4 research outputs found
Evaluating the Changes in Alpha-1 Band Due to Exposure to Magnetic Field
Introduction Increase in alpha band is observed when blood perfusion in frontal area of head decreases. The present study evaluated some changes in the alpha band particularly, alpha-1 of frontal and central areas of the head, when several areas were exposed simultaneously to magnetic field. Materials and Methods Five points of head (F3, F4, Cz, T3, and T4) of twenty healthy male participants were exposed to magnetic fields simultaneously by five separate coils at different frequencies of 45, 17, 10, 5, and 3 Hz, in five separate sessions. The magnetic field intensity was 100 µT at 1.5 cm distance from the coil. At the end, relative powers over these areas in common frequency and alpha-1 bands were evaluated by paired t-test. Results Significant reduction (
EEG changes during exposure to extremely low frequency magnetic field on a small area of brain
Introduction: Effects of extremely low frequency magnetic fields (ELF-MF) with different intensities and frequencies has been investigated by several researchers. In most of these studies, the applied magnetic field has uniformly encountered whole brain and it has shown that changing intensity and frequency causes anomaly changes in electroencephalograms. The aim of current study was to investigate the effect of local exposure to ELF-MF with different intensities on EEG signals. Material and methods: Magnetic field with frequency of 10 Hz and intensity of 100, 120, 160, 200, 240, 280, 320 and 360 µT was applied to F3 zone in 10-20 system of 3 men locally. Finally, relative power spectrum in 5 points of head in conventional frequency bands was assessed. Results: An increase in alpha band in regions under exposure such as F3 and O1 in intensities of 100 and 360 µT was observed. No changes in other bands such as theta band were found. It should be noted that none of the above effects was observed in closed-eye position. Conclusion: Regular effects due to increasing intensity of magnetic field was not observed and changing potential of EEG signals from magnetic field with intensity of 100 and 360 µT is more than other intensities. Changing pattern of alpha band in F4, Cz, O2 and O1 was similar to exposed F3 zone and no resonance effect was observed at 10 Hz magnetic field