To investigate the potential effects of 20 min irradiation from an UMTS-mobile phone on event related potentials evoked by standard and target tones in an auditory oddball paradigm.
In two seperate sessions, 29 healthy students were exposed and sham-exposed between two recording blocks of an oddball paradigm. Before and after exposure participants were presented with a random series of 50 ms tone burst at a mean repetition rate of 1500 ms. The subjects task was to count the appearance of targets (=deviant tone burst).
|Exposure duration||continuous for 20 min|
|Repetition frequency||1,500 Hz|
|Setup||mobile phone connected to an external patch antenna which was mounted on a plastic head set; as for applicator a 0.5 mm thick single sided round dual band patch antenna with a diameter of 31 mm was used|
|Sham exposure||A sham exposure was conducted.|
The analysis of the percentage score of correctly counted target stimuli and the auditory thresholds before and after exposure and sham exposure indicated no effect of electromagnetic fields on task performance. Standard stimuli evoked the N100, N200 and P200 component and targets evoked the P300 response. No significant effects of electromagnetic field exposure on the amplitude and latency of the event related potential components were found. Target stimuli evoked stronger gamma wave-frequency band response than standards, however no effect of electromagnetic fields on the magnitude of gamma wave acitivity was found.