Is There a Connection Between Electrosensitivity and Electrosensibility? A Replication Study.

BACKGROUND: Among people with idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF), a better than random detection ability for a 50-Hz 0.5-mT magnetic field (MF) and a propensity to experience more symptoms than controls was reported in a previous study. PURPOSE: The current study aimed to replicate and clarify these results using a modified experimental design. METHOD: Participants of the provocation experiment were 49 individuals with self-reported IEI-EMF and 57 controls. They completed the questionnaires (symptom expectations, Somatosensory Amplification Scale--SSAS, radiation subscale of the Modern Health Worries Scale--MHWS Radiation) and attempted to detect the presence of the MF directed to their right arm in 20 subsequent 1-min sessions. Symptom reports were registered after each session. RESULTS: Individuals with IEI-EMF as opposed to the control group showed a higher than random detection performance (d' index of signal detection theory), while no difference in their bias (ß index) toward the presence of the MF was found. Predictors of reported symptoms were self-reported IEI-EMF and believed as opposed to actual presence of the MF. People with IEI-EMF reported significantly more symptoms particularly in the believed presence of the MF. IEI-EMF was closely related to MHWS Radiation and SSAS scores. CONCLUSION: People with IEI-EMF might be able to detect the presence of the MF to a small extent; however, their symptom reports are connected to perceived exposure.

Idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF) and electrosensibility (ES) - are they connected?

INTRODUCTION: The tendency of experiencing unpleasant symptoms in the proximity of working electric devices is called idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF). Evidence about psychophysiological backgrounds of the phenomenon (i.e., detection ability and mechanisms of symptom generation) is not yet conclusive. METHODS: Participants of the provocation experiment were 29 individuals with self-reported IEI-EMF and 42 control persons. Participants completed questionnaires (symptom expectations, somatosensory amplification - SSAS, modern health worries radiation subscale - MHW-R), and attempted to detect the presence of 50 Hz 0.5 mT magnetic field (MF) directed to their right arm in 20 subsequent 1-min sessions. Heart rate was also recorded and various indices of heart rate variability (HF, LF/HF, SDNN) were calculated. RESULTS: Using the methodology of the signal detection theory, individuals with IEI-EMF as opposed to the control group showed a higher than random detection performance (d' differed slightly but statistically significantly from zero), and they used a significantly lower criterion (ß value) when deciding about the presence of the MF. Detection sessions followed by correct decisions (hits or correct rejections) were characterized by higher HRV (SDNN and HF indices) than periods followed by errors (misses or false alarms). Previous expectations and affiliation to the IEI-EMF group were significant predictors of symptoms reported following exposure. IEI-EMF was closely related to MHW-R and SSAS scores. CONCLUSION: Detection of MF might be possible for people with IEI-EMF to some extent. Although heightened sensibility to MFs may play a role in the development and/or in the perpetuance of the IEI-EMF phenomenon, symptoms attributed to the MF seem to be mainly of psychogenic origin.