Unilateral hearing loss or single-sided deafness, is known as hearing loss in one ear, depending how severe the hearing loss is.

How does the loss in one ear affect your hearing?

The brain uses both ears to pinpoint the location of a sound, to improve our hearing quality and range. This is known as binaural hearing. It can present unique challenges when you lose hearing in one ear.

You can’t always pinpoint where the sound is coming from:

Your brain knows where the sound is coming from by which ear receives the sound first. This is known as localization or directional hearing. When a person only has one ear to hear from he or she may have difficulty figuring out where the sound originated.

You may struggle to hear in noisy environments:

The brain is in charge of selective hearing, meaning, it filters out noises that aren’t useful. This is harder to do without the aid of a second ear. In a noisy environment, the person with single-sided deafness struggles to hear a single person’s voice.

You may find it harder to tell how loud the sound is:

Your brain “hears” the sound more loudly when it’s heard through both ears than if the same sound were only heard through one ear. The brain receives signals from the nerves located in both ears and uses this information to process the sounds.

You may struggle to multi-task:

Single-sided deafness puts a heavier load on the brain. The more noise the longer it takes your brain to focus on your tasks at hand. If you are listening to someone speak, you may miss a significant amount of what is being said.

Single-Sided Deafness and the “Head Shadow” Effect

The “head shadow” effect is when high-frequency sounds don’t bend around the side of the functional ear, so the person never hears them. The head keeps sounds from the poorer hearing ear from reaching the better hearing ear. That will result in muffled sounds because a person will not be able to hear high-frequency sounds like “s” or “f”.

Treatment Options for Single-Sided Deafness

People with mild to moderate hearing loss may just need a hearing aid. A hearing aid will amplify the sounds that you are not hearing.

Severe to profound single-sided deafness is usually permanent, but sometimes treatable with aids worn on your functioning ear. An audiologist will perform a hearing test, ask you questions to try and identify the reason for your hearing loss. The person with the single-sided deafness may require Contralateral routing of sound, or a Cros hearing aid system, or Bicros hearing aids.