A person can purchase a single hearing aid, but this decision requires careful consideration by a hearing healthcare professional to determine if it is the optimal choice. Fitting a hearing aid to only one ear is known as a monaural fitting, often pursued to balance the medical necessity of treatment with the high cost of the devices. While a monaural fitting may provide some benefit, audiologists generally recommend two devices, called a binaural fitting, when hearing loss affects both ears. The dilemma involves navigating the significant difference in price versus the benefits of treating both ears.
Auditory Science: Why Most People Need Two Hearing Aids
Hearing is a complex function of the brain, not just the ears, and the brain relies on receiving information from both sides to process sound effectively. When hearing loss is present in both ears, wearing two hearing aids helps preserve the natural way the brain works by providing balanced stimulation to the auditory pathways. This bilateral input allows the brain to combine the signals into a clearer, richer sound experience, a benefit known as binaural summation.
The dual input from two ears significantly improves an individual’s ability to locate the source of a sound, a process called sound localization. The brain uses the subtle differences in the timing and intensity of a sound as it reaches each ear to pinpoint its direction, which is important for safety and awareness. When only one ear is aided, sounds originating from the unaided side are blocked by the head, creating an acoustic shadow effect that makes localization difficult and forces the brain to strain to hear.
The strain of constantly trying to fill in missing auditory information leads to listening fatigue. Using two hearing aids reduces this cognitive load by distributing the work of hearing between both ears, resulting in less mental exhaustion. Bilateral fitting also helps prevent auditory deprivation, where the brain’s ability to process sound from the untreated ear declines due to lack of stimulation. The principle of “use it or lose it” applies directly to the neural pathways responsible for hearing.
Specific Cases Where One Hearing Aid Is Justified
While two hearing aids are the standard recommendation for bilateral hearing loss, there are specific audiological profiles where a monaural fitting may be appropriate. The most straightforward case is unilateral hearing loss, where one ear has normal hearing and only the other ear requires amplification. A single hearing aid is also justified when a person has a profound or complete loss in one ear that cannot be functionally helped by a traditional device, often referred to as a non-aidable ear.
Specialized Systems for Asymmetrical Loss
Individuals with single-sided deafness or highly asymmetrical hearing loss often use specialized systems that technically involve two devices but serve a single-ear function. The Contralateral Routing of Signal (CROS) system uses a microphone on the poor ear to wirelessly transmit sound to a receiver worn on the good ear. A BiCROS system is used when the poor ear is unaidable and the better ear still requires some amplification due to a mild or moderate loss.
When the cost of two devices is prohibitive, an audiologist may agree to a monaural fitting to provide at least partial treatment. This is not the ideal solution when both ears could benefit, but it ensures the patient receives some level of hearing support.
The Financial and Practical Process of Buying Hearing Aids
The primary motivation for purchasing only one hearing aid is the financial investment involved. The cost of a single prescription hearing aid can range from approximately $1,500 to over $4,150, depending on the technology level and bundled services. While the second device in a pair may sometimes be discounted, the total price remains a substantial hurdle, as most health insurance plans offer limited or no coverage.
Regardless of whether a person buys one or two devices, the process begins with an audiological assessment and a professional fitting. This ensures the device is correctly programmed to the individual’s specific hearing profile and that the physical fit is comfortable and secure. The price typically includes professional services like initial fitting, follow-up adjustments, and aftercare.
Most hearing aid purchases include a trial period, which allows the user to test the device in their everyday environments. This period is important for those considering a monaural fitting, as it provides an opportunity to experience the difference between hearing with one aid versus two. This experience can help confirm the best long-term solution.