study on brain function
Previous items in "What's New" (May and July, 2000) have
discussed studies by Finnish researchers on RF exposure and brain
function. This group has published another study that suggests that
RF fields affected performance of memory tasks. As with previous
studies, the RF fields appeared to facilitate rather than disrupt
performance. The effects were small and the authors state that the
effect "probably has no practical implications for performance
in daily life". The physiological
mechanism is still not understood. For more details, see "Research
- Clinical - cognitive function".
Koivisto M, Krause CM, Revonsuo A, Laine M, Hamalainen H. The effects
of electromagnetic field emitted by GSM phones on working memory.
another study on EEGs
A number of studies have been reported on RF exposure
and EEGs, with inconsistent
results. Hietanen and colleagues have reported a further study.
Their results suggest that exposure to RF fields emitted by cellular
phones has no abnormal effects on human EEG activity. For more details,
see "Research - Clinical -EEG".
Hietanen M, Kovala T, Hamalainen A-M. Human brain activity during
exposure to radiofrequency fields emitted by cellular phones. Scand
J Work Environ Health 2000;26:87-92.
of scalp nerve abnormality with prolonged use of a cell phone
Dr. Bruce Hocking of Australia has previously suggested that some
cellular phone users can develop symptoms on the side of the head
where they use their phone. He now reports a case of a 72-year-old
man who, after two mobile phone calls of nearly an hour each on
consecutive days, had persistent symptoms like "a bruised feeling"
on his scalp, adjacent to the site where the cell phone was located.
Tests of the nerves that supply sensation to the skin of the affected
areas showed disturbances of the threshold for perception of sensation.
The authors suggest that these findings are not due to thermal mechanisms,
since the blood supply to the scalp is good and since the patient
had no previous trouble despite exposure to many Australian summers.
should be emphasised that this report is based on a single case.
An assumption of a causative association would require, amongst
other things, confirmation of the findings in other individuals.
Hocking B, Westerman R. Neurological abnormalities associated with
mobile phone use. Occup Med 2000;50:366-368.