Diversity of Cortico-descending Projections: Histological and Diffusion MRI Characterization in the Monkey.

Details

Serval ID
serval:BIB_51A463519687
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Diversity of Cortico-descending Projections: Histological and Diffusion MRI Characterization in the Monkey.
Journal
Cerebral cortex
Author(s)
Innocenti G.M., Caminiti R., Rouiller E.M., Knott G., Dyrby T.B., Descoteaux M., Thiran J.P.
ISSN
1460-2199 (Electronic)
ISSN-L
1047-3211
Publication state
Published
Issued date
01/02/2019
Peer-reviewed
Oui
Volume
29
Number
2
Pages
788-801
Language
english
Notes
Publication types: Journal Article ; Research Support, Non-U.S. Gov't
Publication Status: ppublish
Abstract
The axonal composition of cortical projections originating in premotor, supplementary motor (SMA), primary motor (a4), somatosensory and parietal areas and descending towards the brain stem and spinal cord was characterized in the monkey with histological tract tracing, electron microscopy (EM) and diffusion MRI (dMRI). These 3 approaches provided complementary information. Histology provided accurate assessment of axonal diameters and size of synaptic boutons. dMRI revealed the topography of the projections (tractography), notably in the internal capsule. From measurements of axon diameters axonal conduction velocities were computed. Each area communicates with different diameter axons and this generates a hierarchy of conduction delays in this order: a4 (the shortest), SMA, premotor (F7), parietal, somatosensory, premotor F4 (the longest). We provide new interpretations for i) the well-known different anatomical and electrophysiological estimates of conduction velocity; ii) why conduction delays are probably an essential component of the cortical motor command; and iii) how histological and dMRI tractography can be integrated.
Keywords
Animals, Cercopithecus, Diffusion Magnetic Resonance Imaging/methods, Diffusion Tensor Imaging/methods, Macaca fascicularis, Macaca mulatta, Motor Cortex/chemistry, Motor Cortex/cytology, Motor Cortex/diagnostic imaging, Pyramidal Tracts/chemistry, Pyramidal Tracts/cytology, Pyramidal Tracts/diagnostic imaging
Pubmed
Web of science
Create date
03/03/2018 12:48
Last modification date
27/04/2020 5:20
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