The influence of pulsed radiofrequency (RF) electromagnetic fields of digital GSM mobile phones on working memory in healthy subjects were studied. Memory load was varied from 0 to 3 items in an n-back task. Each subject was tested twice within a single session, with and without the RF exposure (902 MHz, 217 Hz). The RF field speeded up response times when the memory load was three items but no effects of RF were observed with lower loads. The results suggest that RF fields have a measurable effect on human cognitive performance and encourage further studies on the interactions of RF fields with brain function.
1Centre for Cognitive Neuroscience, University of Turku, FIN-20014, Turku
2Department of Neurology, University of Turku, FIN-20014, Turku
3Department of Philosophy, University of Turku, FIN-20014, Turku
4Department of Psychology, University of Turku, FIN-20014, Turku
5Department of Psychology, Åbo Akademi University, Finland
6Corresponding Author and Address: Mika Koivisto, Centre for Cognitive Neuroscience, University of Turku, FIN-20014, Turku
Acknowledgements: This study was supported by the University of Turku, and Nokia. H.H. (project 37873), C.M.K. (projects 7338 and 42536), M.L (project 43301) and A.R. (projects 36106 and 45704) were supported by the Academy of Finland.
Received 15 February 2000; accepted 13 March 2000