The first aim of this study was to compare the possible effects arising from continuous wave radio frequency versus pulse modulation irradiation on human EEG. The second aim was to investigate the usefuleness of non-linear EEG analysis method.
Twelve healthy subjects (six females and six males) in the age of 10 to 32 years participated. They were seated comfortably with eyes closed while resting EEG was monitored.
An increase in alpha wave power as found in a previous study of Huber et.al. (publication 9345) should be replicated in this study.
The study followed a fully counterbalanced cross-over design, but analysis was only single blind due to ELF artefacts present during exposure.
|Exposure duration||intermittent, 3 x 15 min, see add. information|
|Chamber||Sessions took place in a shielded room with the signal generator and amplifier located outside. Physiological recording equipment and a person monitoring it were also present.|
|Setup||The exposure device was a model handset consisting of a metallic casing acting as ground and a monopole antenna. It was placed according to the IEEE standard 'touch' ear to mouth position for exposure of the left hemisphere.|
|Sham exposure||A sham exposure was conducted.|
|Additional info||Participants attended a 2-h recording session in which three 15-min periods (2 x 7.5 min) were randomly assigned to CW, PW, and sham exposure and were each enclosed by 7.5 min of pre- and post-exposure. After each 7.5-min period, there was a 1-min break in which subjects were instructed to open their eyes and stretch.|
No changes to alpha wave power were found for either using linear nor non-linear analysis methods, and thus the results of Huber et al. could not be confirmed.