Study type: Medical/biological study (experimental study)

Effects of pulsed electromagnetic fields on cognitive processes - a pilot study on pulsed field interference with cognitive regeneration. med./bio.

Published in: Acta Neurol Scand 2004; 110 (1): 46-52

Aim of study (acc. to author)

To examine effects of exposure to pulsed electromagnetic fields on cognitive performance.

Background/further details

A psycho-physiological test paradigm (auditory discrimination task; determination of auditory order threshold (OT)) was used. Subjects (n=11) had to decide on which side the first of two succeeding stimuli was presented. Inter-stimulus-intervals (ISI) were gradually reduced as long as no mistakes occured; wrong responses led to expansion of the ISI.



Exposure Parameters
Exposure 1: 902 MHz
Modulation type: pulsed
Exposure duration: continuous for 50 min

Exposure 1

Main characteristics
Frequency 902 MHz
Exposure duration continuous for 50 min
Modulation type pulsed
Repetition frequency 217 Hz
Exposure setup
Exposure source
Distance between exposed object and exposure source 4 cm
Chamber electrically shielded room
Setup The exposure took place in the relaxation phase (50 min) during which the participant relaxed on a couch with the mobile phone positioned 4 cm from the left ear.
Additional info Each subject performed the experiment twice with either EMF or sham exposure (double blind) on separate days.
Measurand Value Type Method Mass Remarks
power density 1 mW/m² - - - manufacturer's general information about the mobile phone used - distance not specified

Exposed system:

Methods Endpoint/measurement parameters/methodology

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

Main outcome of study (acc. to author)

The authors found that nine of the 11 test participants (81.8%) showed worse results in their auditory discrimination performance upon field exposure as compared with control conditions. The participants' cognitive performance was impaired after exposure to pulsed electromagnetic fields. With regard to this finding, the authors recommend that the use of cellular phones should be restricted generally and in particular in respect of physical hazard of high-risk groups, e.g. elderly, children and ill people.

Study character:

Study funded by

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