Noise-cancelling headphones: why they're controversial (and what the experts say)

BarcelonaThe health of our hearing is not usually one of our main concerns. In fact, we are not very aware of it socially, and the health system lacks resources and professionals to address the hearing problems of the population. And among young people the situation is especially worrying: it will probably not be until a few years before they notice that exposure to new environments (festivals or concerts with very high volumes) and excessive use of some devices (for example, headphones) can be harmful in the long term.

Recently, a number of audiologists raised concerns about noise-cancelling headphones and their possible consequences on our brain's ability to distinguish sound. According to the BBC, linked some young people who had been diagnosed with auditory processing disorder (APD) to excessive use of these devices. Is it true that these headphones can affect our ability to hear and distinguish the noises around us? There is still a lot of research needed to make such a claim: we spoke to experts to clear the waters.

Noise-cancelling headphones: no need to panic

Going to a crowded bar and not being able to concentrate on the voice of the person speaking to us, not knowing where the sound of the coffee machine is coming from, confusing sounds... In short, hearing well but not being able to understand sounds. This is what could cause an auditory processing disorder. Gerard Encina-Llamas, an engineer and scientist in auditory sciences, explains that APD is diagnosed "when we don't know exactly what's going on": "There is a problem, but we can't measure it with current techniques. We know that it has nothing to do with the cochlea or the cochlea, so the problem comes from the brain, but we don't know why."

Could we suffer from this disorder if we use noise-cancelling headphones for too long? According to Encina, a researcher at the Copenhagen Hearing and Balance Center in Denmark, "there is no scientific evidence" to prove it or anything that could explain hearing loss from using these devices.

However, this does not mean that we can abuse it: "We know that exposure to sound for a long time at moderate levels, even if not very loud, can cause permanent damage to some neurons in the auditory nerve." That is, if we talk about young people who use headphones very continuously, when they reach 50 or 60 years old "they will begin to have hearing loss in greater quantities than the current generation, but not because of the cancellation algorithm, but because of prolonged sound exposure."

How does noise cancellation work?

Noise-cancelling headphones work by emitting a sound that cancels out the noise around us. In other words, "if the sound that comes in has a value of +1, the device applies a sound with a value of -1, and they add up to zero," explains Encina. Therefore, we are not exposed to noise, since it does not reach our auditory system: "It cannot affect us because there is no sound pressure." However, this does not mean that some users do not notice effects that surprise them. Bernat Fuentes, who is 24 years old and has been using these devices for a few months, explains that, however, "he has the feeling that everything is distorted" when they are removed: "Even the ambient sound of silence seems annoying to me," he explains, adding that he notices his senses "altered," although only for a while.

"A serious public health problem"

Experts are concerned about the treatment of hearing problems: "There is a feeling that it is not part of healthcare, or that it is something very peripheral," says Dr. Francesc Roca Ribas, head of the Otorhinolaryngology service at the Germans Trias i Pujol University Hospital. "It is a very serious situation," says the doctor, who is also vice-dean of the degree in general audiology at UVic-UCC, the first in the whole of Spain.

The figures, although they are an approximation because there is still a lack of study, reflect that only 30% of the population that needs hearing aids is on the doorstep. The main reason is economic, but there is also a cultural factor: "We see it as a feeling of decadence." And the lack of professionals also counts: there are no audiologists in Spain. This is the most necessary figure: otorhinolaryngologists are specialists in the ear, but experts in the auditory function are needed. In fact, it will not be until 2027 when the first batch of audiologists will arrive, thanks to the University of Vic.

All this demonstrates "a serious public health problem," says Gerard Encina. Especially because there are a large number of young people who are overexposed to noise, and an increasingly ageing population: "There is a clear relationship between hearing loss and age, and a clear relationship between hearing loss and cognitive problems." And experts also demand aid: Spain is one of the most backward countries in the field of audiology and does not subsidize hearing aids for the population either: "We are mistreating people who have a problem in one of the most important senses," says Encina.