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Functionally homologous representation of vocalizations in the auditory cortex of humans and macaques.

ABSTRACT: How the evolution of speech has transformed the human auditory cortex compared to other primates remains largely unknown. While primary auditory cortex is organized largely similarly in humans and macaques,¹ the picture is much less clear at higher levels of the anterior auditory pathway,² particularly regarding the processing of conspecific vocalizations (CVs). A "voice region" similar to the human voice-selective areas³^,⁴ has been identified in the macaque right anterior temporal lobe with functional MRI;⁵ however, its anatomical localization, seemingly inconsistent with that of the human temporal voice areas (TVAs), has suggested a "repositioning of the voice area" in recent human evolution.⁶ Here we report a functional homology in the cerebral processing of vocalizations by macaques and humans, using comparative fMRI and a condition-rich auditory stimulation paradigm. We find that the anterior temporal lobe of both species possesses cortical voice areas that are bilateral and not only prefer conspecific vocalizations but also implement a representational geometry categorizing them apart from all other sounds in a species-specific but homologous manner. These results reveal a more similar functional organization of higher-level auditory cortex in macaques and humans than currently known.

SUBMITTER: Bodin C

PROVIDER: S-EPMC8585503 | biostudies-literature |

REPOSITORIES: biostudies-literature

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