Non-Thermal Effect of Microwave Radiation on Human Brain

Abstract

This study focuses on an origin of interaction mechanism of microwave radiation with nervous system-quasi-thermal field effect. The microwave field can cause fluctuations and vibration of the charged particles and membranes in tissues. The hypothesis is, that this phenomenon is similar to the effect caused by Brown motion initiated by temperature and results in the same effects without rise in temperature. The electric field of 1 V/cm can introduce disturbance of the thermal equilibrium inside a cell of 10 µm radius, which is equivalent to disturbance produced by temperature rise of 1 K. The hypothesis, that microwave heating should cause an effect independent of the microwave modulation frequency, while field effect depends on modulation frequency, was examined experimentally. The 450 MHz microwave radiation, modulated at 7, 14 and 21 Hz frequencies, power density at the skin 0.16 mW/cm 2 , was applied. The experimental protocol consisted of two series of five cycles of the repetitive microwave exposure at fixed modulation frequencies. Relative changes in EEG theta, alpha and beta rhythms of the group of 13 healthy volunteers were analysed. Analysis of the experimental data shows that:(1) statistically significant changes in EEG rhythms depend on modulation frequency of the microwave field; (2) microwave stimulation causes an increase of the EEG energy level; (3) the effect is most intense at beta1 rhythm and higher modulation frequencies. These findings confirm the quasi-thermal origin of the effect, different from average heating.

Individual changes in human EEG caused by 450 MHz microwave modulated at 40 and 70 Hz

“…The analysis method was applied in our previous study (Hinrikus et al 2005), except for different comparison segments. The energies of the different EEG rhythms were analyzed separately.…”

“…Microwave exposure at the non-thermal level of field power density was selected identical to that in our previous studies except modulation frequencies (Lass et al 2002;Hinrikus et al 2004Hinrikus et al , 2005Bachmann et al 2004;Bachmann et al 2005a). Exposure conditions were the same for all subjects.…”

“…In our previous studies the relative changes in the EEG rhythms energy caused by microwave radiation modulated inside the EEG physiological spectrum at frequencies 7 Hz, 14 Hz and 21 Hz were investigated (Hinrikus et al , 2005. The conclusion was that the effect produced by microwave radiation has a clear frequency dependence and increases with modulation frequency.…”

“…The same exposure conditions utilized in our previous studies were applied (Hinrikus et al , 2005Bachmann et al 2004). The mechanism of low-level microwave effect on biological tissues is still not clear.…”

Demodulation effect is observed in neurones by exposure to low frequency modulated microwaves

“…400 MHz 100 % modulated in the EEG physiological spectrum, at frequencies of 7, 14 and 21 Hz showed increased alpha (8-13 Hz), and beta (13-30 Hz) rhythms. Alpha and beta rhythms were also activated by MW modulation at 40 Hz and 70 Hz [8]. This frequency band seems particularly susceptible to alteration subsequent to electromagnetic field exposure but this effect is not currently Fig.2.-a) SA, spontaneous activity.…”