Changes in human EEG alpha activity following exposure to two different pulsed magnetic field sequences

Abstract

The present study investigates the effects of a weak (+/-200 microT(pk)), pulsed, extremely low frequency magnetic field (ELF MF) upon the human electroencephalogram (EEG). We have previously determined that exposure to pulsed ELF MFs can affect the EEG, notably the alpha frequency (8-13 Hz) over the occipital-parietal region of the scalp. In the present study, subjects (n = 32) were exposed to two different pulsed MF sequences (1 and 2, used previously) that differed in presentation rate, in order to examine the effects upon the alpha frequency of the human EEG. Results suggest that compared to sham exposure, alpha activity was lowered over the occipital-parietal regions of the brain during exposure to Sequence 1, while alpha activity over the same regions was higher after Sequence 2 exposure. These effects occurred after approximately 5 min of pulsed MF exposure. The results also suggest that a previous exposure to the pulsed MF sequence determined subjects' responses in the present experiment. This study supports our previous observation of EEG changes after 5 min pulsed ELF MF exposure. The results of this study are also consistent with existing EEG experiments of ELF MF and mobile phone effects upon the brain.

The Alpha Band of the Resting Electroencephalogram Under Pulsed and Continuous Radio Frequency Exposures

“…Some relevant studies to which our results can be compared are those of Cook et al [19]- [20] which employed exposures that bear some spectral resemblance to those employed here (pulsed ELF exposures but with homogeneous exposure properties), and they reported both increases and decreases of alpha activity during and shortly after exposure. In addition Stevens reported a decrease of alpha activity after exposure to weak magnetic fields [28].…”

“…Due to the difference in spectral content of the ELF fields (compared to RF) it is possible that these fields may interact differently, if at all, with the human EEG. EEG studies with exposures that share some resemblance to the GSM-ELF fields have shown changes in resting brain activity (albeit inconsistently), thereby justifying further investigation with mobile phone-like exposure conditions [19]- [21].…”

The efficiency of pulsed electromagnetic field in refractory migraine headaches: a randomized, single-blinded, placebo-controlled, parallel group

“…25,33,34 Many of the studies from 1985 to 2005, gathered in a review article, illustrated the effect of the use of large spread spectrum of PEMF doses on decreasing headache activity. 17 Although most of these research studies had no control or comparison group, or had very brief follow-up periods and uncompleted reports of dosimeter.…”

Study on Improvement of Blood Stagnation by Pulsed Magnetic Field

“…For example, it was effective in reducing muscle soreness in marathon runners [4]. The effects of PMF stimulus on the autonomic nervous system and frontal lobe activities were evaluated in several papers [5,6]. Shupak et al showed that exposure to PMF stimulus has a potential analgesic effect with increased pain thresholds [3].…”