Abstract
Laboratory studies of the biological effects of low-frequency electromagnetic fields (EMFs) have demonstrated that the fields can produce or alter a wide range of phenomena. Explaining the diversity of the reported effects is a central problem. Our basic hypothesis is that the effects are generally indirect, and arise as a consequence of sensory transduction of the fields. In this view, EMF detection and its biological consequences occur in different types of cells. Experimental verification of the hypothesis will ultimately require data showing that the interaction of EMFs with tissue results in biological changes that are the same as or similar to changes that occur during sensory transduction. The goal was to identify the specific phenomena that would be expected to occur if the hypothesis were true. We therefore analyzed the presently accepted models of sensory transduction in the somatic and special senses. Many kinds of processes were identified in connection with transduction of different kinds of stimuli, but we found that a change in the conductance of a membrane ion channel in a neuron or a neuroepithelial cell was the earliest process that occurred in all forms of sensory transduction. Evidence from an appropriate model excitable cell or tissue that EMFs affect membrane currents or membrane potential would therefore support the hypothesis that EMF transduction is a species of sensory transduction.