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bioRxiv · 10.1101/2024.09.10.612351

Measuring the neurodevelopmental trajectory of excitatory-inhibitory balance via visual gamma oscillations

Rhodes, N.·Rier, L.·Singh, K. D.·Sato, J.·Vandewouw, M. M.·Holmes, N.·Boto, E.·Hill, R. M.·Rea, M.·Taylor, M.·Brookes, M. J.
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Abstract

Disruption of the balance between excitatory and inhibitory neurotransmission (E-I balance) underlies theories of many neurodevelopmental disorders, however, its study is typically restricted to adults, animal models and the lab-bench. Neurophysiological oscillations in the gamma frequency band relate closely to E-I balance, and a new technology - OPM-MEG - offers the possibility to measure such signals across the lifespan. We used OPM-MEG to measure gamma oscillations induced by visual stimulation in >100 participants, aged 2-34 years. We demonstrate a significantly changing spectrum with age, with low amplitude broadband gamma oscillations in children and high amplitude band limited oscillations dominating in adults. We used a canonical cortical microcircuit to model these gamma signals, revealing significant age-related shifts in E-I balance in superficial pyramidal neurons in visual cortex. Our findings detail the first MEG metrics of gamma oscillations and their underlying generators from toddlerhood, providing a benchmark against which future studies can contextualise.

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Rhodes, N., Rier, L., Singh, K. D., Sato, J., Vandewouw, M. M., Holmes, N., Boto, E., Hill, R. M., Rea, M., Taylor, M., Brookes, M. J.. 2024-09-11. Measuring the neurodevelopmental trajectory of excitatory-inhibitory balance via visual gamma oscillations. https://doi.org/10.1101/2024.09.10.612351

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