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Background: The World Health Organization (WHO) is currently assessing the potential health effects of exposure to radiofrequency electromagnetic fields (RF-EMFs) in the general and working population. Related to one such health effect, there is a concern that RF-EMFs may affect cognitive performance in humans. The systematic review (SR) aims to identify, summarize and synthesize the evidence base related to this question. Here, we present the protocol for the planned SR., Objectives: The main objective is to present a protocol for a SR which will evaluate the associations between short-term exposure to RF-EMFs and cognitive performance in human experimental studies., Data Sources: We will search the following databases: PubMed, Embase, Web of Science, Scopus, and the EMF-Portal. The reference lists of included studies and retrieved review articles will be manually searched., Study Eligibility and Criteria: We will include randomized human experimental studies that assess the effects of RF-EMFs on cognitive performance compared to no exposure or lower exposure. We will include peer-reviewed articles of any publication date in any language that report primary data., Data Extraction and Analysis: Data will be extracted according to a pre-defined set of forms developed and piloted by the review author team. To assess the risk of bias, we will apply the Rating Tool for Human and Animal Studies developed by NTP/OHAT, supplemented with additional questions relevant for cross-over studies. Where sufficiently similar studies are identified (e.g. the heterogeneity concerning population, exposure and outcome is low and the studies can be combined), we will conduct random-effects meta-analysis; otherwise, we will conduct a narrative synthesis., Assessment of Certainty of Evidence: The certainty of evidence for each identified outcome will be assessed according to Grading of Recommendations Assessment, Development, and Evaluation (GRADE). Performing the review according to this protocol will allow the identification of possible effects of RF-EMFs on cognitive performance in humans. The protocol has been registered in PROSPERO, an open-source protocol registration system, to foster transparency., (Copyright © 2021. Published by Elsevier Ltd.)

Background: Although there are several human experimental studies on short-term effects of radiofrequency electromagnetic fields (RF-EMF) on sleep, the role of effect modification by sex or age in this context has not yet been considered. In an earlier study, we observed sex differences in RF-EMF effects in elderly subjects. The present study investigated possible RF-EMF effect modifications by age in men., Methods: Data available for the present analysis come from three double-blind, randomized cross-over studies, in which effects of different RF-EMF exposure signals on sleep were investigated in young [sample 1: 25.3 (mean) ± 2.6 (SD) years; sample 2: 25.4 ± 2.6 years; n = 30, respectively] and older (69.1 ± 5.5 years; n = 30) healthy male volunteers. Studies comprised a screening/adaptation night followed by nine experimental nights at two-week intervals. RF-EMF exposure effect modifications by age were analysed for two different exposure signals (GSM900 at 2 W/kg, TETRA at 6 W/kg), each compared to a sham exposure. Polysomnography, during which the exposure signals were delivered by a head worn antenna, as well as sleep staging were performed according to the AASM standard. Four subjective and 30 objective sleep parameters were statistically analysed related to possible RF-EMF effects., Results: Comparisons of sleep parameters observed under sham exposure revealed highly pronounced physiological differences between young and elderly men. A consistent exposure effect in both age groups was found for a shorter latency to persistent sleep under TETRA exposure reflecting a sleep-promoting effect. Exposure effect modifications by age were observed for two of the four self-reported sleep parameters following GSM900 exposure and for arousals during REM sleep under TETRA exposure., Conclusions: As effects of a short-term all-night RF-EMF exposure on sleep occurred only sporadically in young and elderly men, it seems that age doesn't matter in this respect. However, as long as there are no corresponding data from young healthy women that would allow a comparison with the data from elderly women, this assumption cannot be conclusively verified. Nevertheless, the present results are not indicative of any adverse health effects., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: The use of wireless telecommunication systems such as wireless fidelity (Wi-Fi)-enabled devices has steadily increased in recent years. There are persistent concerns that radiofrequency electromagnetic field (RF-EMF) exposure might affect health. Possible effects of RF-EMF exposure on human sleep were examined with regard to mobile phones and base stations, but not with regard to Wi-Fi exposure., Objectives: The present double-blind, sham-controlled, randomized, fully counterbalanced cross-over study addressed for the first time the question whether a whole night Wi-Fi exposure has an effect on sleep., Methods: Thirty-four healthy young male subjects (mean ± SD: 24.1 ± 2.9 years) spent five nights in the sleep laboratory. A screening and adaptation night was followed by two experimental nights. Each of the experimental nights was preceded by a baseline night. Sleep was evaluated at the subjective level by a questionnaire and at the objective level (macro- and microstructure) by polysomnography. Either 2.45 GHz Wi-Fi (max psSAR10g of 6.4 mW/kg) or sham signals were delivered by a newly developed head exposure facility., Results: Results showed no statistically significant acute effects of a whole-night Wi-Fi exposure on subjective sleep parameters as well as on parameters characterizing the macrostructure of sleep. Analyses of the microstructure of sleep revealed a reduction in global EEG power in the alpha frequency band (8.00-11.75 Hz) during NREM sleep under acute Wi-Fi exposure compared to sham., Discussion: The results of the present human experimental study are well in line with several other neurophysiological studies showing that acute RF-EMF exposure has no effect on the macrostructure of sleep. The slight physiological changes in EEG power observed under Wi-Fi exposure are neither reflected in the subjective assessment of sleep nor at the level of objective measurements. The present results are not indicative of a sleep disturbing effect of Wi-Fi exposure., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier GmbH. All rights reserved.)

Background: Results from human experimental studies investigating possible effects of radiofrequency electromagnetic fields (RF-EMF) on sleep are heterogeneous. So far, there is no study on possible sex-differences in RF-EMF effects., Objectives: The present study aimed at analyzing differences in RF-EMF effects on the macrostructure of sleep between healthy elderly males and females., Methods: With a double-blind, randomized, sham-controlled cross-over design effects of two RF-EMF exposures (GSM900 and TETRA) on sleep were investigated in samples of 30 elderly healthy male and 30 healthy elderly female volunteers. Participants underwent each of the three exposure conditions on three occassions following an individually randomized order resulting in a total of nine study nights per participant. Exposure was delivered for 30 min prior to sleep and for the whole night (7.5 h) by a head worn antenna specifically designed for the projects. The peak spatial absorption rate averaged over time in head tissues (psSAR10g) was 6 W/kg for TETRA and 2 W/kg for GSM900. Thirty variables characterising the macrostructure of sleep and arousals as well as four subjective sleep variables were considered for statistical analyses., Results: Multivariate analyses revealed that exposure to GSM900 and/or TETRA resulted in a significant reduction in arousals, a shorter latency to sleep stage N3, and a shorter self-reported time awake after sleep in both males and females. Exposure effects depending on sex (significant interactions) were observed. Latency to sleep stage R was shorter in females and tended to be longer in males under both exposures. Latency to stage N3 was shorter in females under TETRA exposure and almost not affected in males. The time awake within the sleep period under TETRA exposure was shorter in females and only slightly longer in males. Under GSM exposure, the self-rated total sleep time tended to be longer in females and to be shorter in males. Finally, the number of awakenings was lower only in females and tended to be higher in males under GSM exposure., Discussion: With regard to RF-EMF effects on human sleep it seems that gender matters since GSM900 and TETRA led to significantly more exposure effects in females. Regardless of gender, none of the observed changes is indicative of a sleep disturbing effect of RF-EMF exposure. Observed effects might be mediated by skin related thermoregulatory mechanisms., (Copyright © 2020 Elsevier Inc. All rights reserved.)

A new head exposure system for double-blind provocation studies investigating possible effects of 2.45 GHz Wi-Fi exposure on human sleep was developed and dosimetrically analyzed. The exposure system includes six simultaneously radiating directional antennas arranged along a circle (radius 0.6 m) around the test subject's head, and enables a virtually uniform head exposure, i.e. without any preferred direction of incidence, during sleep. The system is fully computer-controlled and applies a real wireless local area network (WLAN) signal representing different transmission patterns as expected in real WLAN scenarios, i.e. phases of "beacon only" as well as phases of different data transmission rates. Sham and verum are applied in a double-blind crossover study design and all relevant exposure data, i.e. forward and reverse power at all six antenna inputs, are continuously recorded for quality control. For a total antenna input power (sum of all antennas) of 220 mW, typical specific absorption rate (SAR) in cortical brain regions is approximately 1-2 mW/kg (mass average SAR over respective brain region), which can be seen as a realistic worst-case exposure level in real WLAN scenarios. Taking into account variations of head positions during the experiments, the resulting exposure of different brain regions may deviate from the given average SAR levels up to 10 dB. Peak spatial 10 g average SAR in all brain and all head tissues is between 1.5-3.5 and 10.4-25 mW/kg, respectively. Bioelectromagnetics. © 2020 Bioelectromagnetics Society., (© 2020 Bioelectromagnetics Society.)

The results of studies on possible effects of radiofrequency electromagnetic fields (RF-EMFs) on human waking electroencephalography (EEG) have been quite heterogeneous. In the majority of studies, changes in the alpha-frequency range in subjects who were exposed to different signals of mobile phone-related EMF sources were observed, whereas other studies did not report any effects. In this review, possible reasons for these inconsistencies are presented and recommendations for future waking EEG studies are made. The physiological basis of underlying brain activity, and the technical requirements and framework conditions for conducting and analyzing the human resting-state EEG are discussed. Peer-reviewed articles on possible effects of EMF on waking EEG were evaluated with regard to non-exposure-related confounding factors. Recommendations derived from international guidelines on the analysis and reporting of findings are proposed to achieve comparability in future studies. In total, 22 peer-reviewed studies on possible RF-EMF effects on human resting-state EEG were analyzed. EEG power in the alpha frequency range was reported to be increased in 10, decreased in four, and not affected in eight studies. All reviewed studies differ in several ways in terms of the methodologies applied, which might contribute to different results and conclusions about the impact of EMF on human resting-state EEG. A discussion of various study protocols and different outcome parameters prevents a scientifically sound statement on the impact of RF-EMF on human brain activity in resting-state EEG. Further studies which apply comparable, standardized study protocols are recommended. Bioelectromagnetics. 2019;40:291-318. © 2019 The Authors. Bioelectromagnetics Published by Wiley Periodicals, Inc., (© 2019 The Authors. Bioelectromagnetics Published by Wiley Periodicals, Inc.)

Background: Studies on effects of radio frequency-electromagnetic fields (RF-EMF) on the macrostructure of sleep so far yielded inconsistent results. This study investigated whether possible effects of RF-EMF exposure differ between individuals., Objective: In a double-blind, randomized, sham-controlled cross-over study possible effects of electromagnetic fields emitted by pulsed Global System for Mobile Communications (GSM) 900 and Wideband Code-Division Multiple Access (WCDMA)/Universal Mobile Telecommunications System (WCDMA/UMTS) devices on sleep were analysed., Methods: Thirty healthy young men (range 18-30 years) were exposed three times per exposure condition while their sleep was recorded. Sleep was evaluated according to the American Academy of Sleep Medicine standard and eight basic sleep variables were considered., Results: Data analyses at the individual level indicate that RF-EMF effects are observed in 90% of the individuals and that all sleep variables are affected in at least four subjects. While sleep of participants was affected in various numbers, combinations of sleep variables and in different directions, showing improvements but also deteriorations, the only consistent finding was an increase of stage R sleep under GSM 900MHz exposure (9 of 30 subjects) as well as under WCDMA/UMTS exposure (10 of 30 subjects)., Conclusions: The results underline that sleep of individuals can be affected differently. The observations found here may indicate an underlying thermal mechanism of RF-EMF on human REM sleep. Nevertheless, the effect of an increase in stage R sleep in one third of the individuals does not necessarily indicate a disturbance of sleep., (Copyright © 2015 Elsevier Inc. All rights reserved.)

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., (Copyright © 2010 Wiley-Liss, Inc.)

In the present double-blind, randomized, sham-controlled cross-over study, possible effects of electromagnetic fields emitted by Global System for Mobile Communications (GSM) 900 and Wideband Code-Division Multiple Access (WCDMA)/Universal Mobile Telecommunications System (UMTS) cell-phones on the macrostructure of sleep were investigated in a laboratory environment. An adaptation night, which served as screening night for sleep disorders and as an adjustment night to the laboratory environment, was followed by 9 study nights (separated by a 2-week interval) in which subjects were exposed to three exposure conditions (sham, GSM 900 and WCDMA/UMTS). The sample comprised 30 healthy male subjects within the age range 18-30 years (mean ± standard deviation: 25.3 ± 2.6 years). A cell-phone usage at maximum radio frequency (RF) output power was simulated and the transmitted power was adjusted in order to approach, but not to exceed, the specific absorption rate (SAR) limits of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) guidelines for general public exposure (SAR(10g) = 2.0 W kg(-1)). In this study, possible effects of long-term (8 h) continuous RF exposure on the central nervous system were analysed during sleep, because sleep is a state in which many confounding intrinsic and extrinsic factors (e.g. motivation, personality, attitude) are eliminated or controlled. Thirteen of 177 variables characterizing the initiation and maintenance of sleep in the GSM 900 and three in the WCDMA exposure condition differed from the sham condition. The few significant results are not indicative of a negative impact on sleep architecture. From the present results there is no evidence for a sleep-disturbing effect of GSM 900 and WCDMA exposure., (© 2010 European Sleep Research Society.)

Objectives: The aim of the present double-blind, sham-controlled, balanced randomized cross-over study was to disentangle effects of electromagnetic fields (EMF) and non-EMF effects of mobile phone base stations on objective and subjective sleep quality., Methods: In total 397 residents aged 18-81 years (50.9% female) from 10 German sites, where no mobile phone service was available, were exposed to sham and GSM (Global System for Mobile Communications, 900 MHz and 1,800 MHz) base station signals by an experimental base station while their sleep was monitored at their homes during 12 nights. Participants were randomly exposed to real (GSM) or sham exposure for five nights each. Individual measurement of EMF exposure, questionnaires on sleep disorders, overall sleep quality, attitude towards mobile communication, and on subjective sleep quality (morning and evening protocols) as well as objective sleep data (frontal EEG and EOG recordings) were gathered., Results: Analysis of the subjective and objective sleep data did not reveal any significant differences between the real and sham condition. During sham exposure nights, objective and subjective sleep efficiency, wake after sleep onset, and subjective sleep latency were significantly worse in participants with concerns about possible health risks resulting from base stations than in participants who were not concerned., Conclusions: The study did not provide any evidence for short-term physiological effects of EMF emitted by mobile phone base stations on objective and subjective sleep quality. However, the results indicate that mobile phone base stations as such (not the electromagnetic fields) may have a significant negative impact on sleep quality., ((c) 2010 Wiley-Liss, Inc.)

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Background Studies have shown that exposure to radiofrequency electromagnetic fields (RF-EMF) in the mobile communication frequency range may induce physiological modifications of both spontaneous as well as event-related human electroencephalogram. So far, there are very few peer-reviewed studies on effects of Terrestrial Trunked Radio (TETRA), which is a digital radio communication standard used by security authorities and organizations in several European countries, on the central nervous system. Objectives To analyze the impact of simulated TETRA handset signals at 385 MHz on slow cortical potentials (SCPs). Methods 30 young healthy males (25.2±2.7 years) were exposed in a double-blind, counterbalanced, cross-over design to one of three exposure levels (TETRA with 10 g averaged peak spatial SAR: 1.5 W/kg, 6.0 W/kg and sham). Exposure was conducted with a body worn antenna (especially designed for this study), positioned at the left side of the head. Subjects had 9 test sessions (three per exposure condition) in which three SCPs were assessed: SCP related to a clock monitoring task (CMT), Contingent negative variation (CNV) and Bereitschaftspotential (BP). Results Neither behavioral measures nor the electrophysiological activity was significantly affected by exposure in the three investigated SCP paradigms. Independent of exposure, significant amplitude differences between scalp regions could be observed for the CMT-related SCP and for the CNV. Conclusions The present results reveal no evidence of RF-EMF exposure-dependent brain activity modifications investigated at the behavioral and the physiological level. [ABSTRACT FROM AUTHOR]