ID Number		1244
Study Type		Human / Provocation
Model		900 MHz (GSM) exposure to adults and children and analysis of cognitive function, headache, fatigue, and hypersensitivity
Details		Human subjects (adults) exposed to 900 MHz GSM signals and tested for cognitive function (attention / vigilance) and working memory performance, the later using the same tasks as in Koivisto, Revonsuo et al (2000), Kovisto, Krause et al (2000) and Krause et al (2000a & 2000b), thus replicating their studies with improved methodology (more accurate dosimetry, statistics, double-blind). The test subjects are also evaluated for subjective symptoms (headache, fatigue and skin symptoms). Both brain hemispheres are exposed to RF (previous behavioural and most EEG studies have limited exposure to the left hemisphere). At an FGF research committee meeting in May 2005, the authors reported no effects in preliminary analysis of 902 MHz RF (CW or PW) on cognitive function as measured by behavioural- and EEG-methodology - in line with the majority of the literature. In a recent published paper, the authors examined differential effects between 900 Mhz (CW, GSM) exposure in the left vs. right hemisphere of the brain in volunteers (n = 36, peak SAR 1.1 W/kg) - prior exposure all performed over right hemisphere. The authors report no statistically significant effects in reaction times or other cognitive endpoints. In other studies, human subjects (24 males, 24 females) were initially exposed (or sham exposed) on the right side of the head to 902 MHz (GSM) from a cellular phone for ~ 1 hour (for the duration of the test) and tested for cognitive performance using a CogniSpeed functional battery of tests. The initial study had the following results: 1) simple rxn time - small decrease in rxn time with RF exposure, p = 0.026, 2) two choice rxn time - no effect, 3) ten choice rxn time - no effect, 4) subtraction task - no effect, 5) subtraction time - decrease in time needed in subtraction task, p = 0.044, 6) sentence verification - no effect, 7) vigilance time - no effect, 8) vigilance score - decrease in false alarms with RF exposure, p = 0.001, 9) shape detection - no effect, 10) object detection - no effect, 11) object familiarity detection - no effect, 12) semantic picture categorization - no effect, 13) semantic word categorization - no effect, 14) object name retrieval - no effect. The score for simple rxn time was 282 +/- 39 (digital RF exposure) and 273 +/- 29 (sham RF exposure) [3.2% decrease], for subtraction time was 245 +/- 148 (digital RF exposure) and 216 +/- 124 (sham RF exposure) [13% decrease], and for vigilance was 517 +/- 48 (digital RF exposure) and 492 +/- 42 (sham RF exposure) [5% decrease]. The authors reported an increase in reaction time in tasks specifically measuring attention. A subsequent study (Bioelectromagnetics (2003) 24:283-288) by the investigators was described as a replication and extension with methodological improvements, and involved multi-center testing and double-blind design using 64 subjects (32 men and 32 women) in two independent laboratories (one in Finland, one in Sweden) and performing a battery of 9 cognitive tasks twice with either RF on or off. In this subsequent study, there was no statistically significant difference and the authors reported no effect of GSM RF exposure on human cognitive function. Similarly, a set of studies was performed in human subjects (24 males, 24 females) in two different laboratories each exposed on the right side of the head to 902 MHz (GSM) from a cellular phone for ~ 30 minutes (for the duration of a test) while they performed an "n-back" memory function test involving visual presentation of single letters on a computer screen in random order and a measure of reaction time and accuracy in recalling the pattern of letter presentation (10 gram peak SAR = 0.683 W/kg in the Finnish lab and 0.990 W/kg in the Swedish lab). An initial report suggested RF exposure might have a slight effect on decreasing reaction time with increased cognitive memory "load". No effect on accuracy with RF exposure at any load level was observed. However, subsequent testing (Bioelectromagnetics 2004, 25(6):452-6) was not successful in replicating these initial observations using a quieter mobile phone, more comfortable exposure conditions, separation of the individual sham and exposed sessions by 24 hours, and a larger sample size, double-blind design, and a second, independent laboratory to conduct the experiment in Sweden. In another study (NeuroReport (2003) 14:2019-20), subjects (n=14) were scanned using PET technology during a visual working memory task and co-exposure to 900 MHz (GSM) RF. Exposure resulted in a decrease in regional cerebral blood flow in the bilateral auditory cortex, but not elsewhere. The authors suggested that the findings might be due to an auditory signal produced by the phone and therefore not indicative of a non-thermal RF effect on brain physiology. Additional studies are ongoing in children (n = 32 aged 10 to 14 years) exposed 40-45 minutes to 900 MHz (GSM). Preliminary results suggest no significant effect of exposure on reaction time tasks or tests of accuracy. Start date April 2002, end date (open).
Findings		No Effects
Status		Completed With Publication
Principal Investigator		Univ. Turku, Finland
Funding Agency		FGF, Germany, Nat'l Res Prog, Finland, Nokia, TEKES
Country		FINLAND
References		Kwon, MS et al. Bioelectromagnetics., (2010) 31:48-55 Haarala, C et al. Bioelectromagnetics, (2007) 28:289-295 Haarala, C et al. Bioelectromagnetics., (2005) 26(S7):S144-S150 Haarala , C et al. Bioelectromagnetics, (2004) 25:452-456 Haarala, C et al. Bioelectromagnetics, (2003) 24:283-288 Koivisto, M et al. Neuroreport, (2000) 11:413-415 Koivisto, M et al. NeuroReport, (2000) 11:1641-1643
Comments		The authors state their results do not confirm Preece (1999) but are consistent with Russo et al (2005)