Study type: Medical/biological study (experimental study)

Examining the effects of electromagnetic fields emitted by GSM mobile phones on human event-related potentials and performance during an auditory task. med./bio.

Published in: Clin Neurophysiol 2004; 115 (1): 171-178

Aim of study (acc. to author)

To explore the sensitivity of auditory event-related potentials to electromagnetic emissions.

Background/further details

The current study exposed subjects while they performed tasks, and employed a mobile phone with a substantial and consistent power output. In order to study alterations in sensory processing that may be produced by electromagnetic field exposure, the event-related potential parameters were assessed during an auditory oddball task.

Endpoint

Exposure

Exposure Parameters
Exposure 1: 894.6 MHz
Modulation type: pulsed
Exposure duration: continuous for 1 h
  • power: 2 W peak value
  • power: 250 mW mean
  • SAR: 0.87 W/kg unspecified (unspecified) (at the head)

Exposure 1

Main characteristics
Frequency 894.6 MHz
Type
Exposure duration continuous for 1 h
Modulation
Modulation type pulsed
Pulse width 576 µs
Duty cycle 12.5 %
Repetition frequency 217 Hz
Exposure setup
Exposure source
Setup Participants were seated in a comfortable chair with an electro-cap fitted (comprising 62 tin electrodes). A mobile phone in a cradle was placed over the right temporal region in a normal use position. Audio circuits were disabled and a padding was placed between the handset and its casing to prevent any acoustic or thermal cues. The mobile phone was set via lap-top to a nominal mean power output of 250 mW.
Additional info There were two sessions one week apart, each with real or sham exposure for half of the participants in single-blind, counterbalanced, crossover conditions.
Parameters
Measurand Value Type Method Mass Remarks
power 2 W peak value - - -
power 250 mW mean - - -
SAR 0.87 W/kg unspecified estimated unspecified at the head

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

The results suggest that mobile phone radiation may affect neural activity, particularly in proximity to the phone, however caution should be applied due to the small sample size. N100 amplitude decreased, N100 latency shortened and P300 latency was delayed during exposure compared to sham exposure. Effects were greatest over right hemisphere and midline sites (closest to the active mobile phone). Reaction time increased in the exposure relative to sham exposure condition and no difference in accuracy was found.

Study character:

Study funded by

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