The Relationship between White Matter Architecture and Language Lateralization in the Healthy Brain

Andrulyte, Ieva, De Bezenac, Christophe, Branzi, Francesca ORCID: 0000-0002-3780-9693, Forkel, Stephanie J, Taylor, Peter N and Keller, Simon S ORCID: 0000-0001-5247-9795 (2024) The Relationship between White Matter Architecture and Language Lateralization in the Healthy Brain JOURNAL OF NEUROSCIENCE, 44 (50). e0166242024-. ISSN 0270-6474, 1529-2401

Access the full-text of this item by clicking on the Open Access link.

Abstract

Interhemispheric anatomical differences have long been thought to be related to language lateralization. Previous studies have explored whether asymmetries in the diffusion characteristics of white matter language tracts are consistent with language lateralization. These studies, typically with smaller cohorts, yielded mixed results. This study investigated whether connectomic analysis of quantitative anisotropy (QA) and shape features of white matter tracts across the whole brain are associated with language lateralization. We analyzed 1,040 healthy individuals (562 females) from the Human Connectome Project database. Hemispheric language dominance for each participant was quantified using a laterality quotient (LQ) derived from fMRI activation in regions of interest (ROIs) associated with a language comprehension task compared against a math task. A linear regression model was used to examine the relationship between structural asymmetry and functional lateralization. Connectometry revealed a significant negative correlation between LQs and QA of corpus callosum tracts, indicating that higher QA in these regions is associated with bilateral and right hemisphere language representation in frontal and temporal regions. Left language laterality in the temporal lobe was significantly associated with longer right inferior fronto-occipital fasciculus (IFOF) and forceps minor tracts. These results suggest that diffusion measures of microstructural architecture as well as geometrical features of reconstructed white matter tracts play a role in language lateralization. People with increased dependence on the right or both frontal hemispheres for language processing may have more developed commissural fibers, which may support more efficient interhemispheric communication.

Item Type:	Article
Uncontrolled Keywords:	connectometry, corpus callosum, forceps minor, hemispheric asymmetries, language lateralization, MRI, tractography, white matter asymmetries
Divisions:	Faculty of Health & Life Sciences Faculty of Health & Life Sciences > Inst. Population Health
Depositing User:	Symplectic Admin
Date Deposited:	14 Oct 2024 07:28
Last Modified:	16 Jun 2026 20:03
DOI:	10.1523/JNEUROSCI.0166-24.2024
Open Access URL:	https://doi.org/10.1523/JNEUROSCI.0166-24.2024
Related Websites:	Author Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3185051
Disclaimer:	The University of Liverpool is not responsible for content contained on other websites from links within repository metadata. Please contact us if you notice anything that appears incorrect or inappropriate.