Featured Research

from universities, journals, and other organizations

Electromagnetic fields can disturb learning, study suggests, but only at very high levels

Date:
July 1, 2011
Source:
Ruhr-Universitaet-Bochum
Summary:
The effects of high-frequency electromagnetic fields emitted by mobile phones on humans have been hotly debated for years. In a new study, neuroscientists from Germany have shed light on this question. For the first time, they provide evidence that extremely high-powered electromagnetic fields can influence learning processes on the synaptic level within the brain, independent from other factors such as stress. However, such high levels are not encountered during typical use of mobile phones, the researchers note.

The effects of high-frequency electromagnetic fields emitted by mobile phones on humans have been hotly debated for years. In a new study, neuroscientists from Ruhr-Universitaet-Bochum (RUB) in Germany have shed light on this question. For the first time, they provide evidence that extremely high-powered electromagnetic fields can influence learning processes on the synaptic level within the brain, independent from other factors such as stress. However, such high levels are not encountered during typical use of mobile phones, the researchers note.

"For this effect, very high values are necessary. These do not occur during the daily use of mobile phones," explains Dr. Nora Prochnow, with RUB's Medical Faculty.

Mobile phone derived non-ionizing radiation can produce heat …

High-frequency electromagnetic fields (HEFs) are not only used in mobile phones, but also in a variety of other communication systems like radio, television or cordless telephone sets. Mobile phones of the so-called third generation utilize the UMTS technology (Universal Mobile Communication System) with a frequency of 1200 MHz and a relatively weak operating range (3.8-4.8 V/m). With increasing power, electromagnetic fields (EMFs) are able to elicit local warming of body tissues, being also described as a "thermal effect." Reportedly, mobile phones can cause local warming of the brain by less than 0.1C. The effect on function and structure of the brain during long term use of mobile phones (e.g. > 30 min) remains unexplained until now.

… and might influence cellular activity

Furthermore, findings regarding the non-thermal effects of mobile phone emitted EMFs are unclear and contradictory. These comprise, for instance, an increase in permeability and fluidity of cellular membranes, which can be implicated in changes in ion-channel integration and metabolism, even without a detectable change in temperature. This may impair synaptic learning processes in the brain. Until now, experiments could not sufficiently answer the question of whether these effects are derived from non-thermal HEFs or from stress, as it can be induced by handling of the experimental animal (e.g. placing a rat into an unknown environment).

Stress or non-thermal EMF effect -- Scientists find out for the first time

To investigate this question, a new study was performed by scientists of the Department of Neuroanatomy and Molecular Brain Research (Professor Dr. med. Rolf Dermietzel) in cooperation with the Chair of Electromagnetic Theory of the University of Wuppertal. For the experiment, rats were placed into differently powered non-thermal HEFs in the UMTS operating range. Synaptic learning and memory formation were analysed by electrophysiological methods. Furthermore, all animals were tested for stress hormone release immediately following the HEF exposure.

Mobile phone use seems to be harmless -- critical values for occupational use have to be controlled precisely

The results: Although there was daily training and effortless contact to the exposure environment, increases in blood derived stress hormone levels could be detected for all exposed groups. The stress clearly influences learning and memory formation on the synaptic level in the rat brain. High-powered EMFs (SAR 10 W/kg) also have a significant effect on learning and memory formation. In contrast to this, weak EMFs (SAR 0 and 2 W/kg) lead to no detectable changes or impairments.

"These results cannot directly be transferred to humans," says Nora Prochnow. "But in the animal model, it can be demonstrated that neuronal mechanisms of synaptic learning can serve as a target for high powered EMFs."

However, there is no need for serious concerns: humans are not exposed to such high-powered EMFs during daily mobile phone use. Nevertheless, the matter has to be regarded differently in special occupational situations, for instance during the use of body worn antenna systems as it is common for security services or military purposes. Here, critical levels for occupational exposure may be reached more easily and have to be controlled carefully.


Story Source:

The above story is based on materials provided by Ruhr-Universitaet-Bochum. Note: Materials may be edited for content and length.


Journal Reference:

  1. Nora Prochnow, Tina Gebing, Kerstin Ladage, Dorothee Krause-Finkeldey, Abdessamad El Ouardi, Andreas Bitz, Joachim Streckert, Volkert Hansen, Rolf Dermietzel. Electromagnetic Field Effect or Simply Stress? Effects of UMTS Exposure on Hippocampal Longterm Plasticity in the Context of Procedure Related Hormone Release. PLoS ONE, 2011; 6 (5): e19437 DOI: 10.1371/journal.pone.0019437

Cite This Page:

Ruhr-Universitaet-Bochum. "Electromagnetic fields can disturb learning, study suggests, but only at very high levels." ScienceDaily. ScienceDaily, 1 July 2011. <www.sciencedaily.com/releases/2011/06/110630091657.htm>.
Ruhr-Universitaet-Bochum. (2011, July 1). Electromagnetic fields can disturb learning, study suggests, but only at very high levels. ScienceDaily. Retrieved September 16, 2014 from www.sciencedaily.com/releases/2011/06/110630091657.htm
Ruhr-Universitaet-Bochum. "Electromagnetic fields can disturb learning, study suggests, but only at very high levels." ScienceDaily. www.sciencedaily.com/releases/2011/06/110630091657.htm (accessed September 16, 2014).

Share This



More Mind & Brain News

Tuesday, September 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

FDA Eyes Skin Shocks Used at Mass. School

FDA Eyes Skin Shocks Used at Mass. School

AP (Sep. 15, 2014) The FDA is considering whether to ban devices used by the Judge Rotenberg Educational Center in Canton, Massachusetts, the only place in the country known to use electrical skin shocks as aversive conditioning for aggressive patients. (Sept. 15) Video provided by AP
Powered by NewsLook.com
Shocker: Journalists Are Utterly Addicted To Coffee

Shocker: Journalists Are Utterly Addicted To Coffee

Newsy (Sep. 13, 2014) A U.K. survey found that journalists consumed the most amount of coffee, but that's only the tip of the coffee-related statistics iceberg. Video provided by Newsy
Powered by NewsLook.com
'Magic Mushrooms' Could Help Smokers Quit

'Magic Mushrooms' Could Help Smokers Quit

Newsy (Sep. 11, 2014) In a small study, researchers found that the majority of long-time smokers quit after taking psilocybin pills and undergoing therapy sessions. Video provided by Newsy
Powered by NewsLook.com
'Fat Shaming' Might Actually Cause Weight Gain

'Fat Shaming' Might Actually Cause Weight Gain

Newsy (Sep. 11, 2014) A study for University College London suggests obese people who are discriminated against gain more weight than those who are not. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

      Technology News



      Save/Print:
      Share:

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile: iPhone Android Web
      Follow: Facebook Twitter Google+
      Subscribe: RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins