Cross-species cortical alignment identifies different types of anatomical reorganization in the primate temporal lobe
- University of Oxford, United Kingdom
- King's College London, United Kingdom
- Emory University, United States
- Radboud Universiteit, Netherlands
Abstract
Evolutionary adaptations of temporo-parietal cortex are considered to be a critical specialization of the human brain. Cortical adaptations, however, can affect different aspects of brain architecture, including local expansion of the cortical sheet or changes in connectivity between cortical areas. We distinguish different types of changes in brain architecture using a computational neuroanatomy approach. We investigate the extent to which between-species alignment, based on cortical myelin, can predict changes in connectivity patterns across macaque, chimpanzee, and human. We show that expansion and relocation of brain areas can predict terminations of several white matter tracts in temporo-parietal cortex, including the middle and superior longitudinal fasciculus, but not the arcuate fasciculus. This demonstrates that the arcuate fasciculus underwent additional evolutionary modifications affecting the temporal lobe connectivity pattern. This approach can flexibly be extended to include other features of cortical organization and other species, allowing direct tests of comparative hypotheses of brain organization.
Data availability
This study used previously published datasets and availability of source data for the different data sets is provided in an overview table in the main manuscript ('Data Availability Overview'). The anonymised human MRI dataset that was generated for the present study is available via OpenNeuro under the accession code ds002634 (version 1.0.1). The results scene files have been made available from the Wellcome Centre for Integrative Neuroimaging's GitLab at git.fmrib.ox.ac.uk/neichert/project_MSM. Group-level myelin-maps and tract surface maps of the three species will be openly accessible as part of the results scene files. Numerical data underlying Figure 5 and Appendix 3 - Figure 2 are provided as Source Data with the article. All further derived data supporting the findings of this study are available from the corresponding author upon request.
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National Chimpanzee Brain ResourceNational Chimpanzee Brain Resource. RRID: SCR_006863.
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University of Oxford WIN Macaque PMPRIMatE Data Exchange (PRIME-DE) resource. RRID: SCR_016621.
Article and author information
Author details
Funding
Wellcome (203730/Z/16/Z)
- Nicole Eichert
Marie Sklodowska-Curie Fellowship (750026)
- Katherine L Bryant
Medical Research Council (MR/L009013/1)
- Saad Jbabdi
National Institute for Health Research
- Mark Jenkinson
Oxford Biomedical Research Centre
- Mark Jenkinson
Biotechnology and Biological Sciences Research Council (BB/H016902/1)
- Kristine Krug
Wellcome (101092/Z/13/Z)
- Kristine Krug
Other (R01MH118534)
- Longchuan Li
Other (P50MH100029)
- Longchuan Li
Other (R01MH118285)
- Longchuan Li
Wellcome (203139/Z/16/Z)
- Rogier B Mars
NIHR Oxford Heath Biomedical Research Centre
- Rogier B Mars
Biotechnology and Biological Sciences Research Council (BB/N019814/1)
- Rogier B Mars
Netherlands Organization for Scientific Research (452-13-015)
- Rogier B Mars
Academy of Medical Sciences
- Emma C Robinson
British Heart Foundation
- Emma C Robinson
Government Department of Business, Energy and Industrial Strategy
- Emma C Robinson
Wellcome (SBF003\1116)
- Emma C Robinson
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Chimpanzee data:Data were acquired at the Yerkes National Primate Research Center (YNPRC) at Emory University through separate studies covered by animal research protocols approved by YNPRC and the Emory University Institutional Animal Care and Use Committee (approval no. YER-2001206). These chimpanzee MRI scans were obtained from a data archive of scans obtained prior to the 2015 implementation of U.S. Fish and Wildlife Service and National Institutes of Health regulations governing research with chimpanzees. All the scans reported in this publication were completed by the end of 2012.Macaque Data:Procedures of the in vivo macaque data acquisition were carried out in accordance with Home Office (UK) Regulations and European Union guidelines (EU directive 86/609/EEC; EU Directive 2010/63/EU).
Human subjects: The study was approved by the Central University (of Oxford) Research Ethics Committee (CUREC, R55787/RE001) in accordance with the regulatory standards of the Code of Ethics of the World Medical Association (Declaration of Helsinki). All participants gave informed consent to their participation and were monetarily compensated for their participation.
Copyright
© 2020, Eichert et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Cross-species cortical alignment identifies different types of anatomical reorganization in the primate temporal lobe
eLife 9:e53232.
https://doi.org/10.7554/eLife.53232
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