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  PIERS Online Vol. 3 No. 5 2007 pp: 751-758

Behavioral and Cognitive Effects of MW Electromagnetic Field Exposures

Sheila A. Johnston

doi:10.2529/PIERS060907150019

[PDF Full Text (112 KB)]
Downloads: 981

Abstract:

Published studies of MW exposure thresholds for human adverse perception and cognitive effects with an emphasis on replicated results and the weight of scientific evidence, form the scientific basis for IEEE and ICNIRP exposure limits. Established adverse MW effects are associated with whole body heating at levels that usually increase temperature by approximately 1oC or more. In human cognitive studies with low-level MW exposures, high quality replication studies appear to have eliminated many of the ``false positives". Although human cognitive research continues there are no established human cognitive effects at or below standard or guideline limits. In animal spatial memory studies the weight of evidence from six independent research groups is that there is no effect on spatial learning at whole body or local (head) MW exposures within guideline limits and also well above the limits, when whole body temperature did not measurably rise. These replications are of particular note because of the existing large body of scientific evidence of the neurophysiological and neuroanatomical nature of and homology of spatial memory in animals and man. But confirmatory MW exposure, spatial memory experiments in humans are required for health risk assessment. Controversy has followed reports that low level MW exposure caused toxic leakage through the blood brain barrier [BBB] that could lead to cognitive impairment. The BBB area of research remains open while we await the publication of further BBB attempted replication studies. Since changes in temperature are the biologically relevant information, experimental and numerical dosimetry is underway to predict more precisely MW thermophysiological dose-effects on human or animal nervous functions.

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