AUTHOR=Xia Xiaoluan , Fan Lingzhong , Cheng Chen , Yao Rong , Deng HongXia , Zhao Dongqin , Li Haifang , Jiang Tianzi 

TITLE=Interspecies Differences in the Connectivity of Ventral Striatal Components Between Humans and Macaques

JOURNAL=Frontiers in Neuroscience

VOLUME=Volume 13 - 2019

YEAR=2019

URL=https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2019.00623

DOI=10.3389/fnins.2019.00623

ISSN=1662-453X

ABSTRACT=Although the evolutionarily conserved functions of the ventral striatal components have been used as a priori knowledge for further studies, whether these functions are conserved between species remains unclear. In particular, whether macroscopic connectivity supports this given the disproportionate volumetric differences between species in the brain regions that project to the ventral striatum, including the prefrontal and limbic areas, has not been established. The evolutionarily conserved functions of the ventral striatal components have been suggested and used as a priori knowledge for further studies. However, whether this hypothesis is supported by macroscopic connectivity remains unclear, especially when considering the disproportionate volumetric differences between species in the brain regions known to project to the ventral striatum, including the prefrontal and limbic areas. In this study, the human and macaque striatum was first tractographically parcellated to define the ventral striatum and its two subregions, the nucleus accumbens (Acb)-like and the neurochemically unique domains of the Acb and putamen (NUDAPs)-like divisions. Our results revealed a similar topographical distribution of the connectivity-based ventral striatal components in the two primate brains. Successively, a set of targets was extracted to construct a connectivity fingerprint to characterize these parcellation results, enabling cross-species comparisons. Our results indicated that the connectivity fingerprints of the ventral striatum-like divisions were dissimilar in the two species. We localized this difference to specific targets to analyze possible interspecies functional modifications. Our results also revealed interspecies-convergent connectivity ratio fingerprints of the target group to these two ventral striatum-like subregions. This convergence may suggest synchronous connectional changes of these ventral striatal components during primate evolution.