Experiment 1: Modulation of Physiological Tremor in Healthy Volunteers Thirty healthy volunteers will undergo TUS targeting the dentate nucleus in a randomized, double-blinded crossover design. Tremor amplitude, induced by a 15 g weight, will be measured using an accelerometer, and EEG will assess neural oscillations and cerebello-thalamo-cortical connectivity.
Stimulation will include short-term (1 minute on/off for 12 minutes) and long-term (30 minutes) protocols, as well as closed-loop TUS for phase-specific effects. This experiment aims to optimize stimulation parameters and explore the dentate nucleus's role in tremor generation.
Experiment 2: Tremor Modulation in Essential Tremor Patients Thirty ET patients will receive TUS targeting the dentate nucleus with optimized parameters from Experiment 1 in a randomized crossover design. The best protocol from previous experiment will be tested here. Tremor amplitude and EEG will be recorded to assess short- and long-term effects of TUS on pathological tremor.