response to each condition in the paradigm was based on Pearson correlational distance. The neural RDMs were then compared with candidate model RDMs based on different hypotheses. Example theoretical candidate similarity matrices based on category identity, value, and saliency are shown. The latter two candidate matrices depended on pleasantness ratings and, therefore, differed between participants. The candidate matrices from one representative participant are shown here. b–d Whole-brain maps of the z-statistic of the resemblance between the neural RDMs and each of the candidate RDMs, including category b, value c, and saliency d. Statistical thresholds for all maps were per-voxel p < 0.005 and cluster-size thresholding at FWE p < 0.05. The human brain image in a, entitled “human brain on white background”, by _DJ_ is sourced from https://www.flickr.com/photos/flamephoenix1991/8376271918 and licensed under CC BY 2.0 (https://creativecommons.org/licenses/by-sa/2.0/)
