|
Exposure to the radiofrequency fields generated by mobile phones does not cause head pain or increase blood pressure, according to a Norwegian study.
|
Exposure to the radiofrequency fields generated by mobile phones does not cause head pain or increase blood pressure, according to a Norwegian study.
Instead, people who experience such symptoms do so because they expect that they will occur, the findings suggest.
Dr Gunnhild Oftedal and associates at the Norway University of Science and Technology in Trondheim recruited 17 subjects who "regularly experienced pain or discomfort in the head during or shortly after mobile phone calls lasting between 15 and 30 minutes."
The participants were tested during mobile phone radiofrequency exposure andshamexposure, without knowing which session was which. Each session lasted 30 minutes, and 65 pairs of trials were conducted.
As reported in the medical journal Cephalalgia, the subjects said they felt an increase in pain or discomfort during 68 per cent of all trials. The degree of symptoms was not associated with the order of trials.
The researchers observed no statistically significant correlations between actual exposures and the subjects' reports of symptom severity, and no effects of exposure on changes in heart rate or blood pressure.
Oftedal's team concludes that the most likely explanation for the headaches and discomfort reported by the subjects "is that the symptoms are due to negative expectations."
(Reuters)
|
挪威一項(xiàng)最新研究表明,置身手機(jī)所產(chǎn)生的射頻場(chǎng)不會(huì)導(dǎo)致頭痛或血壓升高。
研究結(jié)果表明,出現(xiàn)這些癥狀的人主要是因?yàn)樗麄冏约河X得會(huì)出問(wèn)題。
挪威科技大學(xué)(位于特隆赫姆)的甘赫爾德·奧弗泰德爾博士和他的同事共招募了17名研究對(duì)象,這些人“經(jīng)常在打15至30分鐘電話的過(guò)程中或剛打完后出現(xiàn)頭痛或頭部不適癥狀”。
研究人員讓研究對(duì)象在不知情的情況下,分別置于射頻場(chǎng)及假性輻射中。每一環(huán)節(jié)持續(xù)30分鐘,共進(jìn)行了65組試驗(yàn)。
在醫(yī)學(xué)雜志Cephalalgia上發(fā)表的研究報(bào)告表明,在68%的試驗(yàn)中,研究對(duì)象稱感到頭痛或不適癥狀加重。而癥狀的輕重程度與試驗(yàn)的順序沒(méi)有關(guān)系。
研究人員并沒(méi)有發(fā)現(xiàn)置身射頻場(chǎng)與所述癥狀的嚴(yán)重程度之間存在明顯的數(shù)據(jù)上的相關(guān),也沒(méi)有發(fā)現(xiàn)射頻場(chǎng)對(duì)心率與血壓的變化有影響。
奧弗泰德爾博士的研究小組得出結(jié)論,對(duì)于研究對(duì)象頭痛和不適癥狀最合理的解釋應(yīng)該是“消極的預(yù)期?!?/font>
(英語(yǔ)點(diǎn)津姍姍編輯)
|