Exploring the Early Organization and Maturation of Linguistic Pathways in the Human Infant Brain.
Linguistic processing is based on a close collaboration between temporal and frontal regions connected by two pathways: the "dorsal" and "ventral pathways" (assumed to support phonological and semantic processing, respectively, in adults). We investigated here the development of these pathways at the onset of language acquisition, during the first post-natal weeks, using cross-sectional diffusion imaging in 21 healthy infants (6-22 weeks of age) and 17 young adults. We compared the bundle organization and microstructure at these two ages using tractography and original clustering analyses of diffusion tensor imaging parameters. We observed structural similarities between both groups, especially concerning the dorsal/ventral pathway segregation and the arcuate fasciculus asymmetry. We further highlighted the developmental tempos of the linguistic bundles: The ventral pathway maturation was more advanced than the dorsal pathway maturation, but the latter catches up during the first post-natal months. Its fast development during this period might relate to the learning of speech cross-modal representations and to the first combinatorial analyses of the speech input.
INSERM, U992, Cognitive Neuroimaging Unit, Gif-sur-Yvette, France CEA, NeuroSpin Center, Gif-sur-Yvette, France University Paris Sud, Orsay, France.
Jessica
J
Dubois
CEA, NeuroSpin Center, UNIRS, Gif-sur-Yvette, France.
Cyril
C
Poupon
CEA, NeuroSpin Center, Gif-sur-Yvette, France University Paris Sud, Orsay, France INRIA, Parietal, Gif-sur-Yvette, France.
Bertrand
B
Thirion
INSERM, U992, Cognitive Neuroimaging Unit, Gif-sur-Yvette, France CEA, NeuroSpin Center, Gif-sur-Yvette, France University Paris Sud, Orsay, France.
Hina
H
Simonnet
INSERM, U1129, Paris, France CEA, NeuroSpin Center, UNIACT, Gif-sur-Yvette, France University Paris Descartes, Paris, France.
Sofya
S
Kulikova
INSERM, U992, Cognitive Neuroimaging Unit, Gif-sur-Yvette, France CEA, NeuroSpin Center, Gif-sur-Yvette, France University Paris Sud, Orsay, France.
François
F
Leroy
INSERM, U1129, Paris, France CEA, NeuroSpin Center, UNIACT, Gif-sur-Yvette, France University Paris Descartes, Paris, France.
Lucie
L
Hertz-Pannier
INSERM, U992, Cognitive Neuroimaging Unit, Gif-sur-Yvette, France CEA, NeuroSpin Center, Gif-sur-Yvette, France University Paris Sud, Orsay, France.
Ghislaine
G
Dehaene-Lambertz
D001921:Brain / Q000033:anatomy & histology* / Q000254:growth & development*; D003430:Cross-Sectional Studies; D038524:Diffusion Magnetic Resonance Imaging; D056324:Diffusion Tensor Imaging; D005260:Female; D005625:Frontal Lobe / Q000033:anatomy & histology / Q000196:embryology; D006801:Humans; D007223:Infant; D007804:Language Development; D008037:Linguistics; D008297:Male; D009434:Neural Pathways / Q000033:anatomy & histology / Q000254:growth & development; D013702:Temporal Lobe / Q000033:anatomy & histology / Q000196:embryology; D066127:White Matter / Q000033:anatomy & histology / Q000196:embryology
brain development; diffusion imaging; interhemispheric asymmetry; language network; white matter maturation and myelination