title: Migration Pathways of Thalamic Neurons and Development of Thalamocortical Connections in Humans Revealed by Diffusion MR Tractography.
abstract: The thalamus plays an important role in signal relays in the brain, with thalamocortical (TC) neuronal pathways linked to various sensory/cognitive functions. In this study, we aimed to see fetal and postnatal development of the thalamus including neuronal migration to the thalamus and the emergence/maturation of the TC pathways. Pathways from/to the thalami of human postmortem fetuses and in vivo subjects ranging from newborns to adults with no neurological histories were studied using high angular resolution diffusion MR imaging (HARDI) tractography. Pathways likely linked to neuronal migration from the ventricular zone and ganglionic eminence (GE) to the thalami were both successfully detected. Between the ventricular zone and thalami, more tractography pathways were found in anterior compared with posterior regions, which was well in agreement with postnatal observations that the anterior TC segment had more tract count and volume than the posterior segment. Three different pathways likely linked to neuronal migration from the GE to the thalami were detected. No hemispheric asymmetry of the TC pathways was quantitatively observed during development. These results suggest that HARDI tractography is useful to identify multiple differential neuronal migration pathways in human brains, and regional differences in brain development in fetal ages persisted in postnatal development.
authors.affiliation: Department of Behavioral Neuroscience, Northeastern University, Boston, MA 02115, USA.
authors.forename: Molly
authors.initials: M
authors.lastname: Wilkinson
authors.affiliation: Department of Behavioral Neuroscience, Northeastern University, Boston, MA 02115, USA.|Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
authors.forename: Tara
authors.initials: T
authors.lastname: Kane
authors.affiliation: Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.|Department of Radiology, Guizhou Provincial People's Hospital, 83 Zhong Shan Dong Lu, Guiyang, Guizhou Province 550002, P.R. China.
authors.forename: Rongpin
authors.initials: R
authors.lastname: Wang
authors.affiliation: Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.|Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02219, USA.
authors.forename: Emi
authors.initials: E
authors.lastname: Takahashi
mesh_terms: D000293:Adolescent; D000328:Adult; D002465:Cell Movement; D002648:Child; D002675:Child, Preschool; D038524:Diffusion Magnetic Resonance Imaging; D056324:Diffusion Tensor Imaging; D006801:Humans; D021621:Imaging, Three-Dimensional; D007223:Infant; D007231:Infant, Newborn; D009434:Neural Pathways / Q000166:cytology / Q000000981:diagnostic imaging / Q000254:growth & development; D009474:Neurons / Q000166:cytology*; D013788:Thalamus / Q000166:cytology* / Q000000981:diagnostic imaging / Q000254:growth & development*; D055815:Young Adult
keywords: brain; development; diffusion imaging; human; neuronal migration; thalamocortical; tractography; white matter