Biological responses upon modulation of carrier waves with certain extremely low frequencies (ELF)
Certain low frequencies induce strong biological responses either on their own or when used to modulate electromagnetic waves. This may be due to resonance.
In 1975, Bawin and Adey discovered the "calcium efflux effect" which consisted of the efflux of calcium ions from chick brains irradiated with 147 MHz modulated within a certain "window of frequencies" having a maximum at 16 Hz. Other biological responses were induced upon modulation of 450 MHz or 2.45 GHz carrier waves with 16 Hz.
An interpretation has been provided by the ion cyclotron hypothesis based on the fact that 16 Hz is the cyclotron resonance frequency of potassium.
In general, biological responses upon ELF and ELF-modulated fields may be interpreted based on ion resonance frequencies.