Medical/biological study (experimental study)

Integration of differences in EEG Analysis Reveals Changes in Human EEG Caused by Microwave med./bio.

By: Bachmann M, Lass J, Kalda J, Sakki M, Tomson R, Tuulik V, Hinrikus H

Published in: 2006 International Conference of the IEEE Engineering in Medicine and Biology Society, New York, NY, USA. IEEE, 2006: pp. 1597-1600; ISBN 978-1-4244-0032-4

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Aim of study (acc. to author)

This study was focused on detection of the effect of microwave irradiation modulated with pulses of different frequencies on human EEG rhythm.

Background/further details

Seventy healthy vonlunteers were sham exposed and electromagnetic field exposed in four groups with following pulse frequencies: 7, 14, 21, 40, 70, 217, and 1000 Hz.

Endpoint

effects on the neurological system: effects on EEG rhythm

Exposure

- low level microwaves

Exposure	Parameters
Exposure 1: 450 MHz Modulation type: pulsed Exposure duration: intermittent, 1 min on/1 min off, for 10 x at each pulse rate	power density: 0.16 mW/cm² SAR: 0.35 W/kg

General information

The experiments were performed on four groups of subjects with different pulse rates. After recording the reference EEG for 10 minutes, exposure at the first pulse rate was applied, followed by one or two further pulse rates according to the considered group. During each test session, RF and sham exposure as well as the succession of pulse rates were randomly assigned.

Exposure 1

Main characteristics

Frequency	450 MHz
Type	electromagnetic field
Exposure duration	intermittent, 1 min on/1 min off, for 10 x at each pulse rate

Modulation

Modulation type	pulsed
Duty cycle	50 %
Repetition frequency	7 Hz
Additional info	group 2: 7, 14, and 21 Hz group 3: 40 and 70 Hz group 4: 217 and 1000 Hz

Exposure setup

Exposure source	quarter wave antenna (13 cm)
Distance between exposed object and exposure source	10 cm
Setup	The antenna was located 10 cm from the left side of the head.
Sham exposure	A sham exposure was conducted.

Parameters

Measurand	Value	Type	Method	Mass	Remarks
power density	0.16 mW/cm²	-	estimated	-	-
SAR	0.35 W/kg	-	estimated	-	-

Measurement and calculation details

Field power density at the skin and SAR were estimated by the measured calibration curves.

Exposed system:

human
partial body: left side of the head

Methods Endpoint/measurement parameters/methodology

effects on the neurological system: effects on EEG rhythm (EEG analysis was performed using three different calculation methods: S-parameter, power spectral density, and length distribution of low variability periods)

Investigated system:

investigation on living organism

Investigated organ system:

brain/CNS

Time of investigation:

before exposure
during exposure
after exposure

Main outcome of study (acc. to author)

Statistically significant changes occured in the EEG rhythm energy and dynamics between 12% and 30% of subjects. Theta wave was least affected. Most changes were observed in beta waves. Concerning brain region major changes were revealed in temporal-parietal brain region. Statistically significant changes in the EEG rhythms took place at the pulse frequencies higher or close to the EEG rhythm frequency.

Study character:

medical/biological study
experimental study
full/main study
blind study

Study funded by

Estonian Science Foundation (ETF), Estonia

Suhhova A et al. (2009): Effect of modulated microwave radiation on human EEG asymmetry
Hinrikus H et al. (2009): Effect of modulated at different low frequencies microwave radiation on human EEG
Hinrikus H et al. (2008): Effect of low frequency modulated microwave exposure on human EEG: Individual sensitivity
Suhhova A et al. (2008): Effect of Microwave Radiation on EEG Coherence
Bachmann M et al. (2007): Modulated microwave effects on individuals with depressive disorder
Bachmann M et al. (2007): Individual changes in human EEG caused by 450 MHz microwave modulated at 40 and 70 Hz
Bachmann M et al. (2005): Non-linear analysis of the electroencephalogram for detecting effects of low-level electromagnetic fields
Hinrikus H et al. (2005): Non-Thermal Effect of Microwave Radiation on Human Brain
Hinrikus H et al. (2004): Changes in human EEG caused by low level modulated microwave stimulation
Lass J et al. (2002): Effects of 7 Hz-modulated 450 MHz electromagnetic radiation on human performance in visual memory tasks
Krause CM et al. (2000): Effects of electromagnetic field emitted by cellular phones on the EEG during a memory task
Koivisto M et al. (2000): Effects of 902 MHz electromagnetic field emitted by cellular telephones on response times in humans
Koivisto M et al. (2000): The effects of electromagnetic field emitted by GSM phones on working memory
Krause CM et al. (2000): Effects of electromagnetic fields emitted by cellular phones on the electroencephalogram during a visual working memory task