Sleep EEG alterations: effects of pulsed magnetic fields versus pulse‐modulated radio frequency electromagnetic fields

Studies have repeatedly shown that electroencephalographic power during sleep is enhanced in the spindle frequency range following radio frequency electromagnetic field exposures pulse‐modulated with fundamental frequency components of 2, 8, 14 or 217 Hz and combinations of these. However, signals used in previous studies also had significant harmonic components above 20 Hz. The current study aimed: (i) to determine if modulation components above 20 Hz, in combination with radio frequency, are necessary to alter the electroencephalogram; and (ii) to test the demodulation hypothesis, if the same effects occur after magnetic field exposure with the same pulse sequence used in the pulse‐modulated radio frequency exposure. In a randomized double‐blind crossover design, 25 young healthy men were exposed at weekly intervals to three different conditions for 30 min before sleep. Cognitive tasks were also performed during exposure. The conditions were a 2‐Hz pulse‐modulated radio frequency field, a 2‐Hz pulsed magnetic field, and sham. Radio frequency exposure increased electroencephalogram power in the spindle frequency range. Furthermore, delta and theta activity (non‐rapid eye movement sleep), and alpha and delta activity (rapid eye movement sleep) were affected following both exposure conditions. No effect on sleep architecture and no clear impact of exposure on cognition was observed. These results demonstrate that both pulse‐modulated radio frequency and pulsed magnetic fields affect brain physiology, and the presence of significant frequency components above 20 Hz are not fundamental for these effects to occur. Because responses were not identical for all exposures, the study does not support the hypothesis that effects of radio frequency exposure are based on demodulation of the signal only.

[1]  R. Croft,et al.  Dosimetric evaluation and comparison of different RF exposure apparatuses used in human volunteer studies , 2008, Bioelectromagnetics.

[2]  A. Ahlbom.  Guidelines for limiting exposure to time-varying electric, magnetic, and electromagnetic fields (up to 300 GHz) , 1998 .

[3]  Joachim Röschke,et al.  Effects of Pulsed High-Frequency Electromagnetic Fields on the Neuroendocrine System , 1998, Neuroendocrinology.

[4]  Niels Kuster,et al.  Sleep after mobile phone exposure in subjects with mobile phone‐related symptoms , 2011, Bioelectromagnetics.

[5]  Mark E Howard,et al.  Individual differences in the effects of mobile phone exposure on human sleep: rethinking the problem. , 2012, Bioelectromagnetics.

[6]  I Feinberg,et al.  Systematic trends across the night in human sleep cycles. , 1979, Psychophysiology.

[7]  Joachim Röschke,et al.  Human Sleep EEG under the Influence of Pulsed Radio Frequency Electromagnetic Fields , 2000, Neuropsychobiology.

[8]  P. Achermann,et al.  Radio frequency electromagnetic field exposure in humans: Estimation of SAR distribution in the brain, effects on sleep and heart rate , 2003, Bioelectromagnetics.

[9]  Peter Achermann,et al.  Pulsed radio‐frequency electromagnetic fields: dose‐dependent effects on sleep, the sleep EEG and cognitive performance , 2007, Journal of sleep research.

[10]  Volkert Hansen,et al.  Effects of short‐ and long‐term pulsed radiofrequency electromagnetic fields on night sleep and cognitive functions in healthy subjects , 2007, Bioelectromagnetics.

[11]  G. Ziegelberger,et al.  International commission on non-ionizing radiation protection. , 2006, Progress in biophysics and molecular biology.

[12]  P. Achermann,et al.  Exposure to pulsed high‐frequency electromagnetic field during waking affects human sleep EEG , 2000, Neuroreport.

[13]  A. Rechtschaffen.  A manual of standardized terminology, techniques and scoring system for sleep of human subjects , 1968 .

[14]  E. Wolpert.  A Manual of Standardized Terminology, Techniques and Scoring System for Sleep Stages of Human Subjects. , 1969 .

[15]  N. Kuster,et al.  Electromagnetic fields, such as those from mobile phones, alter regional cerebral blood flow and sleep and waking EEG , 2002, Journal of sleep research.

[16]  Peter Achermann,et al.  Pulsed high-frequency electromagnetic field affects human sleep and sleep electroencephalogram , 1999, Neuroscience Letters.

[17]  Giuseppe Curcio,et al.  Systematic review and meta-analysis of psychomotor effects of mobile phone electromagnetic fields , 2010, Occupational and Environmental Medicine.

[18]  J Röschke,et al.  Human sleep under the influence of pulsed radiofrequency electromagnetic fields: a polysomnographic study using standardized conditions. , 1998, Bioelectromagnetics.

[19]  Peter Achermann,et al.  Pulsed radio frequency radiation affects cognitive performance and the waking electroencephalogram , 2007, Neuroreport.

[20]  J Röschke,et al.  Effects of pulsed high-frequency electromagnetic fields on human sleep. , 1996, Neuropsychobiology.

[21]  Con Stough,et al.  The effect of electromagnetic fields emitted by mobile phones on human sleep , 2005, Neuroreport.

[22]  N. Kuster,et al.  Exposure to pulse‐modulated radio frequency electromagnetic fields affects regional cerebral blood flow , 2005, The European journal of neuroscience.

[23]  Peter Achermann,et al.  Cognitive Performance Measures in Bioelectromagnetic Research - Critical Evaluation and Recommendations , 2011, Environmental health : a global access science source.

[24]  W. R. Adey,et al.  Sensitivity of calcium binding in cerebral tissue to weak environmental electric fields oscillating at low frequency. , 1976, Proceedings of the National Academy of Sciences of the United States of America.

[25]  Peter Achermann,et al.  Sleep EEG alterations: effects of different pulse‐modulated radio frequency electromagnetic fields , 2012, Journal of sleep research.

[26]  Quirino Balzano,et al.  Absence of nonlinear responses in cells and tissues exposed to RF energy at mobile phone frequencies using a doubly resonant cavity , 2010, Bioelectromagnetics.