Improving hearing often raises the question of whether a single device provides sufficient benefit. Hearing aids represent an investment, leading many consumers to explore treating only one ear. The decision to purchase a single device requires careful consideration of the underlying hearing profile and long-term auditory health. Using one hearing aid depends entirely on a person’s specific medical condition and the distribution of hearing loss across both ears. Understanding the distinctions between single and dual device use is important for making an informed choice.
Purchasing Options for a Single Device
Consumers are legally permitted to purchase a single hearing aid from a licensed professional or directly from a retailer. The rise of Over-The-Counter (OTC) hearing aids has simplified this process, as these devices are available without a prescription or an appointment. OTC devices are intended for adults with perceived mild to moderate hearing loss and are sold individually or in pairs.
Vendors do not enforce the purchase of a pair. A licensed audiologist can also dispense a single prescription hearing aid if it is determined to be the appropriate course of treatment. The focus should shift from the transactional possibility to the clinical appropriateness for the individual’s hearing needs.
When One Hearing Aid Is Medically Appropriate
A single hearing aid is the preferred treatment primarily for individuals diagnosed with unilateral hearing loss. This condition means that one ear has normal or near-normal hearing, while the other ear experiences a measurable hearing reduction. The loss in the affected ear can range from mild difficulty to a severe reduction in sound detection.
For individuals with mild to moderate loss in one ear, a traditional hearing aid worn on the impaired side can provide the necessary amplification. If the hearing loss in one ear is profound, often termed single-sided deafness, a standard hearing aid may not be effective. In these instances, specialized devices like a Contralateral Routing of Signal (CROS) system may be used, which captures sound from the deaf side and routes it wirelessly to the better hearing ear.
Auditory Consequences of Under-Treating Bilateral Loss
For the majority of people whose hearing loss affects both ears (bilateral hearing loss), choosing to use only one hearing aid can lead to significant clinical disadvantages. The most concerning consequence is auditory deprivation in the unaided ear. This occurs when the auditory system is starved of sound stimulation, and the brain’s ability to process speech signals from that ear declines over time.
Studies have shown that even if the unaided ear is later fitted with a device, the ability to recognize and understand speech may be permanently diminished due to the atrophy that has occurred. The brain relies on input from both ears to accurately process the auditory environment, a function called binaural hearing. When only one ear is amplified, the brain loses the ability to compare the timing and intensity of sounds arriving at each ear.
This loss of binaural processing directly impacts the ability to localize sound sources. It also compromises speech clarity, especially in noisy environments where the brain needs input from both sides to filter out background noise. Using only one aid forces the brain to work harder to compensate for the missing information, which often leads to increased cognitive load and listening fatigue.
Ignoring the need for amplification in one ear when bilateral loss is present constitutes under-treatment and can accelerate the decline of that ear’s function. The long-term benefits of two hearing aids—including better sound quality, improved speech understanding in complex situations, and decreased listening effort—outweigh the initial cost savings of purchasing only one device when both ears are impaired.