Two leaves representing bilateral hearing loss

Unilateral Hearing Loss Vs. Bilateral Hearing Loss

Audiology and ENT Clinics, Audiometry, Family Practice and Pediatricians, Hearing Health, Hearing Services

Have you ever wondered why some people don’t seem to be listening, or why others require the television to be just a little bit louder? Have you ever noticed a friend or family member who seems uncomfortable in noisy social settings, or a child who has trouble concentrating? The reason for these actions may surprise you.

Hearing loss is more common than you may think (6-8% of the global population suffers from disabling hearing loss) and can be a challenging obstacle to overcome. The truth of the matter is, many don’t even realize that their hearing ability is having an impact on their lives. And it will affect individuals differently, depending on their age, experiences, and even genetics.

Hearing loss can be categorized as unilateral or bilateral – meaning in one ear or in both. Furthermore, hearing levels can be different or similar between the ears – known as asymmetrical or symmetrical hearing. Unique in their own specific ways, all have the ability to have varying impacts from person to person.

What is Unilateral Hearing Loss?

How many times have you heard, “I can’t hear what you’re saying, come around to my good side”. Do people really have a good side and a bad side in terms of hearing? For some, the answer is a yes. When hearing is within normal limits in one ear but the other ear is affected, the term used to describe this is unilateral hearing loss, but can also be referred to as “one-sided hearing loss”.

Unilateral hearing loss can present as either a reduced ability or complete inability to hear out of one ear. Many who suffer from this type of hearing impairment have difficulty determining the direction of sound, and can struggle to separate background noise and speech.

What Causes Unilateral Hearing Loss?

There are a number of different factors including:

  • Exposure to loud, impulsive sounds
  • Illness or medical conditions
  • Tumors or head injuries
  • Ototoxic medications
  • Congenital malformations

What is Bilateral Hearing Loss?

Bilateral hearing loss, or, “double-sided hearing loss” means just that – a reduced ability to hear in not one, but both ears. The continuum of hearing loss covers a range of levels – from mild to profound to anacusis (which is complete lack of hearing ability). Double-sided hearing loss impairs both ears, albeit possibly at different levels. Most people have one ear that hears better than the other. When hearing impairment is present and the overall severity is the same in both ears, it is known as symmetrical bilateral hearing loss. When hearing loss levels exist in both ears but at varying degrees, this is referred to as asymmetrical bilateral hearing loss. 

What Causes Bilateral Hearing Loss?

There are a number of possible contributing factors but some of the most common causes of bilateral hearing loss include:

  • Advanced age (1 in 3 over the age of 65 has some hearing loss)
  • Exposure to loud noise
  • Ototoxic medications
  • Genetics
  • Head injuries
  • Severe illness or viral infection

Protect Your Hearing

Although there isn’t very much that we can do about getting older, or our genetic makeup, we can certainly all be more cognizant when it comes to guarding against loud noise exposure. If you work in a constantly noisy environment, you are likely mandated by law to wear hearing protection. If you like listening to music through headphones or earbuds, try turning down the volume. And why not use earplugs when using loud tools or machinery like chainsaws, snow blowers, or lawnmowers around your house? But most importantly – get your hearing tested! With the same frequency that we have our eyes checked, or our cholesterol levels measured, we should have our hearing tested (read more about hearing testing in primary care practices). Changes can happen slowly, over time, and in ways that we barely recognize – until one day we are having a hard time following conversation and find ourselves retreating socially. Hearing loss is the most common disability in the world so if – and when – your hearing starts to change, know that you are not alone. Reach out. Get tested.

Written by: Trevor Griffith