Figure 3.

Expansion of posterior brain regions. Human posterior brain regions in the parietotemporal regions have expanded considerably. (a) Comparison of the relative positions in macaque (left) and human (right) brains of landmark regions such as primary auditory cortex (A1) and the motion-sensitive area V5/MT reveals how the latter has shifted posteriorly and inferiorly in humans compared with its location in the depths of the superior temporal sulcus in macaque. (b) One way to map homologous regions in monkey and human brains is to compare connectivity of regions. The recent study by Rushworth et al. [59] demonstrates connections in the human parietal cortex from the superior colliculus (connected to area LIP within the IPS of macaque), ventral premotor cortex (connected to area 7b in macaque) and the parahippocampal region (connected to area 7a in macaque). But there is a region within the human IPL (marked within the white circle) that seems not to have connections to any of these regions and might be a candidate zone for a novel cortical region within the IPL. Panel b adapted from Ref. [59], with permission from Oxford University Press.