Overview
- Canadian psychologists tested 36 volunteers as they listened to calming or creepy music with hidden 18 hertz infrasound added by subwoofers.
- Those exposed reported more irritability and lower interest, rated the music as sadder, and showed higher salivary cortisol despite not noticing the sound.
- Infrasound sits below human hearing but is common near ventilation, aging pipes, boilers, heavy traffic, and some natural events.
- The authors call the findings preliminary because the lab exposure was brief and the sample was small, and they want larger studies across more frequencies and real settings.
- Researchers say identifying and reducing chronic infrasound could matter for mental health, since long-term cortisol elevation can harm the body.