An audiologist shares the science behind Halloween’s eeriest noises.
By Elissa Kawamoto, Au.D.
Credit: @sabinamusicrich/Unsplash
From creaking doors and howling winds to the sudden shriek of a movie soundtrack, certain sounds seem almost designed to make our skin crawl. But what is it about these eerie noises that trigger such an instant, visceral reaction even when we know we’re perfectly safe? The answer lies deep within the way our brains have evolved to process sound and identify threats.
The Science of Nonlinear Sounds
Many of the noises that make us uneasy share a key trait: They’re what scientists call nonlinear sounds. These are sound waves characterized by extremely high amplitude and sudden, unpredictable changes in frequency or harmony.
In simpler terms, they’re chaotic and jarring, presenting a stark contrast to the steady, more predictable sounds we associate with calm and safety.
Think of a squeaky hinge, a baby’s cry, or the screech of tires. These noises are nonlinear because they break the expected pattern of sound. Our brains instinctively flag this irregularity as a sign that something might be wrong.
Why We’ve Evolved to Fear Them
Our reaction to these sounds isn’t learned—it’s biological. Studies have shown that humans have evolved to recognize abnormal sound patterns as potential danger signals. In fact, the pathway from ear to muscle tensing is remarkably fast.
That sudden jolt of fear you feel when a door slams or an unexpected scream pierces the silence? That’s your brain’s ancient survival mechanism in action, a system designed to help us respond instantly to potential threats.
When we hear these dissonant, high intensity sounds, our bodies release a surge of adrenaline and cortisol, the same hormones associated with the fight or flight response. Our breathing quickens, muscles tense, and heart rate spikes.
Even though we might be watching a scary movie from the comfort of our couch, our brains can’t fully distinguish between real and perceived danger. The physiological response feels just as real.
Filmmakers have long understood this connection between sound and emotion. The suspenseful, repetitive theme from “Jaws” and the shrieking violins in Hitchcock’s “Psycho” are masterclasses in using nonlinear sounds to manipulate audience emotions and responses. These iconic scores amplify discordant harmonies and erratic frequencies, intentionally triggering our primal fear circuits and keeping us on edge.
Our Ears: The First Line of Defense
Hearing plays a vital role in how we detect and respond to danger and our ears can even help us determine which direction a sound is coming from. When hearing is unbalanced between ears, meaning one ear hears better than the other, that natural sense of direction and distance can become distorted, which can affect both awareness and safety.
That’s one of the many reasons why protecting your hearing is so important. According to research, more than 50 million Americans experience some degree of hearing loss equivalent to roughly 1 in 7 people. The incidence of hearing loss increases with age, yet among adults ages 70 and older who could benefit from hearing aids, fewer than 1 in 3 have ever used them.
October isn’t just Halloween season; it’s also National Protect Your Hearing Month, a good reminder to care for the sense that keeps us alert, safe, and connected.
And October is also Audiology Awareness Month! Another good reminder to share that today’s modern hearing aids are designed to restore natural, balanced hearing. Many feature AI-driven sound processing, directional microphones, and Bluetooth connectivity, helping patients tune in to what matters most while staying aware of their surroundings.
So for anyone who loves the spine-tingling thrill of spooky sounds, maintaining good hearing health ensures you can experience every eerie creak, shriek, and whisper in all their chilling glory.
Elissa Kawamoto, Au.D., is an audiologist at HearUSA in Phoenix. She received her doctorate in audiology from Arizona State University. She is dedicated to advancing hearing healthcare and educating patients and their families on the impact of hearing loss on overall health and wellness.
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An audiologist shares the science behind Halloween’s eeriest noises.