Mapping the human subcortical auditory system using histology, post mortem MRI and in vivo MRI at 7T
- Massachusetts Institute of Technology, United States
- Maastricht University, Netherlands
- Duke University, United States
Abstract
Studying the human subcortical auditory system non-invasively is challenging due to its small, densely packed structures deep within the brain. Additionally, the elaborate three-dimensional (3-D) structure of the system can be difficult to understand based on currently available 2-D schematics and animal models. We addressed these issues using a combination of histological data, post mortem magnetic resonance imaging (MRI), and in vivo MRI at 7 Tesla. We created anatomical atlases based on state-of-the-art human histology (BigBrain) and post mortem MRI (50 μm). We measured functional MRI (fMRI) responses to natural sounds and demonstrate that the functional localization of subcortical structures is reliable within individual participants who were scanned in two different experiments. Further, a group functional atlas derived from the functional data locates these structures with a median distance below 2mm. Using diffusion MRI tractography, we revealed structural connectivity maps of the human subcortical auditory pathway both in vivo (1050 μm isotropic resolution) and post mortem (200 μm isotropic resolution). This work captures current MRI capabilities for investigating the human subcortical auditory system, describes challenges that remain, and contributes novel, openly available data, atlases, and tools for researching the human auditory system.
Data availability
In vivo data are available on OpenNeuro: https://openneuro.org/datasets/ds001942Derivatives (including histology-based, post mortem MRI-based, and fMRI-based atlases) are available on the Open Science Framework: https://osf.io/c4m82/Analysis code, flowcharts, and other auxiliary files are available on Github: https://github.com/sitek/subcortical-auditory-atlas
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Mapping the human subcortical auditory systemOpen Science Framework, DOI 10.17605/OSF.IO/HXEKN.
Article and author information
Author details
Funding
NWO (864-13-012)
- Omer Faruk Gulban
- Federico de Martino
National Institutes of Health (5R01EB020740)
- Satrajit S Ghosh
National Institutes of Health (P41EB019936)
- Satrajit S Ghosh
National Institutes of Health (5F31DC015695)
- Kevin R Sitek
Eaton Peabody Laboratory at Mass Eye and Ear (Amelia Peabody Scholarship)
- Kevin R Sitek
Harvard Brain Science Initiative (Travel Grant)
- Kevin R Sitek
National Institutes of Health (P41EB015897)
- G Allan Johnson
National Institutes of Health (1S10OD010683-01)
- G Allan Johnson
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: The experimental procedures were approved by the ethics committee of the Faculty for Psychology and Neuroscience at Maastricht University (reference number: ERCPN-167_09_05_2016), and were performed in accordance with the approved guidelines and the Declaration of Helsinki. Written informed consent was obtained for every participant before conducting the experiments. All participants reported to have normal hearing, had no history of hearing disorder/impairments or neurological disease.
Copyright
© 2019, Sitek 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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Mapping the human subcortical auditory system using histology, post mortem MRI and in vivo MRI at 7T
eLife 8:e48932.
https://doi.org/10.7554/eLife.48932
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