Effects of high-frequency electromagnetic fields on human EEG: a brain mapping study.
Cell phones emitting pulsed high-frequency electromagnetic fields (EMF) may affect the human brain, but there are inconsistent results concerning their effects on electroencephalogram (EEG). We used a 16-channel telemetric electroencephalograph (ExpertTM), to record EEG changes during exposure of human skull to EMF emitted by a mobile phone. Spatial distribution of EMF was especially concentrated around the ipsilateral eye adjacent to the basal surface of the brain. Traditional EEG was full of noises during operation of a cellular phone. Using a telemetric electroencephalograph (ExpertTM) in awake subjects, all the noise was eliminated, and EEG showed interesting changes: after a period of 10-15 s there was no visible change, the spectrum median frequency increased in areas close to antenna; after 20-40 s, a slow-wave activity (2.5-6.0 Hz) appeared in the contralateral frontal and temporal areas. These slow waves lasting for about one second repeated every 15-20 s at the same recording electrodes. After turning off the mobile phone, slow-wave activity progressively disappeared; local changes such as increased median frequency decreased and disappeared after 15-20 min. We observed similar changes in children, but the slow-waves with higher amplitude appeared earlier in children (10-20 s) than adults, and their frequency was lower (1.0-2.5 Hz) with longer duration and shorter intervals. The results suggested that cellular phones may reversibly influence the human brain, inducing abnormal slow waves in EEG of awake persons.
Kramarenko
Alexander V
AV
Central Clinic Hospital N5, Kharkov, Ukraine.
Tan
Uner
U
D000328:Adult; D001921:Brain / Q000502:physiology / Q000528:radiation effects*; D001931:Brain Mapping; D040421:Cell Phone; D002648:Child; D004569:Electroencephalography / Q000528:radiation effects*; D004574:Electromagnetic Fields; D006801:Humans; D008297:Male; D011846:Radio Waves; D012016:Reference Values; D013997:Time Factors