Harmonic Analysis of Electrical Activity in Pelvic and Lumbar Regions of Healthy Men.

To noninvasively assess activity of autonomic nervous system (ANS) in pelvic as well as in left and right dorsal lumbar regions of healthy men (n = 26) in the neighborhood of prostate and kidneys, respectively, the study measured the voltaic (voltage differences) and ohmic (electrical impedances) signals. The recorded signals were processed with Fourier transform yielding the ohmic and voltaic spectral peaks in the ranges of Mayer frequency (M = 0.03-0.2 Hz) and in the Traube-Hering frequency of controlled respiration rate (TH = 0.35 Hz), which reflected activity of sympathetic and parasympathetic ANS branches, respectively. The study harvested the median and quartile values of the magnitudes of voltaic and ohmic spectral peaks at M and TH frequencies viewed as the reference values for noninvasive assessment of ANS activity in the regions of prostate and kidneys.