Hearing loss in one ear

Jul 27, 2020Hearing Loss

Unilateral Hearing Loss

Generally hearing loss affects both ears at the same time.

However, there are times where just one ear experiences hearing loss (unilateral hearing loss) or one ear has worse hearing than the other ear (asymmetric hearing loss). If this applies to you, the first thing you need to do is book yourself in for a hearing test and then see your doctor to discuss the results. This is to rule out any medical issues that could be causing your unilateral or asymmetric hearing loss.

What is the big deal about having hearing loss in one ear?

A lot of the time it does not seem like a big problem if one ear is still able to hear normally. But for a lot of people with unilateral hearing loss or asymmetric hearing, there are unique hearing challenges that are experienced. Aside from the obvious challenge of being unable to hear sound on the side with the hearing loss, the main challenges experienced with asymmetrical hearing loss include sound localisation and hearing conversation in background noise.

Sound localisation is the ability to tell which direction a sound is coming from. The brain relies on information coming from both ears to work out where a sound is in the horizontal plane. If one ear does not hear as well as the other ear, these slight differences can become skewed and the brain can get confused about which direction a sound is coming from.

The other challenge associated with unilateral hearing loss is hearing what you want to hear in a noisy room. The ability to focus on one conversation in a crowded room is very complex and relies on having both ears working optimally. The sound localisation cues discussed above also contribute to hearing ability in a noisy place. There are also other signals that rely on both ears working optimally to help the brain work out what you want to listen to and what is background noise. When the brain is hearing the same thing in both ears, in a way it is hearing the same thing twice. There is a better chance of identifying what you want to listen to and what is background noise with two ears working properly than when only one ear is relaying information to the brain. Everything also sounds a bit louder when you are listening with two ears compared with just one ear, which also gives you a better chance of hearing in a noisy place.

What options are available to help me if I have hearing loss in one ear?

The amplification options that are currently available are designed to try to overcome the impact of hearing loss on sound localisation and listening in background noise. There are a variety of options that may be suitable for different individuals. These include hearing aids, implants or wireless accessories.

Hearing aid for the poorer ear

Fitting a hearing aid to the ear with hearing loss is an option for people who can still obtain meaningful information from their worse ear. The speech test that forms part of a standard hearing test can give an idea about whether increasing the volume will result in better hearing ability for conversation. If the ear with hearing loss can hear words clearly when they are made louder, having just one hearing aid may be beneficial to balance the ear with hearing loss with the better ear.

A hearing aid is programmed specifically for your hearing loss and aims to give more volume to the sounds that are difficult to hear. This strategy aims to improve the brain’s ability to use sound from both ears to work out the direction that sound is coming from as well as to help with hearing conversation in background noise. It is an option that is suitable for a mild hearing loss right down to a profound hearing loss.
For people who have hearing issues as a result of a disruption to the auditory nerve, speech or just sound in general can sound distorted in the affected ear. For these cases, a hearing aid is not recommended. This is because it just does not provide any benefit compared with not wearing a hearing aid. Or worse still, it will make the distortion louder and cause greater hearing problems. The more suitable hearing aid option in this case is a CROS system.

CROS system

CROS stands for Contralateral Routing of Signal and is the more commonly recommended hearing aid option when one ear cannot be aided with a traditional hearing aid. It consists of two parts, a microphone that is worn in the poorer ear and a hearing aid that is worn in the better ear. Sound is picked up on the poorer side by the microphone and is sent across wirelessly to the hearing aid in the other ear. This enables the better ear to hear sound that originates from the side of the poorer ear.

For individuals with normal hearing in the better ear, the system is called a CROS. A hearing aid is still needed for the better ear to receive the sound from the CROS microphone, but it will provide little to no amplification. For individuals with hearing loss in the better ear, the system is called a BiCROS. The hearing aid in the better ear is adjusted specifically for the hearing loss in this ear. The CROS and BiCROS mainly bring back awareness of sound on the poorer side. They also allow you to hear what someone is saying if they are sitting on the side of your bad ear.

CROS systems are continually improving and now carry a lot of the features that are available in traditional hearing aids. These include wireless connectivity and audio streaming from mobile phones or other bluetooth electronic devices straight to the hearing aid. Wireless connectivity also enables data sharing between the hearing aid and CROS satellite microphone. This allows information from both ears to be used by the sound processing system of the hearing aid, particularly for listening in a noisy place. This mimics how the brain processes the information that it receives from two ears to help filter out background noise. The more recently released CROS systems therefore aim to improve the listener’s ability to hear the conversation that they want to hear in a noisy environment.


For individuals who have tried hearing aids with no success, there are two implant options that might be worth considering: the BAHA (bone-anchored hearing aid) and the cochlear implant.

Although the BAHA’s name suggests it is a hearing aid, it is actually an implant system. A sound processor is worn on the poorer side and sends sound to the better ear through bone vibrations. This principle is similar to that of the CROS where the better ear is hearing sound from the poorer side. The device can be trialled on a headband before undergoing any surgery to ensure that this option works for you.

Cochlear implants are becoming a more common amplification option for people with significant hearing loss in just one ear. Cochlear implants involve surgical insertion of some electrodes into the cochlear that stimulate the auditory nerve directly. A processor is worn behind the ear to pick up sound which is then converted and sent to the brain as an electric signal rather than an acoustic signal. By giving back hearing to the bad ear, the brain can use cues from both ears again and there can be an improvement in sound localisation and listening ability in background noise. However, the success of a cochlear implant relies on an intact auditory nerve amongst a number of other factors and not everybody with hearing loss is a candidate for a cochlear implant. Further information can be found at https://www.cochlear.com/au/home or through your local cochlear implant clinic.

Wireless communication devices

Wireless communication devices relay conversation directly to your ear through a hearing aid or earpiece. They can be thought of as wireless microphones that are placed near the person you want to listen to. These devices allow you to hear them as though they are right next to you speaking into your ear even though they are at the other side of a room or the other side of a table.

Wireless communication devices may be helpful for any level of hearing loss. This is because they can be used in conjunction with hearing aids or an earpiece for very mild hearing loss. Each hearing aid manufacturer will have their own version of a wireless communication device that will work with their brand of hearing aids. There is also the Phonak Roger™ suite of devices with a range of options for different situations that may also be suitable.
Situations where these devices can be useful include lectures or meetings where there is a main speaker who is standing on a stage some metres away. Wireless communication devices are a great option to hear conversation in the car where lip-reading is impossible and road noise drowns out conversation. The device can also be used at a café or restaurant where it is very noisy. You will still hear background noise when using the device, but the advantage is that the speaker will be easier to hear because their voice will not get lost amongst all the other noise and will be heard directly in your ear.

Next steps

There are a range of options available that are suitable for various communication needs and lifestyles. A discussion with one of our audiologists can help you to work out which option or combination of options might work best for you. Feel free to contact us if you have any questions or to arrange a trial of one of these devices.

Share This