India, April 28 -- Researchers suggested in the Frontiers in Behavioral Neuroscience journal that infrasound, low-frequency sound waves below the range of human hearing, may help explain why certain places feel unusually eerie or unsettling.
"Consider visiting a supposedly haunted building. Your mood shifts, you feel agitated, but you can't see or hear anything unusual," study co-author Rodney Schmaltz, a psychologist at Canada's MacEwan University, said in a statement. "In an old building, there is a good chance that infrasound is present, particularly in basements where aging pipes and ventilation systems produce low-frequency vibrations."
To explore how unconscious sound influences emotions, researchers asked 36 volunteers to sit alone...