Driving Cerebellar Theta Oscillations Interferes With Voluntary Neck Movements in Cervical Dystonia

Area of Science:

• Neuroscience
• Movement Disorders
• Neuromodulation

Background:

• Cervical dystonia (CD) is a complex movement disorder involving cerebellar abnormalities.
• Transcranial alternating current stimulation (tACS) is a noninvasive technique that modulates brain oscillations.
• Cerebellar tACS can influence neuronal activity and resonant rhythms.

Purpose of the Study:

• To investigate if cerebellar tACS at resonant frequencies affects voluntary neck movements in CD patients.
• To determine if botulinum toxin (BoNT) therapy influences the effects of cerebellar tACS.

Main Methods:

• Eighteen CD patients (torticollis phenotype) underwent motion analysis of neck movements.
• Cerebellar tACS was applied at theta, beta, and gamma frequencies, plus sham, pre- and post-BoNT therapy.
• Peak angular velocity and amplitude of neck movements were measured.

Main Results:

• Cerebellar theta (θ)-tACS decreased velocity and amplitude of antidystonic neck movements in the OFF-BoNT state.
• This effect was more pronounced with ipsilateral cerebellar stimulation.
• BoNT therapy improved movement but did not mitigate the detrimental impact of θ-tACS.

Conclusions:

• Cerebellar theta oscillations negatively impact fast voluntary neck movements in CD.
• Botulinum toxin therapy does not alter the effects of cerebellar theta stimulation.
• These findings underscore the cerebellum's significant role in the network pathophysiology of dystonia.