Martin Bech
Universitetslektor
Axon morphology is modulated by the local environment and impacts the noninvasive investigation of its structure-function relationship
Författare
Summary, in English
Axonal conduction velocity, which ensures efficient function of the brain network, is related to axon diameter. Noninvasive, in vivo axon diameter estimates can be made with diffusion magnetic resonance imaging, but the technique requires three-dimensional (3D) validation. Here, high-resolution, 3D synchrotron X-ray nano-holotomography images of white matter samples from the corpus callosum of a monkey brain reveal that blood vessels, cells, and vacuoles affect axonal diameter and trajectory. Within single axons, we find that the variation in diameter and conduction velocity correlates with the mean diameter, contesting the value of precise diameter determination in larger axons. These complex 3D axon morphologies drive previously reported 2D trends in axon diameter and g-ratio. Furthermore, we find that these morphologies bias the estimates of axon diameter with diffusion magnetic resonance imaging and, ultimately, impact the investigation and formulation of the axon structure-function relationship.
Avdelning/ar
- X-ray Phase Contrast
Publiceringsår
2020
Språk
Engelska
Sidor
33649-33659
Publikation/Tidskrift/Serie
Proceedings of the National Academy of Sciences of the United States of America
Volym
117
Issue
52
Dokumenttyp
Artikel i tidskrift
Förlag
National Academy of Sciences
Ämne
- Radiology, Nuclear Medicine and Medical Imaging
- Other Physics Topics
Nyckelord
- axon morphology
- brain
- conduction velocity
- MRI
- myelination
Status
Published
Forskningsgrupp
- X-ray Phase Contrast
ISBN/ISSN/Övrigt
- ISSN: 1091-6490