al, 1984 [56]). As this region (area F5) corresponds to human area 44 (the inferior frontal cortex) as judged through comparative architectonic analysis (Petrides and Pandya, 1994 [57]), the NB might be related to Broca’s area, so it is not only the function but also the position of NB that changes between macaque and human. The present study suggests that the well-developed human NB might be related to language via its connections with Broca’s area 44 (the inferior frontal cortex) and the well-developed ventral half of the cerebellar dentate nucleus (see Fig. 15), the latter which is developed more greatly than the ape’s ventral half of the cerebellar dentate nucleus (see Matano, 2001 [58]). A recent diffusion tensor tractography study using MRI demonstrated that the human red nucleus receives strong projections from the prefrontal cortex (Habas and Cabanis, 2006 [59]). 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