Modelling the developmental lateralization of MEG event-related beta oscillations during auditory verb generation

Poster Session A - Saturday, April 13, 2024, 2:30 – 4:30 pm EDT, Sheraton Hall ABC

Minarose Ismail^1,2 (minaroseismail@gmail.com), Davide Momi³, Zheng Wang³, Cathy L. Barr^1,2, Anthony R. McIntosh⁴, Darren S. Kadis^1,2, John D. Griffiths^1,3; ¹University of Toronto, ²The Hospital for Sick Children, Toronto, ³Centre for Addiction and Mental Health, Toronto, ⁴Simon Fraser University, Vancouver

In adults performing verb generation in magnetoencephalography (MEG), we observe a distinct pattern of left-lateralized event-related desynchrony (ERD) and right-lateralized event-related synchrony (ERS) in the low beta band (13-23 Hz). In young children, low beta ERD and ERS are distributed bilaterally, with lateralization by adolescence. In this study, we investigate the developmental lateralization of these task-related oscillatory changes to unravel the neural mechanisms governing language hemispheric dominance. Utilizing the Whole-Brain Modelling in PyTorch (WhoBPyt) library (github.com/griffithslab/whobpyt), we fit individual connectome-based neural mass models, constructed from multi-shell diffusion-weighted MRI tractography, with trial-averaged MEG time series representing the early (-100-400ms) auditory evoked response in a verb generation task. Fitted brain network models accurately replicated the individual temporal dynamics of sensory-evoked activity in young children (4-7 years old; n=12) and adolescents (15-18 years old; n=10). Individual models were then used to simulate 1200ms epochs, and power spectral densities (PSDs) were computed using Welch’s method for the 700-1200ms time window that, critically, was not used for fitting. Notably, adolescent models predicted the late (700-1200ms) lateralized beta oscillatory responses in language-related high-order regions observed in the empirical data. Our findings suggest that language hemispheric dominance is encoded in the interaction between the structure and the dynamics of early sensory responses to language stimuli that predicts the lateralization of late event-related beta oscillations.

Topic Area: LANGUAGE: Development & aging