Influence of a 902.4 MHz GSM signal on the human visual system: Investigation of the discrimination threshold

For the last two decades, a large number of studies have investigated the effects of mobile phone radiation on the human brain and cognition using behavioral or neurophysiological measurements. This review evaluated previous findings with respect to study design and data analysis. Provocation studies found no evidence of subjective symptoms attributed to mobile phone radiation, suggesting psychological reasons for inducing such symptoms in hypersensitive people. Behavioral studies previously reported improved cognitive performance under exposure, but it was likely to have occurred by chance due to multiple comparisons. Recent behavioral studies and replication studies with more conservative statistics found no significant effects compared with original studies. Neurophysiological studies found no significant effects on cochlear and brainstem auditory processing, but only inconsistent results on spontaneous and evoked brain electrical activity. The inconsistent findings suggest possible false positives due to multiple comparisons and thus replication is needed. Other approaches such as brain hemodynamic response measurements are promising but the findings are few and not yet conclusive. Rigorous study design and data analysis considering multiple comparisons and effect size are required to reduce controversy in this important field of research.

Section: Cognitive Performancementioning

confidence: 97%

Effects of mobile phone electromagnetic fields: Critical evaluation of behavioral and neurophysiological studies

Kwon

Hämäläinen

2010

“…One of the critical organs that might be damaged by RF‐EMF is the eye, due to its relative proximity to the radiation source during normal mobile phone use. Many studies focused on possible injuries of monkey, human, or rabbit eyes and the visual system in response to EMF exposure of various intensities, frequencies, and modulations [Lu et al, ; Schmid et al, ; Irlenbusch et al, ]. Cornea and lens of the eye are clearly damaged by excessive temperature rise induced by high specific absorption rates (SAR) [Carpenter, ; Kues et al, ; Kues and Monahan, ].…”

Section: Introductionmentioning

confidence: 99%

“…Changes in various components of the retinal ERG were reported by Yee [] and Lim et al [] in rabbit and human retinas at SAR values of 3.6 and 4 W/kg. No influences were observed on various parameters of human visual perception [Schmid et al, ] and on human discrimination threshold [Irlenbusch et al, ] with 1970 MHz and 902.4 MHz EMF, respectively, both with SAR values below 1 W/kg.…”

Section: Introductionmentioning

confidence: 99%

No influence of acute RF exposure (GSM‐900, GSM‐1800, and UMTS) on mouse retinal ganglion cell responses under constant temperature conditions

Ahlers

Ammermüller

2013

Possible non-thermal effects of radio frequency electromagnetic fields (RF-EMF) on retinal ganglion cells were studied in vitro under conditions of constant temperature. Isolated mouse retinae were exposed to GSM-900, GSM-1800, and universal mobile telecommunication system (UMTS) RF-EMF applying specific absorption rates (SAR) of 0 (sham), 0.02, 0.2, 2, and 20 W/kg. Temperature was kept constant within ±0.5 to 1 °C for GSM-900 and ±0.5 °C for GSM-1800 and UMTS. Responses of retinal ganglion cells to light stimuli of three intensities (0.5, 16, and 445 lx) were recorded before, during, and up to 35 min after exposure. Experiments were performed under double-blind conditions. Changes in light responses during and after exposure were determined for each condition (RF-EMF; SAR value; light intensity) with respect to the responses before exposure, respectively. Changes were calculated using the Euclidian distance of the n-dimensional response vectors, respectively. Some changes already occurred during sham (0 W/kg) exposure, reflecting the intrinsic variability in retinal ganglion cell responses. Comparison of the distance values from sham exposure with those from actual exposure yielded no significant differences. In addition, linear regression analysis of the distance values versus SAR values yielded no consistent dependence of light response changes. From these results we conclude that RF-EMF exposure at three mobile phone frequencies (GSM-900, GSM-1800, UMTS) and SARs up to 20 W/kg has no acute effects on retinal ganglion cell responses under constant temperature conditions.

“…The vast majority of these studies examined the effects of Global System for Mobile Communications (GSM)-like signals [Hamblin et al, 2006;Wilen et al, 2006;Fritzer et al, 2007;Haarala et al, 2007;Irlenbusch et al, 2007;Krause et al, 2007;Regel et al, 2007a,b;Barth et al, 2008;Cinel et al, 2008;Curcio et al, 2008;Kleinlogel et al, 2008;Luria et al, 2009;Wiholm et al, 2009], whereas only a few analysed the impact of Wideband Code-Division Multiple Access/3rd Generation Universal Mobile Telecommunications System (WCDMA/3G UMTS) handset signals on cognitive function [Schmid et al, 2005;Kleinlogel et al, 2008;Unterlechner et al, 2008].…”

Section: Introductionmentioning

confidence: 99%

“…Several studies on the possible effects of RF-EMF of GSM mobile phones on cognition did not find any difference in performance measures between real and sham exposure [Hladky et al, 1999;Croft et al, 2002;Haarala et al, 2003Haarala et al, , 2004Haarala et al, , 2007Hinrichs and Heinze, 2004;Besset et al, 2005;Russo et al, 2006;Cinel et al, 2007Cinel et al, , 2008Fritzer et al, 2007;Irlenbusch et al, 2007;Curcio et al, 2008;Kleinlogel et al, 2008]. On the other hand, there are an almost equal number of studies reporting effects on cognitive functions, however, the effects are not consistent.…”

Section: Introductionmentioning

confidence: 99%

Effects of exposure to electromagnetic fields emitted by GSM 900 and WCDMA mobile phones on cognitive function in young male subjects

Sauter¹,

Dorn²,

Bahr³

et al. 2010

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.