Bispectrum analysis of focal ischemic cerebral EEG by constrained third order mean

With an experimental model for SD (Sparague-Sawley) rat focal cerebral ischemia presented, the EEG (electroencephalogram) signals from ischemic and normal regions are extracted. A non-Gaussian AR model is used for the EEG signals and the order of AR model is determined by bispectral cross correlation (BCC). Then based on above AR model, the constrained third-order mean (CTOM) method is proposed to estimate the bispectrum of EEG signals. Results show that the ischemic and normal regions can be clearly distinguished by the bispectrum of EEG signals. Both the extent and location of focal cerebral ischemic can be detected by the proposed method.