Dergi makalesi Açık Erişim

Identification of nonlinear features in cortical and subcortical signals of Parkinson's Disease patients via a novel efficient measure

2020    Ozkurt, Tolga Esat; Akram, Harith; Zrinzo, Ludvic; Limousin, Patricia; Foltynie, Tom; Oswal, Ashwini; Litvak, Vladimir

This study offers a novel and efficient measure based on a higher order version of autocorrelative signal memory that can identify nonlinearities in a single time series. The suggested method was applied to simultaneously recorded subthalamic nucleus (STN) local field potentials (LFP) and magnetoencephalography (MEG) from fourteen Parkinson's Disease (PD) patients who underwent surgery for deep brain stimulation. Recordings were obtained during rest for both OFF and ON dopaminergic medication states. We analyzed the bilateral LFP channels that had the maximum beta power in the OFF state and the cortical sources that had the maximum coherence with the selected LFP channels in the alpha band. Our findings revealed the inherent nonlinearity in the PD data as subcortical high beta