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Bioelectromagnetism

time. Te purpose of this experiment was to fnd out how human rhythms are afected by the absence

of the sense of time. Te daily rhythms of sleeping and waking were recorded, and cycles that deviated

by 0.8 hours from 24 hours were detected. Tis meant that Sifre’s internal clock, or free-running period,

was 24.8 hours in the cave, cut of from the outside world. Afer this pilot study, the research studies on

human circadian rhythms were performed in artifcial isolation facilities.

Various periodicities in biological processes are coupled, to a certain extent, to geophysical cycles.

Animals have 23–25 hours periods, and plants have 23–28 hours periods. However, the period lengths

and phases of these internally generated (endogenous) daily rhythms of biological organisms are read­

ily controlled by external environmental factors, such as the 24 hours day-night cycle produced by the

earth’s rotation. Biological organisms can adjust their rhythms (Entrainment) based on external envi­

ronmental conditions, which are called synchronizing factors (a Zeitgeber): visible light is a very impor­

tant Zeitgeber.

Among the natural conditions that could serve as a Zeitgeber, lightning and other electromagnetic

phenomena are possible synchronizing factors. Human body temperature and activity have 24-hours

periods and are synchronized by external environmental factors. If external environmental stimuli are

removed, the free running cycle rhythm becomes 25.3 hours. During the 1960s, research using under­

ground rooms or caves, to isolate subjects from external information to investigate human circadian

rhythms has been active.

First, the free-running circadian rhythms of activity such sleep and awake, body temperature, urina­

tion, and other rhythms of subjects living in the two rooms were studied. Te subjects were informed

about neither the shielding nor the artifcial feld. In both rooms, volunteer was placed for 1 month with

no information from outside without letters. Tese parameters have usually a 24-hours cycle which

synchronizes with day-night cycle produced by the earth’s rotation (Wever, 1979).

Human circadian rhythms arise endogenously (Aschof and Wever, 1962). Even without time cues

in a constant environment, they deviate only slightly from 24 hours, with most autonomous human

rhythms approximating 25 hours. Typically, oscillators governing diferent physiological parameters

such as activity and rectal temperature are coupled and run synchronously (Wever, 1975) but may run

asynchronously in “internal desynchronization.” Te rhythms of all diferent measured parameters run

synchronously to each other. Tis is internal synchronization which is the case in most experiments. In

about 20% of the experiments, the internal desynchronization occurs as shown in Figure 27 of Wever’s

book (1979, p. 48). It is the examples of internal desynchronization. Subject lives under constant condi­

tions without time cues. Temporal course of the rhythms is shown. Presented are the successive periods,

one beneath the other. Te experiment is divided into two sections (A and B). Te activity rhythm is

represented by bars (black = activity; white = rest). Te rectal temperature rhythm is represented by tri­

angles, maximum temporal position (Δ) and minimum values (˜). Te circadian rhythm of activity was

“split” into two rhythms, with periods of 25.7 and 33.4 hours. Te lengthening of the period for subjects

in the shielded room was statistically signifcant. During frst 14 days, measured variables run synchro­

nously to each other with equal periods of 25.7 hours. Afer that time, the two rhythms ran separately,

which means that internal desynchronization occurred spontaneously. On the 14th subjective day, the

period of the activity rhythm lengthened to a mean of 33.4 hours without any environmental factor

being changed and the period of the rectal temperature rhythm shortened to 25.1 hours. In about 20% of

the experiments, internal desynchronization occurred. Tis phenomenon was not observed for subjects

living in the unshielded room.

As early as the 1960s, studies on the efects of SR electric feld on the circadian rhythm were done. To

investigate the efect of natural electric felds on the circadian rhythm of human activity, Wever con­

ducted an experiment focusing on the efects of 10 Hz electric felds. Te reason why 10 Hz electric feld

is used comes from that the original suggestion of Schumann prediction should be at 10 Hz. To provide

isolation from external sound, light, and other cues, two underground rooms were installed. Two iden­

tical rooms, one shielded and the other unshielded, allowed simultaneous testing of feld-exposed and