Study Explores Neuromodulation for Treating Essential Tremor Symptoms

A clinical study is exploring whether low-intensity focused ultrasound affects brain activity and tremor symptoms in participants diagnosed with essential tremor.  

The study is sponsored by San Francisco-based neurotechnology company Nudge to test Nudge Zero, an investigative neuromodulation device. Ultrasound-based neuromodulation is an emerging area of research in neurology, and early studies are exploring whether targeted sound waves can safely and noninvasively modulate brain circuits that cause tremor symptoms. The Nudge Zero device is guided by magnetic resonance imaging (MRI) to help visualize the targeted areas in real-time. 

The Nudge study does not yet aim to demonstrate safety or efficacy but rather gather preliminary data that may guide future clinical development. The company is developing similar studies for chronic pain, tinnitus, and substance use disorder. Principal investigator David Segar, M.D., a University of California—San Francisco-trained functional neurosurgeon, is overseeing the study. 

The trial is enrolling up to 150 adult participants with essential tremor at a San Francisco study site. Over an approximately three-week period, participants will complete multiple focused ultrasound sessions within an MRI machine, each lasting approximately two to three hours. Questionnaires and in-person evaluation will be used to assess tremor symptoms. Researchers are targeting the VIM thalamus and may also target the dentatorubrothalamic tract, brain regions known to be involved in essential tremor.

“Focused ultrasound neuromodulation is an emerging field, offering the ability to precisely target deep brain circuits implicated in conditions such as essential tremor, addiction, pain, anxiety, and rheumatoid arthritis,” Foundation Chairman Neal F. Kassell, M.D., said. “Its potential to modulate neural activity noninvasively could redefine how we treat brain disorders. Though the field is still in its early stages, we are encouraged to see clinical studies underway to fully understand its safety, efficacy, and optimal applications.”

Another clinical trial is ongoing using low-intensity focused ultrasound neuromodulation to target the brain’s dentatorubrothalamic tract to help alleviate the symptoms of essential tremor.