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Many headache patients believe that weather changes act as pain triggers. Therefore, the present study investigated the psychophysiological influence of an indicator of atmospheric instability, Very Low Frequency (VLF)-sferics, on 32 subjectively weather-sensitive women suffering from migraine attacks and/or tension-type headaches. It was analyzed if sferics exposure is able to induce electrocortical changes as well as headache symptoms. The subjects, who had been divided into two groups, participated in a sferics simulation study. The experimental group (n = 16) underwent a ten-minute exposure to 10kHz-sferics impulses followed by 20 minutes without treatment in order to examine possible prolonged sferics effects. The control group (n = 16) received no treatment. As dependent measures, EEG spectral power was compared between the two groups at six electrode sites (F3/F4; P3/P4; O1/O2). Sferics exposure provoked increases in absolute alpha and beta power during the treatment. The alpha power enhancement was still present at parietal sites at the end of registration (20 minutes after the end of exposure). The stimulation did not induce headache symptoms.

22 believers and 20 skeptics of extrasensory perception (ESP) participated in a telepathy experiment. Subjects were asked to judge the covariation between transmitted symbols and the corresponding feedback given by a receiver. Believers overestimated the number of successful transmissions ('hits'). Skeptics were characterized by accurate hit judgments. For believers, positive correlations between hit-responses, their heart rates, and their experienced arousal were found. In addition, subjective arousal was positively associated with the hit estimates given at the end of the experiment. This response pattern was absent in the group of skeptics. It is concluded that covariation bias as a psychophysiological concept plays an important role in the maintenance of paranormal belief.

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.

The present study investigated psychophysiological responses to paced respiration of different frequencies. Twenty men and 20 women (mean age: 24.3 years) underwent five breathing conditions (paced with 0.15 Hz, 0.20 Hz, 0.25 Hz, 0.30 Hz, and unpaced), each lasting 5 min. As dependent physiological measures heart period, and different heart period variability (HPV) parameters were assessed. Psychological variables consisted of mood estimates as well as rated accuracy and effort to follow the pacing rhythm. HPV decreased with higher breathing frequencies, under paced and unpaced conditions, whereas mood ratings did not change. Subjects indicated more effort and less accuracy in following the pacing signal, the more its frequency differed from their spontaneous breathing frequency. The comparison of a spontaneous breathing condition with a frequency-matched paced condition revealed that pacing per se provoked a reduction in heart period. Because this decrease was not accompanied by changes in any of the HPV frequency components, their validity as measures of autonomic control needs to be questioned.

Very-low-frequency (VLF) atmospherics or sferics are pulse-shaped alternating electric and magnetic fields which originate from atmospheric discharges (lightning). The objective of the study was threefold: (i) to analyse numerous parameters characterizing the sferics activity with regard to their suitability for field studies, (ii) to identify meteorological processes related to the sferics activity and (iii) to investigate the possible association of sferics with pain processes in patients suffering from migraine- and tension-type headaches. Over a period of 6 months (July through December) the sferics activity in the area of Giessen (Germany) was recorded. Three sferics parameters were chosen. The number of sferics impulses per day, the variability of the impulse rate during a day and the variability in comparison to the preceding day were correlated with weather processes (thunderstorm, temperature, vapour pressure, barometric pressure, humidity, wind velocity, warm sector). Significant correlations were obtained during the summer months (July, August) but not during the autumn months (October, November, December). During autumn, however, the sferics activity was correlated with the occurrence of migraine-type headaches (r=0.33, P<0.01) recorded by 37 women who had filled out a headache diary over a period of 6 months (July–December). While the thunderstorm activity was very intense during July and August, no relationship between sferics and migraine was found. In summer, tension-type headaches were associated with meteorological parameters such as temperature (r=0.42, P<0.01) and vapour pressure (r=0.28, P<0.05). Although the sferics activity can explain a small percentage of the variation in migraine occurrence, a direct influence was more likely exerted by visible or otherwise perceptible weather conditions (thunderstorms, humidity, vapour pressure, warm sector, etc.) than by the sferics activity itself.

Sferics are electromagnetic impulses generated by electrical discharges during thunderstorms (lightning). One category is comprised of very low frequency electromagnetic waves, traveling over distances up to a thousand kilometers. Sferics have been shown to affect biological responses such as pain syndromes, reaction times, and power in the alpha band of the EEG. In the present study, in which 100 subjects took part, sferics have been studied in their relation to performance on a forced-choice extrasensory perception (ESP) task and to several secondary variables. The general finding is a negative correlation between ESP performance and sferics activity around the time of the session, most notably 24-48 hours prior to the session. Secondary variables appear to modulate this correlation, as has been found in previous research on sferics: the correlation tended to be stronger for persons who scored lower on Neuroticism and higher on the Openness scale of a Five-Factor Personality Questionnaire.

In a previous study a negative correlation was found between the natural sferics activity and scores on an ESP task. We attempted a replication in three studies with 37, 100, and 68 participants. In these studies ESP scores and the level of sferics activity were not significantly correlated. The result for all combined data is significant but with a quite low effect size. Other trends in the data could not be confirmed.

A previously recorded electromagnetic impulse of natural origin, a 10 kHz-sferic, was simulated and presented to 20 subjects. The magnetic component of the signal with a maximum field amplitude of 50 nT and a duration of 500 microseconds was applied over a duration of 10 minutes with a pulse repetition rate that varied statistically between 7 and 20 Hz. After sferics exposure, an additional 20 minutes without treatment were recorded in order to examine possible prolonged effects of sferics stimulation. The control group (n = 20) received no treatment. As a dependent measure, electrocortical changes throughout the course of the experiment were determined by means of EEG spectral analysis and compared between the two groups. Sferics exposure provoked increases in alpha and beta power. The effect was present during stimulation and continued for 10 minutes after the end of treatment. A longer lasting influence of sferics exposure was displayed by subjects with a high degree in weather sensitivity, somatic complaints, and neuroticism, who continued to stay on an enhanced alpha power level until the end of registration (20 minutes after the end of exposure). With these results a general electrocortical sensitivity towards sferics as well as individual differences in sferics reactivity could be demonstrated.

Many patients with migraine believe weather is a trigger for their headaches. The objective of this study was to determine if very low frequency sferics, pulse-shaped electromagnetic fields originating from atmospheric discharges (lightning), are precipitating factors. The occurrence of sferics impulses is characterized by a daily, as well as an annual, periodicity and is thought to be associated with various pathological processes. The diaries of 37 women suffering from migraine and tension-type headaches were analyzed over a period of 6 months and correlated with daily sferics activity and other weather phenomena in the area of Giessen, Germany. From October through December (autumn), sferics activity was correlated with the occurrence of migraine (r = 0.33, P<.01); however, there was no correlation in July and August (summer), when the thunderstorm activity had been very intense. In summer, tension-type headaches were associated with other weather parameters such as temperature (r = 0.36, P<.01) and vapor pressure (r = 0.27, P<.05).

Although it is known that there are fundamental personality differences in the behavioral responses to emotional stimuli, traits have scarcely been investigated in this context by means of functional imaging studies. To maximize the variance with respect to personality, the authors tested 12 control subjects and 12 subjects who had sadomasochistic experiences with respect to the relationship between J. A. Gray's (1970) personality dimensions, the behavioral approach system (BAS) and the behavioral inhibition system (BIS), and brain activity in regions of interest. The BIS was associated with activity in numerous brain areas in response to fear, disgust, and erotic visual stimuli, whereas few associations could he detected between the BAS and brain activity in response to disgust and erotic stimuli.

fMRI studies have shown that the perception of facial disgust expressions specifically activates the insula. The present fMRI study investigated whether this structure is also involved in the processing of visual stimuli depicting non-mimic disgust elicitors compared to fear-inducing and neutral scenes. Twelve female subjects were scanned while viewing alternating blocks of 40 disgust-inducing, 40 fear-inducing and 40 affectively neutral pictures, shown for 1.5 s each. Afterwards, affective ratings were assessed. The disgust pictures, rated as highly repulsive, induced activation in the insula, the amygdala, the orbitofrontal and occipito-temporal cortex. Since during the fear condition the insula was also involved, our findings do not fit the idea of the insula as a specific disgust processor.

fMRI studies have shown that the perception of facial disgust expressions specifically activates the insula. The present fMRI study investigated whether this structure is also involved in the processing of visual stimuli depicting non-mimic disgust elicitors compared to fear-inducing and neutral scenes. Twelve female subjects were scanned while viewing alternating blocks of 40 disgust-inducing, 40 fear-inducing and 40 affectively neutral pictures, shown for 1.5 s each. Afterwards, affective ratings were assessed. The disgust pictures, rated as highly repulsive, induced activation in the insula, the amygdala, the orbitofrontal and occipito-temporal cortex. Since during the fear condition the insula was also involved, our findings do not fit the idea of the insula as a specific disgust processor.

Many neurophysiological studies give evidence for a matching system between action observation and imitation. We used functional MRI to investigate the effects of different instructions for observing identical stimuli of whole-body gymnastics movements. The imitative-like observation mode asked normal human participants to observe the sequence containing repetitive parts and to subsequently imagine the observed movements in the first-person perspective. The evaluative observation mode asked the participants to carefully observe and judge movement accuracy and consistency in the repetitive sequence. We hypothesized that the supplementary motor area would be specifically involved in performing the observational tasks. Results indicate that the SMA proper is generally activated during observation of whole-body gymnastic movements and shows pronounced activation in imitative-like observation mode. Pre-SMA activity can be differentially modulated by instructions related to the observation task.