Cortical landmarks. (2A) A cytochrome oxidase stained tangential cortex section with locations of landmarks indicated in V1, S1, and A1. For V1 and S1, medial-, lateral-, and rostral-most corners were used. For A1, the centroid of the bounded region was used. (2B) For the PMBSF (inset), the centroid of each drawn barrel was used. Rostral is down, lateral is right.