Exploring the nonlinear dynamics of EEG signals

The application of the nonlinear mathematical methods to the electroencephalographic signals (EEG signals) began in 1985. One of the most promising approaches to define and determine, complexity, nonlinearity and nonstationnarity of EEG signals is recurrences method initiated by Eckmann, Kamphorst and Ruelle in 1987 under RP name then by Webber, Zbilut and Chau under RQA name. Implementation of recurrences method in biomedical field, was initiated by J. P. Zbilut then N. P. Chau in cardiovascular field. Their work concerned the variability of heartbeat rate in diabetic dysautonomy. For several years, our engineers team of research has been in collaboration with other doctors and clinicians. We use RQA method applied to EEG signals and we observe the RQA variables variations while hoping to detect a significant dynamics changes which can inform us on the arrival of epileptic seizure at convenient period