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bioRxiv · 10.1101/2021.09.21.461109

Transcranial Focused Ultrasound Neuromodulation of the Thalamic Visual Pathway in a Large Animal Model

Mohammadjavadi, M.·Ash, R. T.·Gaur, P.·Kubanek, J.·Saens, Y.·Glover, G. H.·Popelka, G. R.·Norcia, A. M.·Pauly, K. B.
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Abstract

BackgroundNeuromodulation of deep brain structures via transcranial ultrasound stimulation (TUS) is a promising, but still elusive approach to non-invasive treatment of brain disorders. ObjectiveThe purpose of this study was to determine whether MR-guided TUS of the lateral geniculate nucleus (LGN) can modulate visual evoked potentials (VEPs) and cortical brain oscillations in a large animal model. MethodsThe lateral geniculate nucleus (LGN) on one side was identified with T2-weighted MRI in sheep (all male, n=9). MR acoustic radiation force imaging (MR-ARFI) was used to confirm a tight sonication focus. Electroencephalographic (EEG) signals were recorded, and the visual evoked potential (VEP) peak-to-peak amplitude (N70 and P100) was calculated for each trial. Time-frequency spectral analysis was performed to elucidate the effect of TUS on cortical brain dynamics. ResultsThe VEP peak-to-peak amplitude was reversibly suppressed relative to baseline during TUS. Dynamic spectral analysis demonstrated a change in cortical oscillations when TUS is paired with visual sensory input, but not when TUS is applied by itself. ConclusionTUS non-invasively delivered to LGN can neuromodulate visual activity and oscillatory dynamics in large mammalian brains.

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Mohammadjavadi, M., Ash, R. T., Gaur, P., Kubanek, J., Saens, Y., Glover, G. H., Popelka, G. R., Norcia, A. M., Pauly, K. B.. 2021-09-24. Transcranial Focused Ultrasound Neuromodulation of the Thalamic Visual Pathway in a Large Animal Model. https://doi.org/10.1101/2021.09.21.461109

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