Reliability of magnetoencephalography beta desynchronization for language lateralization in a subsequent memory...

Objective: Verb generation is associated with significant lateralized beta desynchronization in language but also motor related areas. Subsequent Memory Effect (SME) paradigms comprise receptive language and memory tasks. The current study examined whether lateralized beta patterns in language and/or motor related areas can be obtained with the receptive SME paradigm. Methods: MEG was recorded in 20 healthy right-handed adults during encoding and recognition phases of a word SME task. Measurements were repeated after 7-10 days to assess reliability. Post-stimulus beta (13-35 Hz) decrease was analyzed, and lateralization indices (LI > 0.1 indicating left dominance) were evaluated. Regions of interest (ROI) included IFG pars opercularis and triangularis (IFGO, IFGT), supramarginal gyrus, angular gyrus, superior temporal gyrus, and precentral gyrus (PreCG). An exploratory analysis included additional AAL regions. Results: Significant beta desynchronization within the ROIs was observed in 65-90% of participants. Lateralization was successful in up to 79% in the IFGT during encoding, 76% during recognition and 100% in the IFGO in encoding-recognition concordant cases. Exploratory analyses showed strong left lateralization in frontal, temporal and especially parietal areas. Initial reliability was limited, yet within-session concordance showed robust dominance with up to 100% concordance. Significant lateralized beta desynchronization was observed in the PreCG in 70-90% of participants. Conclusion: The SME paradigm shows promise in healthy participants, warranting investigation in patients with atypical language organization. Significance: Language related beta desynchronization is also observed in a receptive SME-task. Lateralized beta desynchronization in motor areas however suggest their contribution in verbal working memory and semantic control.