A recent study reveals that infrasound (very low frequency sounds below 20 Hz) can elevate cortisol levels and increase irritability, providing a scientific rationale for why certain “haunted” locations may evoke feelings of discomfort.
Research by Scatterati et al. has shown that infrasound can evoke irritation and aversion in humans through a combination of self-reports and biological measures, also suggesting a link to increased negative emotional assessments.
Infrasound is defined as sound waves with frequencies below 20 Hz, which can manifest naturally from sources such as tectonic shifts, volcanic eruptions, convective storms, and air-water interactions during upstream water discharge.
Additionally, infrasound is commonly found in urban settings, particularly near ventilation systems, air conditioning units, low-noise piping, traffic, and various mechanical systems.
Exploratory field recordings have detected infrasound energy linked to urban sound environments and live music events.
Professor Rodney Schmaltz from MacEwan University states, “Infrasound is widespread in everyday surroundings, frequently emanating from ventilation apparatus, transit systems, and industrial machinery.”
“Many individuals are unknowingly subjected to these sounds. Our research indicates that even brief exposure can modify mood and elevate cortisol levels. Understanding the effects of infrasound in real-world contexts is crucial.”
The study involved 36 participants who sat alone in a room while either soothing or anxiety-inducing music played.
For half the participants, an inconspicuous subwoofer emitted infrasound at 18 Hz. Afterward, they were asked to report their feelings, emotional evaluations of the music, and whether they suspected infrasound was present. Saliva samples were collected before and after the listening session.
Results showed that cortisol levels in saliva were elevated in participants exposed to infrasound.
These individuals also reported increased irritability, reduced interest, and a perception of the music as sadder, despite not being aware of the infrasound presence.
“This study indicates that the body can react to infrasound even when it goes consciously unheard,” Schmalz explains.
“Participants struggled to accurately identify the presence of infrasound, and their beliefs regarding it had no discernible impact on cortisol levels or mood.”
“When feeling irritable or stressed, cortisol levels naturally rise as a part of the body’s stress response, establishing a connection between increased irritability and elevated cortisol,” notes Dr. Kale Scatterati, a student at the University of Alberta.
“However, exposure to infrasound influenced both outcomes beyond their normal correlation.”
These findings suggest humans can detect infrasound, yet often fail to recognize it, though the underlying mechanism remains unclear.
Furthermore, this research points to the need for further exploration into whether long-term infrasound exposure could affect health due to consistently heightened cortisol levels and mood disturbances associated with increased irritability.
Professor Trevor Hamilton from MacEwan University commented, “Increased cortisol levels trigger alertness and help the body respond to potential stressors.”
“This is an evolutionarily beneficial response but chronic cortisol release can lead to various physiological issues and adversely impact mental health.”
The findings of this research are published in the journal Frontiers in Behavioral Neuroscience.
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Kale R. Scatterati et al. 2026. Exposure to infrasound is associated with aversion, negative evaluation, and elevated salivary cortisol in humans. Frontiers in Behavioral Neuroscience 20; doi: 10.3389/fnbeh.2026.1729876
Source: www.sci.news
