50+ Lifestyles

Hearing With Two Ears

By Ali Hunt
Parker Audiolology Extern

Do you recall a time when you were driving down the road and you heard the siren from an emergency vehicle? Your ears and brain work together to decipher timing and loudness differences as the sound reaches the ears to locate which direction that siren is coming from. Hearing with only one ear makes finding that siren far more difficult.

Hearing care providers will often recommend two hearing aids for patients exhibiting a hearing loss in both ears.  A frequent question asked is, “Do I really need a hearing aid for both ears?” Hearing loss differs from patient to patient, and recommendations for amplification will vary according to the individual’s needs. Nonetheless, it is important to understand the importance of hearing with two ears, or binaural hearing.

In addition to locating sound sources, using two ears helps you hear better in noise. Your ears work together to filter out some background noise and focus more on the speech you want to listen to. Hearing aids often feature directional microphones to further help you to hear speech within background noise.

Hearing loss can be a cause of stress and fatigue from straining to hear clearly. Utilizing two hearing aids helps alleviate the effort needed to hear speech. Furthermore, binaural hearing can help provide a balanced sound quality. The effect of using two hearing aids instead of one has a stereo effect, resulting in a fuller, more natural sound.

When One Ear is Dead…

Some patients have significant hearing loss in one ear and cannot use amplification with much benefit. One case is called single sided deafness (SSD), where the patient has normal hearing in one ear and no functional hearing in the other.  In this instance, a conventional hearing aid is not an appropriate solution, but a hearing device called Contralateral Routing of Signal (CROS) may help.

The CROS system involves two devices, one worn on each ear.  The device worn on the “bad” ear is simply a microphone that picks up sound on that side. The signal is wirelessly transmitted to the receiver worn on the “good” ear.  This system allows the patient to hear speech and environmental sounds from the poorer hearing side.  Studies have shown patients with single sided deafness to have an improvement in hearing speech in noise from the CROS devices, but sound localization typically is not restored (Ryu, Moon, Byun, Jin, Park, Jang, and Cho, 2015). Thus, the CROS devices are an excellent treatment solution for those patients with hearing loss greatly affecting one ear.

There are several new treatment options recently available.  Call Parker Audiology today at 563-326-5441  to schedule your complimentary hearing consultation.

Please join us at the St. Ambrose Professional Development Downtown Education Center to learn about treatment solutions when you have a dead ear. Call us to RSVP your spot on Wednesday, March 16 at 1 pm.

Reference:
Ryu, N., Moon, I., Byun, H., Jin, S., Park, H., Jang, K., & Cho, Y. ( 2015).  Clinical effectiveness of wireless CROS (contralateral routing of offside signals) hearing aids. European  Archives of Otorhinolaryngoogy, 272, 2213-2219. DOI 10.1007/s00405-014-3133-0.

Ali Hunt is an audiology extern at Parker Audiology. She will graduate with a doctorate in audiology from Washington University School of Medicine in St. Louis in May, 2016.