Perceptibility of simulated VLF-sferics.

Sferics are weak, naturally occurring electromagnetic fields related to specific weather conditions. There are some hints that these signals might be responsible for certain complaints that are often described as "weather sensitivity syndrome." The study's purpose was to find out whether humans, when exposed to simulated sferics, can consciously perceive any kind of psychophysiological changes. 63 subjects were trained within a simple learning paradigm to discriminate between phases where simulated sferics were present or absent. They were reinforced for each correct decision out of 80 judgements by means of acoustic signals. A reward of 100 German marks was pledged to the participant who would achieve the best result of the total sample. The total number of correct judgements did not differ from a random run and no learning occurred. Subjects who reported fewer bodily complaints in their recent past had higher scores in the discrimination task.

Atmospheric electromagnetism: individual differences in brain electrical response to simulated sferics.

The living organism is constantly affected by natural electromagnetic influences covering a wide range of frequencies and amplitudes. One of these natural influences is represented by a phenomenon called atmospherics or sferics. Sferics are very weak electromagnetic impulses generated by atmospheric discharges (lightning). With a newly developed simulation system it was possible to reproduce a previously registered sferics signal and present it to 52 subjects while recording the electroencephalogram (EEG). The repeated application of this stimulus for ten minutes evoked a significant decrease in alpha power in parietal and occipital regions compared to the control condition without sferics presentation. Two constitutional factors were revealed as mediators of sferics effectiveness: the general physical condition of the subjects, and their neuroticism. Individuals with many somatic complaints and a high degree of emotional lability did not respond to the sferics stimulation. This absence of a response is interpreted as an adaptational deficit in reaction to variations in atmospheric parameters.