Local and large-scale beta oscillatory dysfunction in males with mild traumatic brain injury.

Mild traumatic brain injury (mTBI) is impossible to detect using standard neuroradiological assessment such as structural magnetic resonance imaging (MRI). Injury does however disrupt the dynamic repertoire of neural activity indexed by neural oscillations. In particular, beta oscillations are reliable predictors of cognitive, perceptual and motor system functioning, as well as correlate highly with underlying myelin architecture and brain connectivity - all factors particularly susceptible to dysregulation after mTBI.

METHODS: We measured local and large-scale neural circuit function using MEG (magnetoencephalography) with a data-driven model fit approach using the Fitting Oscillations & One-Over F algorithm, in a group of young adult males with mTBI and a matched healthy control group. We quantified band-limited regional power and functional connectivity between brain regions.

RESULTS: We found reduced regional power and deficits in functional connectivity across brain areas, which pointed to the well-characterized thalamocortical dysconnectivity associated with mTBI. Furthermore, our results suggested beta functional connectivity data reached the best mTBI classification performance when compared with regional power and symptom severity (measured using SCAT2, or Sport Concussion Assessment Tool 2).

CONCLUSIONS: The current study revealed the relevance of beta oscillations as a window into neurophysiological dysfunction in mTBI, and also highlights the reliability of neural synchrony biomarkers in disorder classification.