***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background Radio-frequency electromagnetic fields ( RF EMF ) of mobile communication systems are widespread in the living environment , yet their effects on humans are uncertain despite a growing body of literature . Objectives We investigated the influence of a Universal Mobile Telecommunications System ( UMTS ) base station-like signal on well-being and cognitive performance in subjects with and without self-reported sensitivity to RF EMF . Methods We performed a controlled exposure experiment ( 45 min at an electric field strength of 0 , 1 , or 10 V/m , incident with a polarization of 45 ° from the left back side of the subject , weekly intervals ) in a r and omized , double-blind crossover design . A total of 117 healthy subjects ( 33 self-reported sensitive , 84 nonsensitive subjects ) participated in the study . We assessed well-being , perceived field strength , and cognitive performance with question naires and cognitive tasks and conducted statistical analyses using linear mixed models . Organ-specific and brain tissue – specific dosimetry including uncertainty and variation analysis was performed . Results In both groups , well-being and perceived field strength were not associated with actual exposure levels . We observed no consistent condition-induced changes in cognitive performance except for two marginal effects . At 10 V/m we observed a slight effect on speed in one of six tasks in the sensitive subjects and an effect on accuracy in another task in nonsensitive subjects . Both effects disappeared after multiple end point adjustment . Conclusions In contrast to a recent Dutch study , we could not confirm a short-term effect of UMTS base station-like exposure on well-being . The reported effects on brain functioning were marginal and may have occurred by chance . Peak spatial absorption in brain tissue was considerably smaller than during use of a mobile phone . No conclusions can be drawn regarding short-term effects of cell phone exposure or the effects of long-term base station-like exposure on human health Abstract Objective To test whether people who report being sensitive to mobile phone signals have more symptoms when exposed to a pulsing mobile signal than when exposed to a sham signal or a non-pulsing signal . Design Double blind , r and omised , within participants provocation study . Setting Dedicated suite of offices at King 's College London , between September 2003 and June 2005 . Participants 60 “ sensitive ” people who reported often getting headache-like symptoms within 20 minutes of using a global system for mobile communication ( GSM ) mobile phone and 60 “ control ” participants who did not report any such symptoms . Intervention Participants were exposed to three conditions : a 900 MHz GSM mobile phone signal , a non-pulsing carrier wave signal , and a sham condition with no signal present . Each exposure lasted for 50 minutes . Main outcome measures The principal outcome measure was headache severity assessed with a 0 - 100 visual analogue scale . Other outcomes included six other subjective symptoms and participants ' ability to judge whether a signal was present . Results Headache severity increased during exposure and decreased immediately afterwards . However , no strong evidence was found of any difference between the conditions in terms of symptom severity . Nor did evidence of any differential effect of condition between the two groups exist . The proportion of sensitive participants who believed a signal was present during GSM exposure ( 60 % ) was similar to the proportion who believed one was present during sham exposure ( 63 % ) . Conclusions No evidence was found to indicate that people with self reported sensitivity to mobile phone signals are able to detect such signals or that they react to them with increased symptom severity . As sham exposure was sufficient to trigger severe symptoms in some participants , psychological factors may have an important role in causing this condition . Trial registration IS RCT N81432775 [ controlled-trials.com ] Transcranial magnetic stimulation of the dorsolateral prefrontal cortex by single pulses of varying field intensities was used to measure thresholds of individual perception and motor response in three groups of subjects : subjectively electrosensitive people , general population controls with a high burden of complaints related to electromagnetic field ( EMF ) exposure in the literature ( highest decile in complaint burden ) , and general population controls with a low burden of complaints ( lowest decile in complaint burden ) . The major study endpoint was the ability of the subjects to differentiate between real magnetic stimulation and a sham condition . There were no significant differences between groups in the thresholds , neither of detecting the real magnetic stimulus nor in motor response . But the three groups differed significantly in differentiating between stimulation and sham condition , with the subjectively electrosensitive people having the lowest ability to differentiate and the control group with high level of EMF-related complaints having the best ability to differentiate . Differences between groups were mostly due to false alarm reactions in the sham condition reported by subjectively electrosensitives ( SES ) . We found no objective correlate of the self perception of being " electrosensitive . " Overall , our experiment does not support the hypothesis that subjectively electrosensitive patients suffer from a physiological hypersensitivity to EMFs or stimuli . Further research should focus on disposing factors explaining the unspecific sensory hyperresponsiveness of subjectively electrosensitive subjects Abstract In modernen Industriegesellschaften sind zunehmend mehr Menschen vom Phänomen der subjektiven Elektrosensibilität betroffen . Als eines der klinischen Symptome werden häufig Dysästhesien in der Haut berichtet , die - physiologischen Überlegungen folgend - hypothetisch auf Änderungen der Mikrozirkulation zurückgeführt werden können . Diese Hypothese wurde in der vorliegenden Studie überprüft durch Messungen der Mikrozirkulation der Haut des rechten Daumens mittels „ Laser-Doppler-Flowmeter “ ( LDF ) an sieben gesunden Proban und an 3 Personen , die überzeugt waren , unter Elektrosensibilität zu leiden mit und ohne den Einfluss eines zirkulär polarisierten magnetischen Wechselfeldes ( 96 μT , 50 Hz ) . Die Feldexposition führte zu keiner signifikanten Änderung der LDF-Werte . Das LDF-Verhältnis ( „ Feld ein“/Kontrollwert ) betrug 1,03 ± 0,03 . I m Gegensatz dazu verursachten physiologische Stimuli signifikante Änderungen der Mikrozirkulation sowohl bei den Prob and en als auch bei den elektrosensiblen Patienten : Während der Phase einer reaktiven Hyperämie nach Blutleere war das LDF-Verhältnis auf 2,02 ± 0,36 erhöht . Nach Simulation einer Hyperventilation ( zehn tiefe Atemzüge ) war das LDF-Verhältnis vermindert auf 0,63 ± 0,18 . Zusammenfassend lässt sich aussagen , dass ein Einfluß des applizierten Magnetfeldes ( 96 μT , 50 Hz ) auf die Mikrozirkulation der Haut weder bei gesunden Prob and en noch bei elektrosensiblen Personen beobachtet werden konnte . Electromagnetic hypersensitivity ( EH ) is an increasing problem in modern industrial societies . As crawling sensations are frequently mentioned by EH patients alterations in cutaneous microcirculation possibly linked to exposure to magnetic fields might be involved in the development of such sensations and further dysesthesias . In seven healthy volunteers and in three persons convinced to suffer from EH the microcirculation of the right thumb was determined by laser-Doppler-flowmetry ( LDF ) during exposure to circularly polarized 50 Hz magnetic flux densities of 96 mT. During field exposure the LDF values remained constant . The LDF ratio „ field on/field off “ was found to be 1.03 ± 0.03 . In contrast , reactive hyperemia and hyperventilation caused significant changes in the LDF values of volunteers as well as of EH patients .  Following arterial congestion of the forearm microcirculation of the thumb was clearly increased during reperfusion , and the LDF values were elevated up to 2.02 ± 0.36 . 10 deep breaths caused a significant decrease in the LDF values up to 0.63 ± 0.18 . In conclusion , reactive hyperemia and hyperventilation caused clear alterations of cutaneous microcirculation , whereas , 50 Hz magnetic fields had no influence on cutaneous microcirculation OBJECTIVES The purpose of the study was to see whether the results of an earlier study [ ie , that skin symptoms were reduced by reducing electric fields from visual display units ( VDU ) ] could be reproduced or not . In addition , an attempt was made to determine whether eye symptoms and symptoms from the nervous system could be reduced by reducing VDU electric fields . METHODS The study was design ed as a controlled double-blind intervention . The electric fields were reduced by using electric-conducting screen filters .  Forty-two persons completed the study while working at their ordinary job , first 1 week with no filter , then 3 months with an inactive filter  and then 3 months with an active filter ( or in reverse order ) . The inactive filters were identical to the active ones , except that their ground cables were replaced by empty plastic insulation . The inactive filters did not reduce the fields from the VDU . The fields were significantly lower with active filters than with inactive filters . RESULTS Most of the symptoms were statistically significantly less pronounced in the periods with the filters when compared with the period with no filter . This finding can be explained by visual effects and psychological effects . No statistically significant difference in symptom severeness was observed between the period with an inactive filter and the one with an active filter . CONCLUSIONS The study does not support the hypothesis that skin , eye , or nervous system symptoms can be reduced by reducing VDU electric fields The objective was to test whether exposure to radio frequency ( RF ) fields from mobile phones may cause head pain or discomfort and whether it may influence physiological variables in individuals attributing symptoms to mobile phones , but not to electromagnetic fields in general . Seventeen eligible individuals , who experienced these symptoms in an open provocation test , took part in a double-blind , r and omized provocation study with cross-over design . Sixty-five pairs of sham and mobile phone RF exposures were conducted . The increase in pain or discomfort ( visual analogue scales ) in RF sessions was 10.1 and in sham sessions 12.6 ( P = 0.30 ) . Changes in heart rate or blood pressure were not related to the type of exposure ( P : 0.30 - 0.88 ) . The study gave no evidence that RF fields from mobile phones may cause head pain or discomfort or influence physiological variables . The most likely reason for the symptoms is a nocebo effect The aim of the present study was to investigate the effect of exposure to a mobile phone-like radiofrequency ( RF ) electromagnetic field on persons experiencing subjective symptoms when using mobile phones ( MP ) . Twenty subjects with MP-related symptoms were recruited and matched with 20 controls without MP-related symptoms . Each subject participated in two experimental sessions , one with true exposure and one with sham exposure , in r and om order . In the true exposure condition , the test subjects were exposed for 30 min to an RF field generating a maximum SAR(1 g ) in the head of 1 W/kg through an indoor base station antenna attached to a 900 MHz GSM MP . The following physiological and cognitive parameters were measured during the experiment : heart rate and heart rate variability ( HRV ) , respiration , local blood flow , electrodermal activity , critical flicker fusion threshold ( CFFT ) , short-term memory , and reaction time . No significant differences related to RF exposure conditions were detected . Also no differences in baseline data were found between subject groups , except for the reaction time , which was significantly longer among the cases than among the controls the first time the test was performed . This difference disappeared when the test was repeated . However , the cases differed significantly from the controls with respect to HRV as measured in the frequency domain . The cases displayed a shift in low/high frequency ratio towards a sympathetic dominance in the autonomous nervous system during the CFFT and memory tests , regardless of exposure condition . This might be interpreted as a sign of differences in the autonomous nervous system regulation between persons with MP related subjective symptoms and persons with no such symptoms The purpose of this study was to examine the effects of short-term GSM ( Global System for Mobile Communications ) cellular phone base station RF-EMF ( radiofrequency electromagnetic fields ) exposure on psychological symptoms ( good mood , alertness , calmness ) as measured by a st and ardized well-being question naire . Fifty-seven participants were selected and r and omly assigned to one of three different exposure scenarios . Each of those scenarios subjected participants to five 50-min exposure sessions , with only the first four relevant for the study of psychological symptoms . Three exposure levels were created by shielding devices in a field laboratory , which could be installed or removed during the breaks between sessions such that double-blinded conditions prevailed . The overall median power flux densities were 5.2 microW/m(2 ) during " low , " 153.6 microW/m(2 ) during " medium , " and 2126.8 microW/m(2 ) during " high " exposure sessions . For scenario HM and MH , the first and third sessions were " low " exposure . The second session was " high " and the fourth was " medium " in scenario HM ; and vice versa for scenario MH . Scenario LL had four successive " low " exposure sessions constituting the reference condition . Participants in scenarios HM and MH ( high and medium exposure ) were significantly calmer during those sessions than participants in scenario LL ( low exposure throughout ) ( P = 0.042 ) . However , no significant differences between exposure scenarios in the " good mood " or " alertness " factors were obtained . We conclude that short-term exposure to GSM base station signals may have an impact on well-being by reducing psychological arousal 
    Output:
    
No robust evidence could be found to support this theory .
However , the studies included in the review did support the role of the nocebo effect in triggering acute symptoms in IEI-EMF sufferers .
A narrow focus by clinicians or policy makers on bioelectromagnetic mechanisms is therefore , unlikely to help IEI-EMF patients in the long-term