July 1, 2011
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 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.