Effects of weak microwave fields amplitude modulated at ELF on EEG of symmetric brain areas in rats

Abstract

Averaged electroencephalogram (EEG) frequency spectra were studied in eight unanesthetized and unmyorelaxed adult male rats with chronically implanted carbon electrodes in symmetrical somesthetic areas when a weak (0.1–0.2 mW/cm) microwave (MW, 945 MHz) field, amplitude‐modulated at extremely low frequency (ELF) (4 Hz), was applied. Intermittent (1 min “On,” 1 min “Off”) field exposure (10‐min duration) was used. Hemispheric asymmetry in frequency spectra (averaged data for 10 or 1 min) of an ongoing EEG was characterized by a power decrease in the 1.5–3 Hz range on the left hemisphere and by a power decrease in the 10–14 and 20–30 Hz ranges on the right hemisphere. No differences between control and exposure experiments were shown under these routines of data averaging. Significant elevations of EEG asymmetry in 10–14 Hz range were observed during the first 20 s after four from five onsets of the MW field, when averaged spectra were obtained for every 10 s. Under neither control nor pre‐ and postexposure conditions was this effect observed. These results are discussed with respect to interaction of MW fields with the EEG generators. Bioelectromagnetics 18:293–298, 1997. © 1997 Wiley‐Liss, Inc.

Non-Thermal Effect of Microwave Radiation on Human Brain

“…Despite extensive research in the field of low-level microwave effects on the nervous system during recent decades (Johnson and Guy, 1972;Bawin et al, 1973;Baranski and Edelwejn, 1975;Gavalas-Medici and Day-Magdaleno, 1976;Chizhenkova, 1988;Mann and Roschke, 1996;Vorobyov et al, 1997;Wagner et al, 1998;Lutty et al, 2000), the reports of possible effects are often contradictory and the mechanisms behind the effects are still unclear. The difficulties in independent repeating of the experimental results cause doubt in these effects.…”

“…Several investigators have reported that microwave exposure produces different alterations in the EEG signal: an increase in the number of slow rhythms in the EEG of rabbits (Chizhenkova, 1988), modulated at brain rhythm frequencies EMF affect EEG patterns in the cat (Bawin et al, 1973), a significant elevation of the EEG hemispheric asymmetry during the first 20 seconds of the stimulation period (Vorobyov et al, 1997).…”

Effect of 450 MHz Microwave Modulated with 217 Hz on Human EEG in Rest

“…The reports of possible non-thermal effects are often contradictory. Several investigators have reported that low-level exposure produces alterations in the EEG signal and brain behavior (Bawin et al, 1973;Vorobyov et al, 1997;Mann et al, 1996;Wagner et al, 1998;Huber et al, 2000;Lass et al, 2002;Hinrikus et al, 2004). The conclusion reported by the other researchers is that the exposure to electromagnetic field does not alter the resting EEG (Hietanen et al, 2000;.…”

Neural Network-Based Evaluation of Chronic Non-Thermal Effects of Modulated 2450 MHz Microwave Radiation on Electroencephalogram

“…However, a close association between microwave and brain function has been identified and reviewed by D'Andrea et al 12 Available literature demonstrates the effects of different frequencies of microwave exposure of varied power densities on brain electrophysiology. 2,18,19,28,53 Agrawal 1 worked exclusively on chronic exposure of 1 kHz-modulated microwave frequency of 2450 MHz and examined the relationship between behavior and thyroid hormones of female rats. This study had suggested that chronic exposure of lowenergy-modulated microwave (2450 MHz) significantly affects hypothalamo-pituitary-thyroid axis, which finally results in alterations in behavior and concentration of thyroid hormone of the subjects.…”