NO EFFECTS OF PULSED HIGH-FREQUENCY ELECTROMAGNETIC-FIELDS ON HEART-RATE-VARIABILITY DURING HUMAN SLEEP

The influence of pulsed high-frequency electromagnetic fields emitted by digital mobile radio telephones on heart rate during sleep in healt hy humans was investigated. Beside mean RR interval and total variabil ity of RR intervals based on calculation of the standard deviation, he art rate variability was assessed in the frequency domain by spectral power analysis providing information about the balance between the two branches of the autonomic nervous system. For most parameters, signif icant differences between different sleep stages were found. In partic ular, slow-wave sleep was characterized by a low ratio of low- and hig h-frequency components, indicating a predominance of the parasympathet ic over the sympathetic tone. In contrast, during REM sleep the autono mic balance was shifted in favor of the sympathetic activity. For all heart rate parameters, no significant effects were detected under expo sure to the field compared to placebo condition. Thus, under the given experimental conditions, autonomic control of heart rate was not affe cted by weak-pulsed high-frequency electromagnetic fields.