Introduction
The nervous system consists of the peripheral nerves, the spinal cord, and the brain. It is
the means by which the organism receives information from the environment, and by
which it controls its internal processes. With the exception of visual systems which are
generally sensitive to only a small portion of the electromagnetic spectrum, most
animals seem to lack specific receptors for EMFs. Thus, in most cases, EMFs cannot be
consciously perceived unless thay are so intense that they stimulate sensory nerves via
the familiar phenomena of shock or heat. However, not all information gathered by the
senses is processed at the conscious level, and there is no physiological principle that
would preclude the subliminal detection of EMFs by the nervous system. Indeed,
considering both the rich frequency spectrum of naturally-present EMFs that has existed
throughout the evolutionary period, and its known relationship to geological,
atmospheric, and cosmological phenomena, it would be surprising if the nervous system
were not sensitive to low-level EMFs.
The nervous system is the body's master controller. An EMF effect on it could be
expressed in two ways: an alteration in the properties or function of the nervous system
itself, such as in its electrical, biochemical, or histological characteristics (primary
effect); or an alteration in the body's systems or organs that are controlled by the nervous
system, such as the endocrine or cardiovascular systems (indirect effect). In this chapter
we describe the reports of primary effects on the nervous system- effects involving other
organs and tissues are described in the succeeding three chapters.
Direct Effects
We used the salamander electroencephalogram (EEG) pattern as a means to monitor for
possible direct effects of high-strength magnetic fields applied along a specific axis through the head
(1). The field induced the onset of a slow or delta-wave pattern, and a large fluctuation in activity was
seen as the field was slowly decreased from 1000 gauss to zero (see fig. 2.5). These observations were
confirmed and extended by Kholodov (2) in 1966 in the rabbit EEG. He found that the presence of
delta waves and the number of spindles (brief bursts of 8-12 Hz waves) were both increased by 1-3
minutes' exposure at 200-1000 gauss. In about half the animals tested these reactions lasted at least 30
seconds. In addition to these changes, which occurred after a latent period of the order of 10 seconds,
Kholodov sometimes observed a desynchronization reaction (an abrupt change in the main rhythm) 2-
10 seconds after the field was turned on (in I4% of the cases), or off (24%). He attributed the increase
in spindles and slow waves to a direct action of the magnetic field on the nervous system and the more
rapid, and relatively less frequent, desynchronization reaction to the electric field which was induced in
the tissue as a result of the change in magnetic field during the turn-on turn-off. Chizhenkova (3)
confirmed this hypothesis by exposing rabbits to 300 gauss for either 1 minute or 1.5 seconds. At the
longer exposure period, the changes reported by Kholodov were observed, but following 1.5-second
exposures only the desynchronization reaction occurred. In addition, Chizhenkova showed that a ten-
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