10 probands of different sex and with different mobile phone usage from 35 - 75 years were examined. Two different mobile phones placed at two different positions of the head (ear + Cz position), respectively, were used as exposure sources (i.e. 4 measurements per proband) and for sham exposure. "Cz position" is a position term in the EEG and describes the central position on top of the head.
In 60% of the EEG measurements during exposure to one of the mobile phones at the ear and in 90% of the measurements during the exposure at the Cz position, significant changes of the brain waves were detected compared to the sham exposure.
The authors conclude that the acute exposure of the head to mobile phone fields can change the brain activity, but also that further research is necessary.