Unilateral hearing loss, or single-sided deafness, is much more widespread than people realize, prominently in children. Age-related hearing loss, which worries most adults at some point, tends to become lateral, in other words, it affects both ears to some point. Because of this, the public sees hearing loss as a binary — somebody has normal hearing in both ears or decreased hearing on both sides, but that ignores one particular kind of hearing loss completely.
A 1998 research estimated approximately 400,000 kids had a unilateral hearing loss due to injury or disease at the time. It’s safe to say that number has gone up in that last two decades.
What is Single-Sided Hearing Loss and What Causes It?
As its name implies, single-sided hearing loss suggests a reduction in hearing only in one ear. The hearing loss can be conductive, sensorineural or mixed. In intense cases, profound deafness is potential.
Causes of unilateral hearing loss vary. It may be caused by trauma, for instance, someone standing next to a gun firing on the left might end up with moderate or profound hearing loss in that ear. A disease can lead to this issue, as well, for example:
- Acoustic neuroma
- Waardenburg syndrome
Whatever the origin, an individual who has unilateral hearing needs to adapt to a different method of processing sound.
Direction of the Sound
The brain uses the ears nearly just like a compass. It identifies the direction of noise based on which ear registers it initially and in the maximum volume. When a person speaks to you while standing on the left, the brain sends a message to flip in that direction.
With the single-sided hearing loss, the noise will only come in one ear no matter what way it comes from. In case you have hearing in the left ear, then your head will turn left to look for the sound even if the person talking is on the right.
Think for a minute what that would be like. The audio would enter 1 side no matter where what direction it comes from. How would you know where a person speaking to you personally is standing? Even if the hearing loss isn’t profound, sound management is catchy.
Focusing on Audio
The brain also uses the ears to filter out background sound. It tells one ear, the one closest to the noise that you want to concentrate on, to listen for a voice. The other ear manages the background noises. That is precisely why in a noisy restaurant, so you may still focus on the conversation at the table.
Without that tool, the mind gets confused. It is not able to filter out background noises like a fan blowing, so that’s all you hear.
The Ability to Multitask
The mind has a lot going on at any given time but having two ears allows it to multitask. That’s why you’re able to sit and examine your social media sites whilst watching Netflix or talking with family. With only one working ear, the mind loses that ability to do something while listening. It has to prioritize between what you see and what you hear, which means you usually lose out on the conversation around you while you browse your newsfeed.
The Head Shadow Impact
The head shadow effect describes how certain sounds are inaccessible to an individual having a unilateral hearing loss. Low tones have extended frequencies so they bend enough to wrap round the head and reach the working ear. High pitches have shorter wavelengths and do not survive the trek.
If you are standing beside a person having a high pitched voice, you may not understand what they say unless you flip so the working ear is facing them. On the flip side, you may hear somebody with a deep voice just fine no matter what side they are on because they produce longer sound waves which make it into either ear.
Individuals with only minor hearing loss in just one ear tend to accommodate. They learn quickly to turn their head a certain way to hear a buddy speak, for instance. For people who struggle with single-sided hearing loss, a hearing aid may be work round that yields their lateral hearing to them.