How hearing loss differs from vision loss

How hearing loss differs from vision loss

Both hearing loss and vision loss affect us in life-changing ways. But we don’t lose our hearing in the same way we lose our sight – they are profoundly different.

It goes beyond the anatomical differences between ears and eyes. Since one in six of us already experience hearing loss, there’s a further difference that’s worth understanding.

Imagine if your vision was selective

Vision loss is non-selective – if, for example, you can’t make out items that are close to you caused by far-sightedness (hypermyopia) or age-related presbyopia, then your vision is affected equally for everything you see within a given distance.

There are no exceptions: your mug of tea will be just as blurry as your newspaper, assuming they’re about the same distance from your eyes.

Hearing loss, however is often selective. It’s not just about the loudness or quietness of a noise, it’s the type of noise – the frequency – that can influence which sounds you hear. It’s the audio equivalent of looking at a Snellen eye test chart and seeing certain letters clearly but not others, even if they’re on the same line.

Age-related hearing loss, also known as presbycusis, doesn’t only set in when we get close to retirement age. It starts way back in our twenties. On average, people under 25 can hear higher-pitched frequencies than those over 25.

So it’s not just about volume. The type of sound makes a difference. In normal human speech we use 44 different phonemes (sounds) to form letters and words. Some of these phonemes are harder to hear than others, especially for those who suffer from hearing loss.

Higher-pitched ‘f’, ‘th’, ‘ch’, ‘t’ and ‘s’ sounds can be lost against background noise or even other speech sounds; in particular louder and lower-pitched vowel sounds. If you’ve ever felt like you can hear that someone is talking but can’t hear what they are saying, it’s because hearing loss can be selective, affecting certain frequencies while leaving others untouched – even if they’re at the same volume.

‘Yanny’ or ‘laurel’?

The well-known ‘Yanny or Laurel’ internet phenomenon neatly illustrates the split in frequency perception. This low-quality audio recording of the word ‘Laurel’ divided audiences around the world. Some listeners hear ‘laurel’, others hear ‘yanny’.

While the device you’re using to play the infamous recording can make a difference, many commentators, including some audiologists, believe it’s down to the frequency sensitivity of your own ears. The words ‘laurel’ and ‘yanny’ share similar frequencies, so just a small variation in your ears’ frequency sensitivity could make all the difference to the word you hear.

If you’re looking for a similarly mind-bending trick, take a look at this video. While you listen to it, say either ‘green needle’ or ‘brainstorm’ in your head. Like magic, it will influence the sound you hear. When it comes to hearing, the mind is a powerful thing!

How hearing aids help

So far we’ve learnt that hearing loss affects the type of noise as much as it does the volume of noise. So how do hearing aids help if they are just non-selective amplifiers? It’s a great question. In fact, older models of hearing aids were exactly that: non-selective amplifiers. They would amplify every frequency, without discretion.

However, modern hearing aids are much more intelligent. They know the difference between a conversation and the background noise around you. They can distinguish between background hiss and your TV or radio, and they adjust accordingly to give you the best possible soundscape. Gone are the days of the ‘dumb’ hearing aid (although they’re still on sale, so watch out).

What to do if you think you have hearing loss

If you want to know more about hearing aids, or you’re just curious about the health of your hearing, contact us now. Get in touch with your local branch of The Hearing Care Partnership to book a free hearing test – book an appointment online today.