HP11: Periodic and aperiodic properties of globus pallidus during head movements in patients with cervical dystonia: a case study

Abstract

The aim of the study was to analyze the pallidal activity during voluntary head movements in 3 cervical dystonia patients with torticollis and jerky movements, sinusoidal tremor, and retrocollis without tremor. Cervical dystonia (CD) is the most common form of focal dystonia, and it is typically characterized by abnormal postures of the head, which can be associated with jerky or sinusoidal head oscillations. Surgical treatment of refractory to medical management CD with deep brain stimulation (DBS) of globus pallidus has been successful. We analyzed local field potentials recorded from globus pallidus on the second day after DBS surgeries during voluntary head movements simultaneously with EMG of neck muscles. We used a method of parameterizing neuronal power spectra into periodic and aperiodic (1/f) components [1]. In a patient with torticollis, we showed that head movement to the direction opposite torticollis caused significantly higher aperiodic spectra component (1/f) in contrast to a straight position and head movement in an ipsilateral direction, which caused significantly higher beta and gamma oscillations. We didn’t find any differences in both aperiodic and periodic components for a retrocollis patient without tremor. Head movement in both directions was characterized by significantly lower theta and alpha oscillations in comparison with the straight position in a patient with sinusoidal tremor. Our preliminary data showed the differences in motor control of head movement in globus pallidus of CD patients with different manifestations. [1] Donoghue, T., et al. Parameterizing neural power spectra into periodic and aperiodic components. Nat Neurosci 23, 1655–1665 (2020).