Study type: Medical/biological study (experimental study)

The spectral power coherence of the EEG under different EMF conditions. med./bio.

Published in: Neurosci Lett 2008; 441 (2): 188-192

Aim of study (acc. to author)

To study the effect of different electromagnetic field conditions (900 MHz and 1800 MHz) on the brain activity of men and women.

Background/further details

Previous investigations showed gender-related differences on the EEG during 900 MHz exposure (Papageorgiou et al. 2004) and during 1800 MHz exposure (Nanou et al. 2009).
In the present study (based on the previous data) spectral power coherence was calculated. Spectral power coherence is a measurement parameter that describes whether the EEG energy at a specific location of the brain is distributed among the different frequency bands (delta waves, theta waves, alpha waves, and beta waves) in a coordinated manner (i.e. whether subjects that have higher energy values in one frequency band should be anticipated to have higher energy values in the other frequency bands as well).
Two different groups took part in two separate experiments (900 MHz and 1800 MHz): group 1 consisted of 9 men and 10 women, group 2 consisted of 10 healthy men and 10 healthy women. The subjects performed the memory tests twice (exposed and sham-exposed) with an interval of two weeks.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 900 MHz
Exposure duration: 45 min
Exposure 2: 1,800 MHz
Exposure duration: 45 min

Exposure 1

Main characteristics
Frequency 900 MHz
Type
Exposure duration 45 min
Exposure setup
Exposure source
Chamber Faraday room
Setup antenna fixed at a distance of 20 cm near the right ear
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
power 64 mW mean - - -

Exposure 2

Main characteristics
Frequency 1,800 MHz
Type
Exposure duration 45 min
Exposure setup
Exposure source
Sham exposure A sham exposure was conducted.
Parameters
Measurand Value Type Method Mass Remarks
power 128 mW mean - - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

The results showed that the energy of the delta waves of the EEG did not vary between subjects in such a consistent manner as the energies of the other three EEG frequency bands.
Furthermore, the effect of exposure on the spectral power coherence of the three EEG frequency bands (theta waves, alpha waves, and beta waves) was different for the two genders. The spectral power coherence of males was the same at sham exposure and 900 MHz exposure, but showed a significant drop at 1800 MHz. At the same time females displayed a significant increase of the spectral power coherence at 900 MHz exposure compared to the sham exposure, however no further increase at 1800 MHz exposure.
In comparison of the genders males exhibited a significant higher consistency between the three EEG frequency bands than females at sham exposure, this difference between the genders disappeared at 900 MHz exposure. At 1800 MHz exposure females showed a significant higher consistency than males.
In conclusion, the data showed that the electromagnetic field exposure influenced the spectral power coherence of the EEG and this effect was gender dependend.

Study character:

Study funded by

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