title: Neocortical grey matter distribution underlying voluntary, flexible vocalizations in chimpanzees.
abstract: Vocal learning is a key property of spoken language, which might also be present in nonhuman primate species, such as chimpanzees (Pan troglodytes), to a limited degree. While understanding the origins of vocal learning in the primate brain may help shed light on the evolution of speech and language, little is still known regarding the neurobiological correlates of vocal flexibility in nonhuman primates. The current study used voxel-based morphometry (VBM) to assess whether the cerebral cortex of captive chimpanzees that learned to voluntarily produce sounds to attract the attention of a human experimenter (attention-getting sounds) differs in grey matter distribution compared to chimpanzees that do not exhibit this behavior. It was found that chimpanzees that produce attention-getting sounds were characterized by increased grey matter in the ventrolateral prefrontal and dorsal premotor cortices. These findings suggest that the evolution of the capacity to flexibly modulate vocal output may be associated with reorganization of regions for motor control, including orofacial movements, in the primate brain.
authors.affiliation: Department of Anthropology, Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, D.C., USA.|Department of Neurology, Icahn School of Medicine, Mount Sinai, New York, NY, USA.
authors.forename: Serena
authors.initials: S
authors.lastname: Bianchi
authors.affiliation: Department of Anthropology, Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, D.C., USA.
authors.forename: Laura D
authors.initials: LD
authors.lastname: Reyes
authors.affiliation: Neuroscience Institute, Georgia State University, Atlanta, GA, USA.
authors.forename: William D
authors.initials: WD
authors.lastname: Hopkins
authors.affiliation: Department of Ecology, Evolution and Organismal Biology, Kennesaw University, Kennesaw, GA, USA.
authors.forename: Jared P
authors.initials: JP
authors.lastname: Taglialatela
authors.affiliation: Department of Anthropology, Center for the Advanced Study of Human Paleobiology, The George Washington University, Washington, D.C., USA.
authors.forename: Chet C
authors.initials: CC
authors.lastname: Sherwood
mesh_terms: D000818:Animals; D005260:Female; D066128:Gray Matter / Q000000981:diagnostic imaging*; D007858:Learning; D008279:Magnetic Resonance Imaging; D008297:Male; D019579:Neocortex / Q000000981:diagnostic imaging*; D002679:Pan troglodytes / Q000502:physiology*; D014828:Vocalization, Animal