To compare the sensibility of non-linear analysis of length distribution of low-variability periods (LDLVP) and linear spectral analysis to study EEG signals with and without the influence of a low-level modulated microwave field.
|Modulation frequency||7 Hz|
|Modulation depth||100 %|
The LDLVP method provided a significant detection of the effect of the microwave stressor for six subjects exposed to the microwave field but for none of the sham exposure recordings. The spectral power analysis revealed a significant result for one subject only. A significant effect of the exposure on the EEG signal was detected in 25% of subjects (by LDLVP analysis): microwave exposure increased EEG variability. The effect was not detectable by power spectral measures.
In conclusion, non-linear LDLVP method is a sensitive method for distinguishing EEG signals with and without a weak stressor and is superior to spectral analysis.