Low-Frequency Noise May Fuel Haunted-House Sensations, Study Finds

A Frontiers in Behavioral Neuroscience study shows that infrasound in the 17–19 Hz range can raise salivary cortisol and increase irritability, making people feel unsettled even when they can’t consciously hear the sound. Environmental sources such as pipes, HVAC, or wind turbines could contribute to alleged hauntings, but infrasound is unlikely to be the sole cause; it may be one piece of a larger combination of factors and expectations, with larger studies needed.