New insights in the homotopic and heterotopic connectivity of the frontal portion of the human corpus callosum revealed by microdissection and diffusion tractography - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Human Brain Mapping Année : 2016

New insights in the homotopic and heterotopic connectivity of the frontal portion of the human corpus callosum revealed by microdissection and diffusion tractography

Laurent Petit

Résumé

Extensive studies revealed that the human corpus callosum (CC) plays a crucial role in providing large–scale bi-hemispheric integration of sensory, motor and cognitive processing, especially within the frontal lobe. However, the literature lacks of conclusive data regarding the structural macroscopic connectivity of the frontal CC. In this study, a novel microdissection approach was adopted, to expose the frontal fibers of CC from the dorsum to the lateral cortex in eight hemispheres and in one entire brain. Post-mortem results were then combined with data from advanced constrained spherical deconvolution in 130 healthy subjects. We demonstrated as the frontal CC provides dense inter-hemispheric connections. In particular, we found three types of fronto-callosal fibers, having a dorso-ventral organization. First, the dorso-medial CC fibers subserve homotopic connections between the homologous medial cortices of the superior frontal gyrus. Second, the ventro-lateral CC fibers subserve homotopic connections between lateral frontal cortices, including both the middle frontal gyrus and the inferior frontal gyrus, as well as heterotopic connections between the medial and lateral frontal cortices. Third, the ventro-striatal CC fibers connect the medial and lateral frontal cortices with the contralateral putamen and caudate nucleus. We also highlighted an intricate crossing of CC fibers with the main association pathways terminating in the lateral regions of the frontal lobes. This combined approach of ex vivo microdissection and in vivo diffusion tractography allowed demonstrating a previously unappreciated three-dimensional architecture of the anterior frontal CC, thus clarifying the functional role of the CC in mediating the inter-hemispheric connectivity.
Fichier principal
Vignette du fichier
10936_DeBenedictis_HBM_inpress_16.pdf (1.49 Mo) Télécharger le fichier
Origine : Fichiers éditeurs autorisés sur une archive ouverte

Dates et versions

hal-01382512 , version 1 (26-01-2021)

Identifiants

Citer

Alessandro de Benedictis, Laurent Petit, Maxime Descoteaux, Carlo Efisio Marras, Mattia Barbareschi, et al.. New insights in the homotopic and heterotopic connectivity of the frontal portion of the human corpus callosum revealed by microdissection and diffusion tractography. Human Brain Mapping, 2016, 37 (12), pp.4718-4735. ⟨10.1002/hbm.23339⟩. ⟨hal-01382512⟩
75 Consultations
58 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More