Basic Studies on Mechanism of Biological Effects of Extremely Low Frequency Electric Fields

使用已获得厚生省授权并已证实安全性的电场暴露设备，EEG，ECG，血压，外周皮肤温度暴露ELF同时测量并分析了人体极低频电场，测量了脑电，分析了σ、θ、α、β节律各谱功率的变化，然后评估唤醒水平的变化。得到的结果如下。由于电场暴露后BEG的低频成分增加，BEG分析的振幅指数中的唤醒水平下降。当电场暴露于受试者时，体毛振动。因此，受试者会将振动检测为场暴露，因此心理效应可能会影响受试者。为了验证这种效应的可能性，引入了以下实验。为了掩盖现场暴露引起的毛发振动感，并长时间保持唤醒水平，在相同的实验中，向受试者呈现波动的风和白色噪声声音。结果表明，电场暴露后，觉醒水平有升高的趋势，暴露后又恢复到原来的水平。电场暴露前手部皮肤温度呈上升趋势，但暴露过程中手部皮肤温度呈下降趋势，暴露后手部皮肤温度下降趋势进一步加剧。在心率变异性频谱分析的基础上，分析了交感和副交感神经系统的活动。在电场暴露期间和之后，副交感神经活动减弱，但交感神经活动被激活。

Using electric field exposure equipment that it receives the authorization of Ministry of Health and Welfare and has already confirmed of the safety, EEG, ECG, blood pressure, peripheral skin temperature in exposing ELF( Extremely Low Frequency) electric field on human body were measured simultaneously and analyzed.The EEG was measured and the variation of each spectral power of σ, θ, α, β rhythm was analyzed, and thereafter the variation of arousal level was evaluated. The result was obtained as follows. The arousal level dropped in amplitude index of the BEG analysis because of the low-frequency-component of the BEG increasing after the electric field exposure.When a electric field was exposed to a subject, the body hair was vibrating. Hence the subject would detected the vibration as a field exposure, and therefore psychological effect might affect the subject. To verify the possibility of this effect, the following experiment was introduced. To covering the sense of vibrating hair by field exposure and maintaining the arousal level long time, fluctuating wind and white noise sound were presented to the subject in the same experiments. As a result, the arousal level tended to rise under electric field exposure, and it returns in original level after the exposure.Next, hand skin temperature, BEG, ECG and blood pressure were analyzed. Although hand skin temperature was upward trend before electric field exposure, it was changed to the declining tendency during the field exposure, and it intensified the declining tendency still more after the field exposure. The activity of sympathetic and parasympathetic nerve systems were analyzed based on the spectrum analyses of heart rate variability. During and after the electric field exposure, the parasympathetic nerve activity was weakened but the sympathetic nerve activity was activated.