Imagine walking through a centuries-old building. The floors creak. The air feels heavy. Suddenly, your chest tightens. The hair on your neck stands up. You feel watched. A wave of dread washes over you for no reason you can name. To many, this is the unmistakable presence of something supernatural. To scientists, it might just be the sound of a fan.
Not the sound you can hear. Something far lower. Something your ears miss completely but your body registers in ways that feel profoundly, terrifyingly real. This is infrasound—frequencies below the threshold of human hearing, typically under 20 Hz—and it may explain more ghosts than any spirit ever has.
The Study That Should Change Everything
In April 2026, a team of researchers at MacEwan University published a study that adds powerful new evidence to a decades-old hypothesis. Their paper, "Infrasound exposure is linked to aversive responding, negative appraisal, and elevated salivary cortisol in humans," appeared in Frontiers in Behavioral Neuroscience. The research team, led by Kale R. Scatterty and senior author Rodney M. Schmaltz, designed an experiment that cuts straight to the heart of the ghost debate.
Thirty-six participants were exposed to a 2×2 experimental design. Some heard calming music. Others heard unsettling music. For each group, the researchers either played infrasound at approximately 18 Hz or left it off entirely. The participants didn't know when the infrasound was playing. They couldn't see the equipment. They simply sat, listened, and reported how they felt.
The results were striking—and not in the way believers might hope.
First, the participants could not detect the infrasound. Their ability to guess whether it was playing was no better than chance (p = 0.241). They didn't feel vibrations. They didn't hear rumbling. The sound was, to their conscious minds, just not there.
Yet their bodies knew something was wrong. Salivary cortisol, a hormone associated with stress, rose significantly in participants exposed to infrasound (p = 0.022). They reported increased irritability, disinterest, and sadness. The music's emotional tone—calming or unsettling—didn't matter. The infrasound produced these effects regardless.
Most importantly, there were no expectancy effects. Participants who suspected they were in a study about ghosts or haunting didn't react differently than those who had no idea. The physiological response was automatic, unconscious, and entirely independent of belief.
Rodney Schmaltz, the senior author, has built his career studying pseudoscience and misinformation. He knows exactly how these findings will be received. As he put it:
"Consider visiting a supposedly haunted building. Your mood shifts, you feel agitated, but you can't see or hear anything unusual... If you were told the building was haunted, you might attribute that agitation to something supernatural. In reality, you may simply have been exposed to infrasound."
The implications are profound. Every "cold spot," every feeling of being watched, every unexplained dread in a darkened corridor—any of them could be the invisible whisper of infrasound, and the experiencer would never know.
A History of Sound and Spirits
The MacEwan study doesn't exist in a vacuum. It builds on a line of research stretching back nearly three decades, beginning with one of the most colorful papers in skeptical literature.
In 1998, Vic Tandy, a lecturer at Coventry University, published "The Ghost in the Machine" in the Journal of the Society for Psychical Research. Tandy wasn't investigating ghosts. He was working in a lab that happened to feel haunted. Workers reported feelings of depression, anxiety, and occasional glimpses of a gray figure at the edge of vision. Tandy, an engineer by training, noticed that his fencing foil—left clamped in a vise—vibrated inexplicably in certain parts of the room.
He traced the cause to a newly installed extractor fan producing a standing wave at 18.98 Hz. When the fan was switched off, the "haunting" stopped. Tandy went on to investigate a supposedly haunted cellar in Coventry in 2001 and Warwick Castle in 2004, finding similar infrasonic frequencies at both locations.
Tandy's work captured the public imagination, but science demands replication. In 2003, the Infrasonic Concert at London's Purcell Room took the idea further. Composer Sarah Angliss, working with scientists, embedded infrasound into a live musical performance. Audience members didn't know when it was playing. The result? Approximately 22% of attendees reported strange sensations—chills, anxiety, unease—when infrasound was present.
But science is messy, and not all experiments succeed. In 2009, Chris French and his colleagues published the "Haunt" Project, a large-scale attempt to replicate the infrasound-paranormal link. They exposed participants to infrasound in a specially designed chamber and found... nothing. No increase in anomalous experiences. No correlation between infrasound and ghostly sensations. The effect, it seemed, was more elusive than earlier studies suggested.
The MacEwan study helps us figure this out. By focusing on physiological stress responses rather than subjective ghost reports (as previous experiments did), they found a robust effect that doesn't depend on participants interpreting their sensations as anything paranormal. The "Haunt" Project may have failed to confirm the earlier results, but the MacEwan team found something more fundamental: infrasound stresses the human body in ways that can be misinterpreted as supernatural, especially in contexts primed for such interpretations.
The Paranormal Community's Reaction: Dismiss, Deflect, Rationalize
Here is where the story becomes less about physics and more about psychology. Because the paranormal community has not greeted this research with curiosity; it has greeted it with the full arsenal of motivated reasoning.
The reactions fall into several predictable categories, each revealing more about belief preservation than about infrasound.
Category One: Partial Acceptance, Strategic Retreat
Some paranormal investigators acknowledge that infrasound might explain certain sensations—feelings of unease, cold spots, a sense of presence—but they quickly deploy the "not everything" defense. Infrasound doesn't explain Electronic Voice Phenomena (EVPs), moving objects, physical contact, or full-bodied apparitions. Therefore, they argue, infrasound is just one factor among many, and the paranormal remains untouched.
This sounds reasonable until you examine it closely. It's the logical equivalent of saying, "Gravity doesn't explain why this apple is red; therefore gravity isn't real." Infrasound was never proposed as a universal theory of all paranormal claims. It explains a specific category of experiences—sensations of presence, dread, and unease—that form the bedrock of most ghostly encounters. Removing that foundation doesn't collapse the entire edifice of belief, but it should make investigators more cautious about what they consider evidence.
Category Two: The Reversal
A more creative response flips the causal arrow entirely. Some paranormal enthusiasts suggest that infrasound isn't a cause of ghostly experiences but an effect—that spirits themselves generate infrasound. This is unfalsifiable: any scientific finding that threatens to explain the paranormal is simply added into the paranormal framework. Infrasound becomes proof of ghosts, not an alternative to them.
This is the intellectual Möbius strip: no matter which direction evidence points, it always gives the green checkmark to "belief confirmed."
Category Three: Equipment Misrepresentation
Perhaps the most telling reaction comes from the world of ghost hunting entertainment. On Reddit's r/GhostAdventures, users have debunked equipment used on the show, including a device wielded by investigator Jay Wasley that was claimed to use infrasound to "trigger paranormal activity." The device, it turns out, was producing audible tones at 60 Hz—not infrasound (< 20 Hz) at all. The "scientific" equipment was theater, and poor theater at that.
This matters because ghost hunting shows present themselves as conducting scientific investigations. They use technical language, display readings on screens, and speak with authority about frequencies and energies. When that equipment is revealed to be misrepresented or misunderstood, it undermines the entire project's credibility. You cannot claim to be gathering scientific evidence while using devices you don't understand to measure phenomena you haven't defined.
Category Four: Institutional Skepticism from Within
Even the Society for Psychical Research (SPR), an organization dedicated to "studying paranormal phenomena," has been cautious about overstating the infrasound hypothesis. Their Psi Encyclopedia entry on infrasound notes that "experimental weaknesses and exaggerated public claims have left its explanatory power far less secure than often assumed."
This is significant. The SPR is not a debunking organization. It was founded by scientists who believed paranormal claims deserved serious investigation. When even they warn against overstating infrasound's role, it suggests that the popular narrative—enthusiastically promoted by some skeptics—has outpaced the evidence. The MacEwan study helps correct that balance, providing the rigorous experimental design that earlier work sometimes lacked.
Category Five: Media Amplification
Not all paranormal media rejects the science outright. Coast to Coast AM, the long-running late-night paranormal radio program, covered the MacEwan study. Coverage on such platforms typically frames the research as intriguing but ultimately inconclusive—another piece of a puzzle that, believers assume, will eventually reveal the reality of the paranormal. The science is acknowledged, then gently placed on a shelf labeled "Interesting But Not Conclusive."
Why Science Can't Compete with Belief
The MacEwan study provides something the paranormal community claims to want: rigorous, controlled, peer-reviewed evidence about a phenomenon associated with ghostly experiences. And yet the response is not curiosity but containment. The findings are quarantined, minimized, or reversed so that belief can remain intact.
This is not unique to paranormal investigation. It is a feature of human cognition. When deeply held beliefs encounter contradictory evidence, the mind deploys a sophisticated defense system:
- Discounting: The evidence is flawed, limited, or doesn't apply to the real cases.
- Compartmentalization: The evidence is true but only explains a small subset of experiences.
- Reversal: The evidence actually supports the belief, just in a way scientists "don't yet understand."
- Attacking the messenger: The researchers are biased, closed-minded, or part of a materialist conspiracy.
What makes the infrasound research particularly threatening is that it attacks the experiential core of haunting. Most people who believe they've encountered a ghost didn't see a floating figure or hear a disembodied voice. They felt something. A presence. A dread. A certainty that they were not alone. These feelings are the raw material from which ghost narratives are constructed. Infrasound explains the raw material. It doesn't require believers to be dishonest or foolish—only human, with human nervous systems that evolved to detect threats in environments where low-frequency vibrations often meant danger.
The difference between "feeling uneasy" and "seeing a ghost" is narrative, not experiential. Give someone a feeling of dread in a neutral context, and they might call it indigestion. Give them the same feeling in a building labeled "haunted," and they may call it a spirit. The sensation is real. The interpretation is constructed. Infrasound operates on the sensation, leaving the interpretation free to follow cultural scripts.
As Schmaltz's research emphasizes, the physiological response to infrasound is automatic and unconscious. You cannot think or "will" your way out of it. Your body responds before your mind has anything to say. This is why simply telling someone "it's just infrasound" rarely changes their mind. The experience felt real. It was real, as a physiological event. What it meant—ghost or fan—is a separate question that evidence can address, but only if the experiencer is willing to ask.
What This Tells Us About Paranormal Investigation
The field of paranormal investigation presents itself as a scientific enterprise. Investigators use equipment, document findings, and speak of evidence. But the response to infrasound research reveals a fundamental asymmetry. Science changes its mind when the evidence changes. Paranormal investigation, as practiced by most enthusiasts, does not.
A scientific field that encountered a robust, replicated finding explaining a significant subset of its core phenomena would treat that finding as a breakthrough. It would revise its methods, update its protocols, and train its practitioners to control for the newly identified variable. Paranormal investigation, by and large, has not done this. Infrasound is acknowledged in passing, then ignored in practice. Ghost hunters do not routinely measure infrasound at investigation sites and exclude locations where it is present. They do not control for it in their experiments. They do not treat it as a confounding variable to be eliminated.
Instead, they continue to enter darkened buildings with spooky histories, armed with equipment of questionable validity, primed to interpret any sensation as potentially supernatural, in environments where infrasound may be creating exactly the sensations they seek to document. It is less investigation than confirmation theatre.
The MacEwan study doesn't close the book on ghosts. No single study could. What it does is demonstrate, with rigorous methodology and physiological measurement, that a significant component of the ghostly experience has a mundane explanation that doesn't require spirits, energies, or other dimensions. The honest investigator should find this liberating. It means that some percentage of "unexplained" experiences can be explained, freeing attention for whatever remains genuinely puzzling.
But honesty requires something that belief preservation does not: the willingness to be wrong.
The sound of silence is not the absence of noise. It is the presence of frequencies we cannot hear, shaping our moods, our fears, our certainties. It is the hum of a fan in a Coventry laboratory, the vibration of old plumbing in a Edinburgh cellar, the low rumble of traffic through ancient walls. It is real. It is measurable. It is, in perhaps many cases, the "ghost."
The only question is whether believers will listen.
Sources
Fact Checked on April 29, 2026 - Edited on April 29, 2026