title: Effects of exposure to electromagnetic fields emitted by GSM 900 and WCDMA mobile phones on cognitive function in young male subjects.
abstract: Results of studies on the possible effects of electromagnetic fields emitted by mobile phones on cognitive functions are contradictory, therefore, possible effects of long-term (7 h 15 min) electromagnetic field (EMF) exposure to handset-like signals of Global System for Mobile Communications (GSM) 900 and Wideband Code-Division Multiple Access (WCDMA) on attention and working memory were studied. The sample comprised 30 healthy male subjects (mean ± SD: 25.3 ± 2.6 years), who were tested on nine study days in which they were exposed to three exposure conditions (sham, GSM 900 and WCDMA) in a randomly assigned and balanced order. All tests were presented twice (morning and afternoon) on each study day within a fixed timeframe. Univariate comparisons revealed significant changes when subjects were exposed to GSM 900 compared to sham, only in the vigilance test. In the WCDMA exposure condition, one parameter in the vigilance and one in the test on divided attention were altered compared to sham. Performance in the selective attention test and the n-back task was not affected by GSM 900 or WCDMA exposure. Time-of-day effects were evident for the tests on divided and selective attention, as well as for working memory. After correction for multiple testing, only time-of-day effects remained significant in two tests, resulting in faster reactions in the afternoon trials. The results of the present study do not provide any evidence of an EMF effect on human cognition, but they underline the necessity to control for time of day.
authors.affiliation: Competence Centre of Sleep Medicine, Charité-Universitaetsmedizin Berlin, Berlin, Germany. cornelia.sauter@charite.de
authors.forename: Cornelia
authors.initials: C
authors.lastname: Sauter
authors.forename: Hans
authors.initials: H
authors.lastname: Dorn
authors.forename: Achim
authors.initials: A
authors.lastname: Bahr
authors.forename: Marie-Luise
authors.initials: ML
authors.lastname: Hansen
authors.forename: Anita
authors.initials: A
authors.lastname: Peter
authors.forename: Malek
authors.initials: M
authors.lastname: Bajbouj
authors.forename: Heidi
authors.initials: H
authors.lastname: Danker-Hopfe
mesh_terms: D000293:Adolescent; D000328:Adult; D001143:Arousal / Q000502:physiology / Q000528:radiation effects; D001288:Attention / Q000502:physiology / Q000528:radiation effects; D040421:Cell Phone; D003071:Cognition / Q000502:physiology* / Q000528:radiation effects*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004574:Electromagnetic Fields / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology / Q000528:radiation effects; D013997:Time Factors; D055815:Young Adult