When hearing aids are recommended, patients frequently ask “Do I really need two hearing aids?”. The answer, the vast majority of the time, is yes. In fact, this is not a new question. A paper from 1962 surveying patients about their experience in various environments demonstrates subjective preference for two hearing aids over one, but it would take several more years before the recommendation for two hearing aids became standard.1 It would be easy to point to a financial motivation for dispensing two devices, but ultimately the recommendation is derived from sound scientific principles.
The first reason for recommending two hearing aids is localization. Localization is the ability to determine where a sound is coming from in space. We have this ability because we are born with two ears. The brain learns to determine where a sound is because it is louder on one side and/or arrives at one ear before it arrives on the other side of the head. Individuals with normal hearing in both ears do this without thinking. Localization is important when you hear your name being called from another room or if you hear something come toward you that is dangerous – like a speeding car or falling object!
Along with localization, two hearing aids help a person to hear in noisy environments. In an interesting study by Starkey (a hearing aid manufacturer) and the University of California-Berkley, tested a person’s ability to understand what they are listening to, not just recite back what they have heard. What they found was an improved ability to comprehend what was being said because of the improvement in sound localization when a subject heard from two ears instead of using only one.2 In order to help a patient meet their goal of improved hearing/understanding in noise, two hearing aids are the most appropriate recommendation.
Using two hearing aids also decreases the amount of gain, or loudness needed. This is accomplished through a biologic phenomenon known as “binaural summation”. In layman’s terms, the brain “adds together” the sound from both ears to make a more robust single sound. You can try this at home! Wear only one hearing aid for a day, and you will often find that you want to turn it up.
When only wearing one hearing aid, the ear without a device risks experiencing auditory deprivation. Several studies have demonstrated that in about 25% of patients who only wear one hearing aid, the word understanding in the ear without a hearing aid declines over time even when how softly they hear tones remains the same. 3 The old adage “If you don’t use it, you’ll lose it” seems to apply here. Audiologists are in the business of preserving hearing and improving communication – which means recommending two hearing aids instead of only one.
Finally, patients who wear two hearing aids are more satisfied and report better sound quality. They appreciate better fullness, brightness, clarity, smoothness and overall impression with two hearing aids when compared to only listening with one. 4
There are situations where an audiologist may only recommend one hearing aid, especially if one ear has significantly poorer hearing than the other ear. Your Audiologist can help decide if you would be a candidate for two or one device. Scheduling your hearing test with an Audiologist at Oklahoma Hearing Center is the first step to improving your hearing. Call us today 405-546-4280 – we look forward to hearing from you soon!
- Dirks, R and Carhart, R. “A survey of reactions from users of binaural and monaural hearing aids.” Journal of Speech & Hearing Disorders. 27(4): 311-322. (November 1962).
- AudiologyOnline Website. https://www.audiologyonline.com/articles/starkey-research-series-binaural-hearing-12978. Downloaded 11/12/2020.
- Hurley, R. “Onset of auditory deprivation”. Journal of the American Academy of Audiology 10: 529-534. (1999).
- Balfour, P and Hawkins, D. “A comparison of sound quality judgments for monaural and binaural hearing aid processed stimuli”. Ear and Hearing. 13:5: 331-339. (October 1992).