RF stimulation of the Brain at UZH

There is increasing evidence that pulse-modulated radio frequency electromagnetic fields (RF EMF), such as emitted by mobile phones, can alter brain physiology even at intensities below the current exposure limits. The reported effects include changes in electrical activity (EEG, ERP), regional cerebral blood flow (rCBF), intracortical excitability and cognitive function. However, conclusions about possible adverse effects on human health are premature as the underlying mechanisms of these non-thermal effects are unknown.

The electromagnetic spectrum can be divided according to the photon energy or equivalently according to wavelength (λ) or frequency (f). The spectrum has two important divisions: non-ionizing radiation (radiation that does not carry enough energy per quantum to ionize atoms or molecules) and ionizing radiation (radiation that has the potential to ionize an atom or molecule through atomic interactions). It ranges from extremely low frequencies (e.g. power lines), radio frequency and microwave radiation, to infrared, ultraviolet and x-ray radiation. Mobile phone technology facilitates frequencies between 400 MHz - 2.3 GHz.