Open AccessAge of acquisition impacts the brain differently depending on neuroanatomical metric
Author(s) -
ClausseniusKalman Hannah,
Vaughn Kelly A.,
ArchilaSuerte Pilar,
Hernandez Arturo E.
Publication year - 2020
Publication title -
human brain mapping
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.005
H-Index - 191
eISSN - 1097-0193
pISSN - 1065-9471
DOI - 10.1002/hbm.24817
Subject(s) - supramarginal gyrus , psychology , neuroscience of multilingualism , age of acquisition , cognition , neuroscience , middle temporal gyrus , cognitive psychology , brain size , superior temporal gyrus , angular gyrus , developmental psychology , functional magnetic resonance imaging , medicine , magnetic resonance imaging , radiology
Although researchers generally agree that a certain set of brain areas underlie bilingual language processing, there is discrepancy regarding what effect timing of language acquisition has on these regions. We aimed to investigate the neuroanatomical correlates of age of acquisition (AoA), which has been examined previously, but with inconsistent results, likely influenced by methodological differences across studies. We analyzed gray matter density, volume, and thickness using whole‐brain linear models in 334 bilinguals and monolinguals. Neuroanatomical correlates of AoA differed depending on gray matter metric. Relative to early bilinguals, late bilinguals had thicker cortex in language processing and cognitive control regions, and greater density in multiple frontal areas and the right middle temporal and supramarginal gyri. Early bilinguals had greater volume than late bilinguals in the left middle temporal gyrus. Overall, volume was the least sensitive to AoA‐related differences. Multiple regions not classically implicated in dual‐language processing were also found, which highlights the important role of whole‐brain analyses in neuroscience. This is the first study to investigate AoA and gray matter thickness, volume, and density all in the same sample. We conclude that cognitive models of bilingualism should consider the roles of development and neuroanatomical metric in driving our understanding of bilingual and monolingual language organization.