The Quiet Danger of Noise-Canceling Headphones
https://gizmodo.com/the-quiet-danger-of-noise-canceling-headphones-1851407784
Noise-canceling headphones offer a tech bro’s solution to the world of sound. They deem everything in your natural environment as “noise” that can be canceled out, allowing you to purely listen to your devices. The technology is generally considered good for your ears by reducing the overall noise levels you’re exposed to. But even though noise-canceling headphones are good for our hearing, it’s a myth that the technology is entirely good for us.
Online forums are full of people complaining about ear pain, nausea, and headaches from noise-canceling headphones. These forums largely share the same conspiracy theory: that active noise canceling (ANC) is dangerous because it puts harmful pressure on your eardrum. However, that’s not quite right either. According to David McAlpine, the academic director of Macquarie University Hearing, there’s a simpler explanation: not hearing your environment is unnatural.
McAlpine says noise-canceling headphones lower the volume that reaches your ears, which is a good thing for your hearing. Using ANC likely means you don’t have to drown out background noise by listening to music at high volumes. The Centers for Disease Control and Prevention says listening to loud sounds for long periods can lead to hearing impairment.
However, too much noise reduction could be problematic. McAlpine says your brain overcompensates to ANC by turning up its internal gain. He says this creates a “listening loss,” as operating at an increased sensitivity alters your neural pathways. McAlpine wrote a paper in 2011 coining the term “Hidden Hearing Loss,” referring to our brain’s inability to process sound, rather than our ears’ inability to hear it.
“If you have a listening loss, it’s like changing your brain’s encryption,” McAlpine said in an interview. “Even if you can change what you’re hearing, you may not get back to the brain state that you had before. It’s not reversible.”
McAlpine describes what happens when people enter his university’s anechoic chamber, a virtually soundless environment. He says people feel disoriented and describe a pressure in their head and ears. The sensations are remarkably similar to when people use ANC. The common thread is that your body is not made to experience total silence, so people react poorly without background noise. There’s a disconnect between what you’re experiencing and what you’re hearing.
“Intense sound damages your hearing, so there are situations where noise-canceling headphones benefit you,” McAlpine said. “At the same time, background noise—features of the soundscape—are critical to orienting yourself in an environment.”
A 2012 study from McAlpine’s coauthor on “Hidden Hearing Loss” asked 17 subjects to wear earplugs for a week. Eleven participants developed tinnitus, a common medical condition where someone perceives a ringing or buzzing noise with no external source. The study suggests that audio deprivation can affect how your brain processes sound, even if your ears are unharmed. However, the condition disappeared after subjects removed their earplugs, so you shouldn’t worry about your noise-canceling headphones giving you long-term tinnitus.
So while ANC can be good for your ears, it could be altering your brain’s listening ability. The truth is, there’s a tradeoff every time you use ANC. You’re hearing the world at a different sensitivity, what McAlpine calls an “altered gain state.” Spending enough time in this state can make it difficult for your brain to “listen” at normal audio levels.
“I do think that we’ve let the big tech companies co-opt our listening habits, monetize it, and sell it back to us,” said McAlpine. “Their solution to the hearing problem is probably creating a listening problem.”
## Origins of the Myth
There are a couple of myths surrounding noise-canceling headphones. The first is courtesy of Big Tech, which claims that noise-canceling headphones are your solution to the noisy world. As McAlpine says, they’re solving one problem with another, an all too familiar strategy in tech.
The second myth is that ANC is somehow bad for your ears. Wirecutter’s testing found that Apple Airpods and other popular headphones reduced noise by about 10 dBs, which may not be as effective as they claim but is still better than nothing.
ANC works by emitting a sound wave that’s exactly opposite to your environment’s noise. The two waves, from the environment and the headphones, effectively neutralize each other, resulting in that artificial silence you’ve come to love.
However, it’s understandable to believe that because something hurts your ears, it’s bad for your ears. And the myth is rooted in some truth. If you do find ANC painful in any way, the technology could be messing with your brain’s perception of your environment and triggering some kind of instinctual discomfort.
## Why It’s Pervasive
Noise-canceling headphones have become fairly commonplace in our society because the modern world is increasingly noisy. Cars, planes, construction, and electronics contribute to a far noisier world than our ancestors had. Likewise, our hearing problems are getting worse, as our brains and ears struggle to keep up with the changing times.
The issue noise-canceling headphones try to address is a serious one. Noise pollution has been linked to a higher rate of cardiovascular disease, and it’s being increasingly recognized as a harmful pollutant, similar to air and light. Plus, other studies have found that noise-canceling headphones can help improve your focus.