title: Developmental patterns of expressive language hemispheric lateralization in children, adolescents and adults using functional near-infrared spectroscopy.
abstract: The development of language hemispheric specialization is not well understood in young children, especially regarding expressive language functions. In this study, we investigated age-related changes in expressive language lateralization patterns in a population of children (3-6 and 7-10 years old), adolescents (11-16 years old), and young adults (19-30 years old). During functional near-infrared spectroscopy recordings, all participants performed a verbal fluency task, which consisted in naming as many words as possible belonging to a given semantic category. Hemoglobin concentration changes were measured in bilateral frontal and temporal cortical areas. During the language task, results showed a strong left hemisphere response along with weaker right hemisphere activation in all groups. Age-related increases in hemodynamic responses were found bilaterally, with younger children showing smaller hemodynamic responses than adolescents and adults in both hemispheres. Overall, these findings confirm that a left hemisphere specialization is already established in young children and persists through adulthood. Early left hemisphere specialization for expressive language suggests that language development hinges on structural and functional properties of the human brain with little reorganization occurring with development.
authors.affiliation: Sainte-Justine University Hospital Research Center, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC, Canada H3T 1C5; Centre de Recherche en Neuropsychologie et Cognition, Université de Montréal, P.O. Box 6128, Downtown Station, Montreal, QC, Canada H3C 3J7.
authors.forename: Natacha
authors.initials: N
authors.lastname: Paquette
authors.affiliation: Sainte-Justine University Hospital Research Center, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC, Canada H3T 1C5; Centre de Recherche en Neuropsychologie et Cognition, Université de Montréal, P.O. Box 6128, Downtown Station, Montreal, QC, Canada H3C 3J7.
authors.forename: Maryse
authors.initials: M
authors.lastname: Lassonde
authors.affiliation: Sainte-Justine University Hospital Research Center, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC, Canada H3T 1C5.
authors.forename: Phetsamone
authors.initials: P
authors.lastname: Vannasing
authors.affiliation: Sainte-Justine University Hospital Research Center, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC, Canada H3T 1C5.
authors.forename: Julie
authors.initials: J
authors.lastname: Tremblay
authors.affiliation: Sainte-Justine University Hospital Research Center, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC, Canada H3T 1C5; Centre de Recherche en Neuropsychologie et Cognition, Université de Montréal, P.O. Box 6128, Downtown Station, Montreal, QC, Canada H3C 3J7; Unidad de Investigación en Neurodesarrollo, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, CP 76230, Juriquilla, Querétaro, México.
authors.forename: Berta
authors.initials: B
authors.lastname: González-Frankenberger
authors.affiliation: Sainte-Justine University Hospital Research Center, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC, Canada H3T 1C5; Centre de Recherche en Neuropsychologie et Cognition, Université de Montréal, P.O. Box 6128, Downtown Station, Montreal, QC, Canada H3C 3J7.
authors.forename: Olivia
authors.initials: O
authors.lastname: Florea
authors.affiliation: Sainte-Justine University Hospital Research Center, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC, Canada H3T 1C5; Centre de Recherche en Neuropsychologie et Cognition, Université de Montréal, P.O. Box 6128, Downtown Station, Montreal, QC, Canada H3C 3J7.
authors.forename: Renée
authors.initials: R
authors.lastname: Béland
authors.affiliation: Sainte-Justine University Hospital Research Center, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC, Canada H3T 1C5; Centre de Recherche en Neuropsychologie et Cognition, Université de Montréal, P.O. Box 6128, Downtown Station, Montreal, QC, Canada H3C 3J7.
authors.forename: Franco
authors.initials: F
authors.lastname: Lepore
authors.affiliation: Sainte-Justine University Hospital Research Center, 3175 Chemin de la Côte-Sainte-Catherine, Montréal, QC, Canada H3T 1C5; Centre de Recherche en Neuropsychologie et Cognition, Université de Montréal, P.O. Box 6128, Downtown Station, Montreal, QC, Canada H3C 3J7. Electronic address: anne.gallagher@umontreal.ca.
authors.forename: Anne
authors.initials: A
authors.lastname: Gallagher
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005260:Female; D005625:Frontal Lobe / Q000254:growth & development / Q000502:physiology*; D007839:Functional Laterality / Q000502:physiology*; D059907:Functional Neuroimaging / Q000379:methods*; D006801:Humans; D007804:Language Development; D008297:Male; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D013702:Temporal Lobe / Q000254:growth & development / Q000502:physiology*; D055815:Young Adult
keywords: Children; Expressive language development; Hemispheric lateralization patterns; Near-infrared spectroscopy (Nirs); Optical imaging; Verbal fluency