Amiri Fallah Z, Firoozabadi M, Shafiei A, Assadi A. Scrutiny of brain signals variations in regions Cz, C3 and C4 under Local Exposure of Extremely Low Frequency and Weak pulsed Magnetic Field to promote Neurofeedback systems. Physiol Pharmacol 2011; 15 (1) :144-163
URL:
http://ppj.phypha.ir/article-1-686-en.html
Abstract: (12245 Views)
Introduction: Researchers have long been interested in the effects of low intensity (less than 500 microtesla) and
Extremely Low Frequency Magnetic Fields (ELF-MF, less than 300 Hz) on human’s brain activity. In this study, our
purpose was to analyze the effect of local magnetic field pulses around brain regions Cz, C3, C4 on human
electroencephalogram (EEG) and induction of resonance effect formedical utilization in Low Energy Neurofeedback
System (LENS).
Methods: EEG of 15 healthy women was recorded in four sessions (3 exposure sessions and one session as sham).
In exposure sessions, ELF-MF pulses were exerted locally for 3 minutes with intensities of 100, 200 and 300 microtesla
with frequencies of 10 Hz on region Cz, 18 Hz on region C3 and 14 Hz on region C4. Frequency bands power were
extracted from participants' EEGs and were compared during, before and after the exposure with each other andwith
the sham session. Comparison between exposure groups and sham group were performed with independent t-test and
paired t-test.
Results: The results showed that pulsed and local ELF-MF decreases the beta band power in all three regions during
the exposure (7.9 to 11.6 percent) in comparison with before the exposure with 95% certainty. Meanwhile developed
variations during the exposure are transient and different from variations after interruption of exposure. The resonance
effect was observed nowhere around the regions.
Conclusion: Exertion of ELF-MF pulses on human brain locally change the EEG pattern and alterations persist for
15 minutes after exposure. Also EEG of other central regions varies. Therefore for recognition of effects of these fields
and application of them in LENS we should consider simultaneous exposure and interhemispheric ELF-MF.