Voice patches in the marmoset auditory cortex revealed by multimodal optical imaging

Species-specific vocalizations (including human voices) are important for the survival and social interactions of both humans and animals. In both humans and nonhuman primates, voice/vocalization-selective regions have been identified on the lateral temporal cortex. Here, we provide evidence of localized and hierarchically organized voice patches in the auditory cortex of the common marmoset, a highly vocal New World primate, using multimodal optical imaging techniques that directly measure activity from the smooth cortical surface in a noise-controlled environment. Both intrinsic imaging and calcium imaging data revealed two discrete voice patches in a region of the auditory cortex. Our results provided precise functional localization of the two voice patches (posterior and anterior) by anchoring their positions to the tonotopic map and core/noncore areas of the auditory cortex. Both patches preferentially respond to marmoset vocalizations, exhibit quantifiable neural selectivity beyond spectral features, and encode call type and caller identity. Distinct response properties reveal functional differentiation between the posterior and anterior voice patches, with latency differences consistent with a hierarchical relationship. These findings provide new evidence for an evolutionarily conserved cortical architecture in primates that supports vocal communication via voice patches, analogous to face processing systems in human and nonhuman primate brains.