Anatomy of nerve fiber bundles at micrometer-resolution in the vervet monkey visual system
- National Institute of Information and Communications Technology, Japan
- Research Centre Jülich, Germany
- Wake Forest School of Medicine, United States
- University of California, Los Angeles, United States
Abstract
Although the primate visual system has been extensively studied, detailed spatial organization of white matter fiber tracts carrying visual information between areas has not been fully established. This is mainly due to the large gap between tracer studies and diffusion-weighted MRI studies, which focus on specific axonal connections and macroscale organization of fiber tracts, respectively. Here we used 3D polarization light imaging (3D-PLI), which enables direct visualization of fiber tracts at micrometer resolution, to identify and visualize fiber tracts of the visual system, such as stratum sagittale, inferior longitudinal fascicle, vertical occipital fascicle, tapetum and dorsal occipital bundle in vervet monkey brains. Moreover, 3D-PLI data provide detailed information on cortical projections of these tracts, distinction between neighboring tracts, and novel short-range pathways. This work provides essential information for interpretation of functional and diffusion-weighted MRI data, as well as revision of wiring diagrams based upon observations in the vervet visual system.
Data availability
Original data is publicly available via the EBRAINS platform of the Human Brain Project (Axer et al., 2020; DOI: 10.25493/AFR3-KDK).
Article and author information
Author details
Nicola Palomero-Gallagher
Funding
Japan Society for the Promotion of Science (JP17H04684)
- Hiromasa Takemura
Japan Society for the Promotion of Science (JP15J00412)
- Hiromasa Takemura
European Union's Horizon 2020 Research and Innovation Programme (785907 (HBP SGA2))
- Markus Axer
- Karl Zilles
National Institutes of Health (R01 MH092311)
- Roger Woods
P40 grant (OD010965)
- Matthew J Jorgensen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Vervet monkeys (Chlorocebus aethiops sabaeus) used in this study were part of the Vervet Research Colony and were housed at the Wake Forest School of Medicine. Macaque monkeys (Macaca fascicularis) were obtained from Covance (Münster, Germany). Animals were colony-born, of known age and were mother-reared in species-typical social groups. The present study did not include experimental procedures with live animals. Brains were obtained when animals were sacrificed to reduce the size of the colony, where they were maintained in accordance with the guidelines of the Directive 2010/63/eu of the European Parliament and of the Council on the protection of animals used for scientific purposes or the Wake Forest Institutional Animal Care and Use Committee IACUC #A11-219. Euthanasia procedures conformed to the AVMA Guidelines for the Euthanasia of Animals.
Copyright
© 2020, Takemura 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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Anatomy of nerve fiber bundles at micrometer-resolution in the vervet monkey visual system
eLife 9:e55444.
https://doi.org/10.7554/eLife.55444
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