EEG Detection and Prediction of Freezing of Gait in Parkinson's Disease Based on Spatiotemporal Coherent Modes.

Objective: Freezing of gait (FOG) in Parkinson's disease has a complex neurological mechanism. Compared with other modalities, electroencephalogram (EEG) can reflect FOG-related brain activity of both motor and non-motor symptoms. However, EEG-based FOG prediction methods often extract time, spatial, frequency, time-frequency, or phase information separately, which fragments the coupling among these heterogeneous features and cannot completely characterize the brain dynamics when FOG occurs.

Methods: In this study, dynamic spatiotemporal coherent modes of EEG were studied and used for FOG detection and prediction. A dynamic mode decomposition (DMD) method was first applied to extract the spatiotemporal coherent modes. Dynamic changes of the spatiotemporal modes, in both amplitude and phase of motor-related frequency bands, were evaluated with analytic common spatial patterns (ACSP) to extract the essential differences among normal, freezing, and transitional gaits.

Results: The proposed method was verified in practical clinical data. Results showed that, in the detection task, the DMD-ACSP achieved an accuracy of 86.4 ± 3.6% and a sensitivity of 83.5 ± 4.3%. In the prediction task, 86.5 ± 3.2% accuracy and 86.7 ± 7.8% sensitivity were achieved.

Conclusion: Comparative studies showed that the DMD-ACSP method significantly improves FOG detection and prediction performance. Moreover, the DMD-ACSP reveals the spatial patterns of dynamic brain functional connectivity, which best discriminate the different gaits.

Significance: The spatiotemporal coherent modes may provide a useful indication for personalized intervention and transcranial magnetic stimulation neuromodulation in medical practices.