Simply, binaural hearing is the ability to hear clearly with both ears.
Why is Binaural Hearing Important?
Humans naturally possess binaural hearing. The same way music nearly always sounds better in stereo rather than mono, hearing is far more useful when your two sound-receivers (ears!) are both in working order.
Particularly important is the fact that binaural hearing provides for 360-degree hearing in a way we often take for granted, allowing us to hear sounds clearly from every direction without turning our heads.
As far as we know, our hearing pinpoints sound in a similar way to that in which GPS satellites pinpoint users, by using the relative time delay between received signals. For example, a sound off at a right angle to the head can reach your nearest ear 0.6 milliseconds before it reaches the ear on the other side. Equally usefully, the sound arriving at each ear can be of slightly different volumes due to what audiologists call ‘head shadow.’
We don’t just hear with our ears, but with our brains too. The ears transmit all this data to the brain, which uses some complicated processes honed over our lifetimes and humanity’s far longer evolutionary career to tell us as best as it can what a sound is and where it’s coming from.
The Benefits of Binaural Hearing
In an evolutionary context, the benefits of being able to hear a sound and immediately pinpoint its location are obvious. Somewhere, far back in the past, enough of your ancestors used their keen binaural hearing to dodge predators that you’re here today to read this article.
Even in the present day, whether we’re on hunting trips, in noisy bars, at concerts, or doing vehicle repairs, we enjoy and rely on intelligibility and localization – the ability to hear a sound clearly and tell where it is coming from – without really even thinking about it.
Binaural hearing also helps us communicate clearly — as sound entering each ear has been demonstrated to stimulate the opposite side of the brain. The precise benefits of this are unclear, but it appears that when we hear with both ears and both halves of the brain we find speech more intelligible and have access to more auditory information, allowing us to better fill in gaps in speech, tune in to specific sound sources and tune out background noise.
What is Binaural Hearing Loss?
Binaural hearing loss is a hearing loss that affects both ears. By contrast, monaural hearing loss affects just one.
Binaural hearing has a wide range of benefits as detailed above, which we often don’t realize until it’s too late. Unfortunately, even mild hearing loss in both ears can have outsized negative effects, as the information the brain receives from the ears becomes hard to process; garbled, confused or just not quite right.
The severity, onset, and specific effects of binaural hearing loss vary from person to person. Some people are quite severely hearing-impaired in both ears, others only mildly. Some people have one ‘bad’ ear and another ‘good’ one. Hearing loss, of course, can arrive suddenly or gradually.
Either way, binaural hearing loss can often result in a marked reduction in our ability to localize sounds, to hear everything that’s going on in our surroundings, and is often accompanied by tinnitus.
Hearing speech clearly is often particularly tricky for those with binaural hearing loss. As referenced above, it’s thought that the interplay between the two halves of the brain after receiving signals from both ears aids both hearing and comprehension. Without this, many hard-of-hearing people (even those with extremely mild hearing loss) have to concentrate hard to clearly hear a single speaker in a noisy room.
Perfectly understandably, this can sometimes lead to tiredness, frustration, and a feeling of exclusion.
Thankfully, whatever the specific profile of your hearing loss, technological advances mean it’s more likely than ever before your hearing can be restored to a passable or even near-perfect level.
Binaural vs Monaural Hearing Aids
The popular idea of a hearing aid is a simple sound amplifier. Until quite recently, this really was the case, and many people still wear this kind of hearing aid. These assistive devices operate on an individual basis, taking the sound that enters the ear and amplifying it.
Why would this present a problem? Isn’t that how the ears work, anyway?
Unfortunately, as detailed above, the ears work by a more opaque and more complicated neurological magic than this. As a result, with individual, one-sided hearing aids, wearers can sometimes hear what’s going on in their surroundings as a plain ‘wall’ of sound while struggling to make out specific sources of noise (like the person in front of them). Plain technology doesn’t always match well to our sophisticated brains.
Nowadays, smarter binaural aids or CROS hearing aids come in a radio-linked pair, creating a convincing imitation of our natural hearing and stimulating our brain’s auditory centers. Tuned right, they can bring back in part or almost in whole our natural powers of localization across a 360-degree range, improve our ability to tune out background noise, and, often, alleviate the symptoms of tinnitus.
Of course, everyone is different and some people will prefer monaural hearing amplifiers instead.
Why Choose Binaural Hearing Aids?
A comparison can be drawn between hearing aids and vision-correcting lenses. After all, with two bad eyes you’d much rather wear a pair of glasses than a monocle, or two monocles together — so why not apply the same logic to your hearing?
Many people take their chances with their two-sided hearing loss, correcting only their ‘bad ear.’ For some people, this is perfectly serviceable, but these individuals are almost certainly missing out on the aforementioned benefits to speech intelligibility, sound localization, and their enjoyment of a full-spectrum soundscape.
Additionally, modern hearing aids have other handy design features that old-style amplifier aids lack. Notably, advances in tiny battery-powered tech allow smart microphones inside the hearing aid to swivel to face and receive sound sources.
Older aids are tuned to mainly pick up sound in the direction in which the wearer is looking, which can sometimes leave a friend struggling to get their attention from behind. A new-model monaural aid can pivot its microphone towards the relevant source of a sound, of course, but this ability is far more useful when it’s two-sided — with the right set of binaural aids, one aid can pivot to listen behind as required while another keeps its attention faced front and center.
Binaural aids can even be fine-tuned for certain environments, sound levels, and personal preference. For example, while it’s a Personal Sound Amplification Product (PSAP,) not a medical-grade hearing aid, the Olive Smart Ear can be set up and tuned for binaural use via a smartphone app.
Binaural hearing aids can be a really useful tool to restore not just your hearing, but the less-noticeable benefits of two-sided hearing most people take for granted.
To find out more, see some useful resources below or check out our other blog articles.
The information in this guide has been written using the following reliable sources: