Non-invasive suppression of essential tremor via phase-locked disruption of its temporal coherence
Sebastian R. Schreglmann, David Wang, Robert L. Peach, Junheng Li, Xu Zhang, Anna Latorre, E. J. Rhodes, Emanuele Panella, Antonino M. Cassarà, Edward S. Boyden, Mauricio Barahona, Sabato Santaniello, John C. Rothwell, Kailash P. Bhatia, Nir Grossman
Abstract
Aberrant neural oscillations hallmark numerous brain disorders. Here, we first report a method to track the phase of neural oscillations in real-time via endpoint-corrected Hilbert transform (ecHT) that mitigates the characteristic Gibbs distortion. We then used ecHT to show that the aberrant neural oscillation that hallmarks essential tremor (ET) syndrome, the most common adult movement disorder, can be transiently suppressed via transcranial electrical stimulation of the cerebellum phase-locked to the tremor. The tremor suppression is sustained shortly after the end of the stimulation and can be phenomenologically predicted. Finally, we use feature-based statistical-learning and neurophysiological-modelling to show that the suppression of ET is mechanistically attributed to a disruption of the temporal coherence of the aberrant oscillations in the olivocerebellar loop, thus establishing its causal role. The suppression of aberrant neural oscillation via phase-locked driven disruption of temporal coherence may in the future represent a powerful neuromodulatory strategy to treat brain disorders.