Аннотация:Background: Clinical asymmetry of motor symptoms is common for Parkinson disease (PD) patients. Modern research highlights that studying this patient group effectively reveals pathology-related patterns of neural activity. Coherent alpha (9-13 Hz) and low-beta (14-20 Hz) oscillations observed in local field potentials (LFP) in the basal ganglia were shown to correlate with disease progression, but coherence of single cell rhythmic activity is much less studied in this context.Methods: In this pilot study we utilized 98 microelectrode recordings (MER) of the STN neurons from 3 patients in the resting state who exhibited clinical asymmetry (UPDRS score difference between hemibodies ≥ 25%) during bilateral DBS implantation surgeries. Single-unit activity (SUA) and background spiking activity (BUA) were extracted from the recordings. Then, envelopes for these signals were created by applying a low-pass filter and underwent coherence analysis in the 5-40 Hz range.Results: We found that sites with significant SUA-BUA coherence were more numerous in the STN contralateral to the more affected hemibody (MA STN): 40% of all the analyzed recordings vs 23% in the ipsilateral STNs (LA STNs). This was observed in each separate patient. Moreover, in 2/3 patients alpha coherence was exclusively observed in the MA STN, reaching 23% and 14% of all the analyzed sites. High-beta (20-35 Hz) coherence was equally distributed between the MA/LA STNs and along the microelectrode trajectory. On the contrary, alpha/low-beta coherence sites appeared to localize primarily in the upper half of the STN, strengthening their relation to motor symptoms.Conclusions: Present study emphasizes the direct connection between hemibody motor symptoms severity in PD patients and the overall proportion of coherently oscillating neurons in the contralateral STNs. Moreover, our data suggests alfa coherence to be validly disease-related, sparking further investigation.The study was funded by the Russian Science Foundation (22-15-00344).
