Analyzing functional, structural, and anatomical correlation of hemispheric language lateralization in healthy...

Area of Science:

• Neuroimaging
• Neuroscience
• Brain Mapping

Background:

• Assessing hemispheric language lateralization is crucial for understanding brain function.
• Noninvasive neuroimaging techniques offer promising avenues for this assessment.

Purpose of the Study:

• To evaluate the concordance of language lateralization using diffusion tensor imaging (DTI) and voxel-based morphometry (VBM) compared to functional magnetic resonance imaging (fMRI).
• To identify anatomical correlates for language lateralization determined by fMRI.

Main Methods:

• Fifty-seven healthy volunteers underwent language fMRI and 30 underwent DTI.
• Calculated fMRI laterality index (LI), DTI fiber tract asymmetry index (AI), and tract-based statistics.
• Correlated these measures with VBM volumetry of Heschl's gyrus, planum temporale, and insula.
• Linear regression analysis was used to assess correlations.

Main Results:

• Good agreement was observed between fMRI LI and DTI AI, particularly for the arcuate fasciculus and inferior longitudinal fasciculus.
• Significant correlations (P < 0.05) were found between BOLD fMRI activations, tract-based statistics, and planum temporale/Heschl's gyrus volumetry for language lateralization.

Conclusions:

• A strong one-to-one correlation exists between fMRI, DTI tractography, and VBM volumetry measures for determining language lateralization.
• These findings support the use of combined neuroimaging approaches for robust language lateralization assessment.