R, Graf T, Cote KA, Wittman L, et al.
The authors conducted experiments on 16 healthy young men, who had been
sleep-deprived during the night preceding the experiment. The subjects
were exposed to EMF for 30 minutes prior to a 3-hour sleep episode that
was scheduled in the late morning. The EMF exposure
was 900 MHz, with a spatial peak SAR of 1 W/kg. The experiment consisted
of 3 sessions separated by 1-week intervals. The exposure was to the right
hemisphere or the left hemisphere or was sham, and was randomised and
double blind. There was no effect on sleep stages or sleep onset latency,
but the power density in the 9.75-13.25 Hz range was enhanced during the
initial non-REM part of sleep.
Even though the exposure was on one side of the head, both brain hemispheres
were affected. This is the first study to show that EMF exposure during
waking affects the EEG during
subsequent sleep. The authors postulate that the changes being seen in
both hemispheres suggest that structures like the thalamus could be involved.
They emphasise that conclusions about possible adverse effects on human
health are premature because the underlying mechanisms are unknown.