Bispectrum analysis of focal ischemic cerebral EEG signal

A model for SD rat focal ischemic cerebral injury is presented. Based on this experimental model, the authors recorded the EEGs of an ischemic region and a normal region for 30 minutes. Then the authors used a third-order spectrum (TOR) method for estimating the bispectrum of these EEG signals, and found that some characteristics of these bispectra which were very sensitive to focal ischemic cerebral injury. The maximum bispectrum magnitude of EEG and the weighted center of bispectrum (WCOB) change sensitively to different injury regions and injury stages. The bispectrum analysis results were verified by the Heat Shock Protein (HSP) test. It is concluded that the ischemic and normal regions can be clearly distinguished by analyzing their EEG bispectra, and the extent can also be detected by this way