EFFECTS OF AN ELF (50 HZ, 1 MT) ELECTROMAGNETIC-FIELD (EMF) ON CONCENTRATION IN VISUAL-ATTENTION, PERCEPTION AND MEMORY INCLUDING EFFECTS OF EMF SENSITIVITY

To investigate psychological effects of an extremely low frequency I(E LF)-electromagnetic field (EMF), an experiment with three conditions w as designed. EMF field of 50 Mt and 1 mT accompanied by 45 dB SPL nois e (EMF + noise), noise, and control. A group of 66 subjects (Ss) parti cipated in the control and in one of the experimental conditions. The sequence of conditions (expositions) was balanced. Expositions were do uble-blind (except for the obvious control), lasted 1 h and were separ ated by a I h pause. During exposition Ss (three by three) performed t ests on attention, perception, memory and filled out a psychological q uestionnaire. Statistical analysis (one-tailed probability) showed les s attention (P < 0.05), perception (P < 0.05) and memory performance ( P < 0.1) in Ss exposed to EMF+noise compared with control, whereas for noise versus control no difference was found. Comparing EMF + noise v ersus noise related to control, reduced perception, less memory perfor mance and more discomfort was observed (P<0.1). Dividing Ss according to their self-rated sensitivity to EMF, all differences disappeared in the low sensitivity group (N = 30) and were pronounced in sensitive S s (N = 36). Results indicate an immediate reduction of cognitive perfo rmance in attention, perception and memory performance by a 50 Hz EMF of 1 mT. These effects seem to be modulated by the self-perception of sensitivity to EMF. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.