Exploring the relationship between cerebellar asymmetry and handedness in chimpanzees (Pan troglodytes) and capuchins (Cebus apella)

A comparative study of chimpanzee (Pan troglodytes) and capuchin monkey (Cebus apella) cerebellar asymmetry and its relationship to handedness was conducted. Magnetic resonance images of the brain and behavioral data on a coordinated bimanual task were obtained from 16 chimpanzees and 11 capuchins. Chimpanzees displayed a greater rightward bias of the posterior cerebellum and capuchins displayed a greater leftward bias of the anterior cerebellum. Cerebellar asymmetries were significantly associated with handedness in capuchins but not chimpanzees, and this effect was most pronounced in right-handed capuchins.