Study type: Medical/biological study (experimental study)

Effect of Microwave Radiation on EEG Coherence. med./bio.

Published in: 14th Nordic-Baltic Conference on Biomedical Engineering and Medical Physics. IFMBE, 2008: 331-334, ISBN 9783540693666

Aim of study (acc. to author)

To investigate the effect of modulated microwave exposure on the EEG coherence in healthy and depressive persons.

Background/further details

Characteristic changes in the EEG pattern in patients with depressive disorder are related to spatial phenomena in the brain. These can be measured by the signal coherence (similar waveform) of two electrode positions, i.e. brain regions, of a certain frequency band in the EEG. High coherence between EEG signals of two brain regions is interpreted as increased functional cooperation between these regions.
18 healthy women and 18 women with major depressive disorder were exposed and sham-exposed in randomized order. EEG coherence between frontal, temporal, parietal and occipital electrode channels was considered.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 450 MHz
Exposure duration: continuous for 30 min

Exposure 1

Main characteristics
Frequency 450 MHz
Type
Exposure duration continuous for 30 min
Modulation
Modulation type cf. additional info
Additional info

pulse modulation with a modulation frequency of 1000 Hz and a duty factor of 50 %

Exposure setup
Exposure source
Distance between exposed object and exposure source 10 cm
Setup antenna located near the skin of the head's left side
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
power density 1.6 mW/cm² - estimated - at the skalp
power 10 W - - - -
SAR 0.3 W/kg maximum calculated - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Investigated organ system:
Time of investigation:
  • during exposure

Main outcome of study (acc. to author)

Significant changes in EEG coherence caused by microwave exposure could not be detected on the group level, but only in individual persons: Increased EEG coherence was observed for healthy women in theta waves (3 subjects) and alpha waves (2 subjects) over the frontal and temporal region, as well as decrease in alpha waves over the parietal and occipital region. In women with major depression significant changes in EEG coherence were observed in beta wave 2 (2 subjects) over frontal and temporal region and in alpha wave (3 subjects) over temporal and parietal region. The rate of individual subjects affected by microwave exposure was the same in both groups.

Study character:

Study funded by

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