Classification of time-frequency EEG responses of patients with disorders of consciousness

• Autorzy: Chabuda A. , Rozanski P. , Dovgialo M. , Duszyk A. , Pietrzak M. , Zieleniewska M. , Durka P.J.
• Języki publikacji: EN

Abstrakty

EN

INTRODUCTION: Event-related (de-)synchronization (ER(D)S) is a short‑lasting modulation of specific frequency bands (e.g. alpha band) of EEG, which occurs in response for external stimuli (visual, haptic) or with motor imagery and execution of movements. Since it’s both time- and frequency‑specific, it is typically analysed in time‑frequency space, using Fourier or wavelet methods. AIM(S): As part of the research project of University of Warsaw’s Faculty of Physics and Warsaw’s “Alarm Clock Clinic” (Klinika Budzik), we try to assess whether the presence of a ER(D)S in EEG can be used as an indicator of consciousness in DOC (disorders of consciousness) patients. METHOD(S): Results from two paradigms are presented: 1) motor imagery experiments consisting of a series of auditory commands (“move your hand/leg”) and, 2) haptic stimulation sessions of vibrations applied to patient’s shoulder/hand, while the patient was instructed to focus on stimuli delivered to given location. EEG (23 electrodes from extended 10-20 system) and EMG signals were recorded. EEG data were analysed in time-frequency space to identify whether any statistically significant ER(D)S had occurred. RESULTS: Assessments of possible conscious responses reflected in EEG were correlated with the patients’ CRS‑R (Coma Recovery Scale-Revised) diagnosis and, in case of ER(D)S, with corresponding EMG signal. We present results of several possible indicators, based both on the statistical significance of time‑frequency features, as well as on the cross‑validated classification accuracy. CONCLUSIONS: While the major problem we encountered was caused by severe contamination of EEG with involuntary movement artifacts, we noted that EEG patterns of DOC patients are far from uniform, which is related not only to the patients’ neurological state, but also to physical skull defects and reconstructions. Instead of the classical approach of comparing the patterns of patients to the control group, we propose to look for any statistically stable traces of conscious responses. FINANCIAL SUPPORT: This research was supported by the Polish National Science Centre grant 2015/17/B/ ST7/03784.

• Wydawca: -
• Czasopismo: Acta Neurobiologiae Experimentalis
• Rocznik: 2017
• Tom: 77
• Numer: Suppl.1
• Opis fizyczny: p.61

Twórcy

autor

Chabuda A.

• Faculty of Physics, University of Warsaw, Warsaw, Poland

autor

Rozanski P.

• College of Inter-Faculty Individual Studies in Mathematics and Natural Sciences (MISMaP), University of Warsaw, Warsaw, Poland

autor

Dovgialo M.

• Faculty of Physics, University of Warsaw, Warsaw, Poland

autor

Duszyk A.

• Faculty of Physics, University of Warsaw, Warsaw, Poland

autor

Pietrzak M.

• Faculty of Physics, University of Warsaw, Warsaw, Poland

autor

Zieleniewska M.

• Faculty of Physics, University of Warsaw, Warsaw, Poland

autor

Durka P.J.

• Faculty of Physics, University of Warsaw, Warsaw, Poland