Bispectrum for the detection of the effect of photic and microwave stimulation on human EEG

The effects of microwave radiation on the electrical activity of human brain have been studied on a small group of young healthy volunteers. For estimation of the location of possible effects, the following EEG channels were utilized: F3, F4, T3, T4, O1, O2. The experiments included repeated microwave radiation at 450 MHz with modulating frequency 7 Hz and 16 Hz photic stimulation. For comparing the brain activity in different situations, three parameters from the EEG bispectrum were calculated. The results indicate that those parameters could not detect the influence of very low microwave radiation. However, the first parameter named normalized alpha could detect the onset and the end of photic stimulation in occipital region and the onset of photic stimulation in the frontal and temporal region. As far as microwave radiation is concerned, those parameters should be analyzed again while more intense fields are studied.