A study published in Frontiers in Behavioral Neuroscience has found that exposure to infrasound—sound waves below the human hearing threshold—can elevate stress hormone levels and induce negative mood changes in participants.
Methodology and Key Findings
Researchers exposed 36 participants to 18 Hz infrasound through hidden subwoofers while they listened to either calming or unsettling music. Control participants listened to the same music without infrasound exposure. The volunteers were unable to consciously detect whether infrasound was present during the experiment.
Measurable results from the study indicate:
- Cortisol Levels: Salivary cortisol levels were higher in participants exposed to infrasound compared to those who were not, regardless of the type of music played.
- Mood Changes: Participants exposed to infrasound reported feeling more irritable, less interested, and rated the music they listened to as sadder.
- Awareness: Volunteers could not correctly identify whether they had been exposed to infrasound.
"The body may sense an environmental threat it cannot locate, which could lead to misattribution in settings such as old buildings."
Context and Expert Commentary
Infrasound (frequencies below 20 Hz) is produced by natural and man-made sources, including old pipes, boilers, and ventilation systems in basements.
Prof. Rodney Schmaltz (MacEwan University) stated that the bodily discomfort induced by infrasound may be attributed to paranormal explanations in certain contexts. Chris French (emeritus professor of psychology) noted that research on infrasound has produced mixed results, adding that linking infrasound directly to poltergeist activity may be an overextension of the findings.
The study's authors, led by Kale R. Scatterty, suggest that the body may sense an environmental threat it cannot locate, which could lead to misattribution in settings such as old buildings. They caution that prolonged cortisol elevation can be harmful but state that the long-term health effects of infrasound exposure require further investigation.
Source
The study, "Infrasound exposure is linked to aversive responding, negative appraisal, and elevated salivary cortisol in humans," was conducted by Kale R. Scatterty et al. and published in Frontiers in Behavioral Neuroscience (2026, Volume 20).