How noise cancelling headphones are rewiring your brain… and can lead to hearing PROBLEMS, revealed by top doctors

Sales of noise-cancelling headphones have rocketed in recent years, bringing the ‘perk’ of blocking out all the unwanted sounds around you. 

But last week experts warned that overuse of these popular gadgets could be having an unexpected effect on our hearing – ironically the very thing many people buy them to protect.

Noise-cancelling headphones use clever microphone technology to filter out ambient sounds – with the idea being that this can help you concentrate or listen to music more clearly and at lower volumes.

However, the fear is that people are over-relying on them and this is ‘rewiring’ their brains to forget how to tune out background noise when not wearing them. And this is leading to ‘hearing’ problems.

Indeed, earpods and other headphones that block out ambient sound have been implicated in the rise of young people being referred to NHS audiology services.

Yet when they get there it often turns out their hearing is fine – the problem is actually neurological: their rewired brain is struggling to process and differentiate sounds.

In severe cases, this is known as auditory processing disorder (APD), a condition where it’s difficult to understand sounds – including spoken words – especially in noisy places, such as a classroom, or if people are talking quickly.

An estimated 5 per cent of people aged 18 and younger suffer from APD – in the past the condition was thought to be caused by brain injury or a middle-ear infection. 

But with more children than before presenting with symptoms, according to a recent BBC  report, audiologists are now questioning whether other factors – specifically the rise of noise-cancelling headphones – could be to blame.

Young people may be at particular risk because the ‘more complex, high-level listening skills in your brain only really finish developing towards your late teens’, suggests Claire Benton, vice-president of the British Academy of Audiology.

‘So if you’ve been wearing noise-cancelling headphones in your teens, you’re slightly delaying your ability to process noise.’

A recent pilot study by Hearing Diagnostics, which is developing a new tool to screen for hearing loss, looked at people’s brain sound-processing skills. It found that ‘the over-50s unexpectedly performed better than adults under 30 when you’d expect hearing and processing to get worse with age’, says Ms Benton.

‘In interviews with the under-30s, most were using headphones – often noise-cancelling ones – for several hours every day.’

The researchers, who are planning a larger study, theorised that the younger group’s extensive use of headphones could be negatively impacting their ability to process sounds.

‘Wearing these headphones creates a false environment of only listening to what you want to listen to,’ she explains.

‘Your brain isn’t having to work at it, and we think this might have the same effect as if, for example, you skip “leg day” [when your work-out focuses specifically on the legs] at the gym too often – the muscles in this area begin to shrink and weaken.

‘Likewise, if you’re not strengthening the auditory neural pathways [the nerve routes that carry sound messages from the ear to the brain], they don’t work so well when you do need them.’

Franki Oliver, audiology manager at The Royal National Institute for Deaf People, concurs: ‘It’s important to hear a diversity of sounds so the brain can decide what is important to focus on, and it’s possible that too much artificial filtering of background sounds for hours on end, could eventually make it harder for our brain to differentiate when the headphones come off and normal sound levels resume.’

On top of this, the newer modes that some earphones have, which allow users to boost the volume of just the main speaking voice to an even greater degree, pose an issue as this is the work ‘the brain would normally have done for you’, adds Ms Oliver.

‘In theory, this could make brains slower to react in normal sound situations.’

She says: ‘Noise-cancelling technology is not inherently safer – if the music is played loud there is still a risk to your hearing.

‘But it does offer some protection. The key is to stick to the World Health Organisation’s guidelines of listening with headphones or earbuds for no more than 40 hours per week at 80 decibels or lower.

‘This is usually 60 per cent of your phone’s volume capacity, or a similar noise level to a food blender.’

Claire Benton adds: ‘Noise-cancelling headphones can be useful for people who find noise overwhelming or if they struggle to focus in noisy places.

‘But we need more research to look into exactly what is happening and to study how long is too long when wearing them. Meanwhile, it does seem that moderation is key.’

And we should ‘not underestimate how plastic the brain is’, she adds: even people with auditory processing disorder can ‘improve their ability to hear with the right training, so it seems that these brain pathways can be built up again – reducing headphone use, so a person is hearing the background noise again, will help to some extent’.

Another reason not to ditch those earbud headphones just yet is that noise-cancelling technology is becoming more sophisticated all the time.

‘Recent advances such as the “transparency” setting on newer models allows users to still hear some external noise, which could help maintain the brain’s processing power when it comes to filtering sounds,’ says Franki Oliver.

But while noise-cancelling headphones have their place on your daily commute, experts don’t recommend using them as hearing protection in very loud places, such as at a music concert.

‘We don’t yet know if noise-cancelling technology is good enough to protect your hearing in more extreme situations,’ says Ms Oliver.

‘You’re better off with good old foam earplugs – as long as you push them in properly – so they can block vibrations from getting physically into the ear and damaging the tiny hair cells that sense sound – as once they die off they don’t regrow, leading to hearing loss,’ she explains.

‘If you’re a regular gig-goer, invest in some of the reusable earplugs – such as those made by Loop – which are specially designed to only filter out the more harmful soundwaves of music without cutting you off from the experience and enjoyment.’ 

Note, it’s important for anyone who feels they struggle to hear in any situation to get their ears checked – ask your GP for a referral to hearing services.