October 2, 2014
Barely perceptible low-frequency signals nevertheless activate measurable responses in our auditory circuits. Neurobiologists have now characterized the remarkable impact of low-frequency sounds on the inner ear.
Sources of low-frequency signals are a prominent feature of technologically advanced societies like our own. Wind turbines, air-conditioning systems and heat pumps, for instance, can generate such sounds. Hearing thresholds in this region of the acoustic spectrum vary from one person to the next. "But the assumption that the ear is unresponsive to low-frequency sounds because these are seldom consciously perceived is actually quite false. The ear indeed reacts to very low-frequency signals," says one investigator.