Bioelectromagnetics 29:237 ^ 241 (2008) Brief Communication Psychomotor Performance is Not Influenced by Brief Repeated Exposures to Mobile Phones G. Curcio, 1,2 * E. Valentini, 1 F. Moroni, 1 M. Ferrara, 3 L. De Gennaro, 1 and M. Bertini 1 1 Dipartimento di Psicologia, Universita' di Roma‘‘La Sapienza’’, Roma, Italy 2 Dipartimento di Neuroscienze Cliniche, Universita' Campus Bio-medico di Roma, Roma, Italy 3 Dipartimento di Medicina Interna e Salute Pubblica, Universita' di L’Aquila, L’Aquila, Italy The present study investigated the presence of a cumulative effect of brief and repeated exposures to a GSM mobile phone (902.40 MHz, 217 Hz modulated; peak power of 2 W; average power of 0.25 W; SAR ¼ 0.5 W/kg) on psychomotor functions. To this end, after each of 3 15-min exposures, both an acoustic simple reaction time task (SRTT) and a sequential finger tapping task (SFTT) were administered to 24 subjects. The present study was unable to detect the cumulative effects of brief and repeated EMF exposure on human psychomotor performance, although there was a non-statistical trend to shorter reaction times. In summary, these data show an absence of effects with these particular exposure conditions; however, possible cognitive effects induced by different signal characteristics cannot be excluded. Bioelectromagnetics 29:237–241, 2008. ß 2007 Wiley-Liss, Inc. Key words: GSM; performance; electromagnetic fields; behavioral effects Over the last 10 years the exponential increase in mobile phone (MP) availability has given rise to questions about possible health effects on users. Indeed, since a discrete amount of radiofrequencies (RF) emitted by MP is absorbed through the skull and reaches the brain [Schonborn et al., 1998], it is possible to hypothesize a physiological interaction between these very low RF electromagnetic fields (EMFs) and human cerebral activity, with a consequent potential influence on human performance. Several research groups have recently observed an increase in performance speed measures due to RF exposure, while accuracy indices seemed not to be particularly sensitive to MP exposure [Koivisto et al., 2000; Edelstyn and Oldershaw, 2002; Curcio et al., 2004]. However, some of the authors who originally observed these facilitatory effects were unable to replicate earlier findings in successive studies characterized by methodological improvements (i.e., double-blind designs, multicentre protocols). Furthermore, one of the most recent and statistically powerful studies [Russo et al., 2006] showed no significant effects of both Global System for Mobile Communication (GSM) and unmodulated continuous signal (CW) exposure on attention measures in adults. A very important and not yet extensively investi- gated issue concerns the time course of the possible influence of RF irradiation [Cook et al., 2006]. At first, Edelstyn and Oldershaw [2002] reported the existence of a ‘‘fast-acting effect’’ since a facilitatory effect on performance was observed after only 15 min of exposure. Subsequently, other authors claimed that at least 25–30 min of exposure would be needed to highlight a clear facilitation in psychomotor and physiological measures [Koivisto et al., 2000; Curcio et al., 2004]. Moreover, almost all the studies carried out until now have investigated acute effects of single exposures to variable EMF intensities. In fact, the only study dealing with the effects of single daily exposures (2 h for a period of 28 days) to a GSM signal on behavioral and cognitive functioning showed an overall absence of significant effects [Besset et al., 2005]. In view of this, the aim of the present study was to evaluate the effect induced by short (15 min) and repeated (3 times in a period of 85 min) exposures to a ß 2007 Wiley-Liss,Inc. —————— *Correspondence to: G. Curcio, Dipartimento di Psicologia, Universita ` di Roma ‘‘La Sapienza’’, Via dei Marsi, 78, I-00185 Roma, Italy. E-mail: giuseppe.curcio@uniroma1.it Received for review 21 March 2007; Final revision received 24 October 2007 DOI 10.1002/bem.20393 Published online 28 December 2007 in Wiley InterScience (www.interscience.wiley.com).