136 Practical Biomedical Signal Analysis Using MATLAB
R
New approaches in anticipating seizures involve the so-called active algorithms in
contrast to passive algorithms described above. The active probe may be intermittent
photic stimulation. It was found [Kalitzin et al., 2002, Parra et al., 2003] that in EEG
and MEG signals, before the seizure onset, the phenomenon of phase clustering of
harmonically related frequency components occurs. It doesn’t mean that the stimulus
provokes the seizure in any way. Based on this observation phase clustering index
(PCI), which reflects the ability of neuronal systems to generate epileptic discharges,
was introduced [Kalitzin et al., 2002]. PCI is zero if the phases are random, and tends
toward high values if the ...