Qinyao Sun1  · Shunli Zhu1  · Futing Yang2,3 · Zhigang Chen2,3 · Heling Li2,3 · Heng Shao4  · Hong Wang2,3 · Sangma Xie5  · Jiaojian Wang2,3

1 School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 625014, China 

2 State Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, China 

3 Yunnan Key Laboratory of Primate Biomedical Research, Kunming 650500, China 

4 Department of Geriatrics, The First People’s Hospital of Yunnan Province, The Afliated Hospital of Kunming University of Science and Technology, Kunming 650032, China 

5 Institute of Biomedical Engineering and Instrumentation, Hangzhou Dianzi University, Hangzhou 310018, China

Abstract

The temporal pole (TP), one of the most expanded cortical regions in humans relative to other primates, plays a crucial role in human language processing. It is also one of the most structurally and functionally asymmetric regions. However, whether the functional architecture of the TP is shared by humans and macaques is an open question. We used spectral clustering algorithms to define a cross-species fine-grained TP atlas with different anatomical connectivity patterns. We identified three similar subregions, two ventral and one dorsal, within the TP in both humans and macaques. The parcellation scheme for the TP was validated using functional gradient mapping, anatomical connectivity and resting-state functional connectivity pattern analysis, and functional characterization. Furthermore, in conjunction with the Allen Human Brain Atlas, we revealed the molecular basis for the functional connectivity patterns of each human TP subregion. In addition, we compared the hemispheric asymmetry in mean gray matter volume, anatomical connectivity fingerprints, and whole brain functional connectivity patterns to reveal the evolutionary differences in the TP and found different asymmetric patterns between humans and macaques. In conclusion, our findings reveal that the asymmetry in structure and connectivity may underpin the hemispheric functional specialization of the brain and provide a novel insight into understanding the evolutionary origin of the TP.

Keywords

Temporal pole; Parcellation; Asymmetry; Evolution; Human; Macaque

[SpringerLink]