ID Number		256
Study Type		Human / Provocation
Model		900 (GSM) exposure to humans and analysis of cognitive function
Details		Regular mobile phone users including both self reported electro-magnetic hypersensitive (EHS) (n = 23) as well as non-EHS controls (n = 19) were recruited for the study. EHS was defined as experiencing at least one occurrence of headache, dizziness or other kind of pain or discomfort in the head attributed to the use of mobile phones. Respondents were excluded if they experienced any symptoms with electrical equipment other than mobile phones, had a current medical or psychological illness, history of brain injury, ongoing medication, sleep disorders, hypertension, or pregnancy. Cognitive function was determined by using a virtual Morris Water Task with a double blind cross-over provocation design. Performance was assessed either before or after a 2 ½ hour exposure to an 884 MHz GSM signal using a panel antenna system designed by Niels Kusters group at ETH that exposed the left side of the head. Modeling predicted a peak 10 gram SAR in the head of 1.95 W/kg during full rate GSM transmission, although the transmitted signal was randomly interspersed with a reduced bursting rate GSM mode called discontinuous transmission (DTx) that resulted in a peak 10 gram SAR of 0.23 W/kg. The resulting signal contained periods of full rate GSM (average duration 11 seconds) and DTx (average duration 5 seconds) that resulted in a total time-averaged SAR of 1.4 W/kg. RESULTS: The authors report EHS individuals (which, prior to exposure, demonstrated on average a longer distance traveled to reach the target as compared with non-hypersensitive controls) improved their performance with exposure (i.e., shorter distance traveled) and reached a level comparable with the non-hypersensitive control. The non-hypersensitive subjects showed no such improvement with RF exposure. The authors suggest the EHS subjects may have been more stressed by the laboratory conditions, bringing their baseline pre-exposure performance down. The GSM exposure may have either relaxed some of this stress or otherwise increased biological arousal mechanisms that improved attention. Although the authors conclude that the findings & are subtle and may only be detected in subjects who report being sensitive to mobile phone use, they suggest & some enhancing effects of GSM exposure on spatial memory may occur. Interestingly, Table 1 in the paper demonstrates that the EHS group had a higher percentage of females and tended to use the mobile phone more often per day than the non-EHS group. While the authors also note that females generally under-perform in spatial memory tasks as compared with males, and that this may have affected the baseline performance between the two groups, they do not think it is sufficient to explain the observed improvement in the EHS group after GSM exposure. They conclude Given the [prior] findings of direct effects of RF exposure on brain physiology, the present results may conceivably be attributable to direct effects of RF exposure on the neural or cognitive systems supporting human navigation
Findings		Effects
Status		Completed With Publication
Principal Investigator		Karolinska Institute, Sweden - bengt.arnetz@pubcare.uu.se
Funding Agency		EU, MMF
Country		SWEDEN
References		Wiholm, C et al. Bioelectromagnetics, (2009) 30:59-65
Comments		Part of Perform C studies to investigate questions of human subjective complaints following cell phone exposure.