Electric Acoustic Stimulation (EAS) is an advanced approach for addressing specific forms of hearing loss. It combines two distinct sound processing strategies within a single device. EAS assists individuals with specific patterns of auditory impairment, offering a more comprehensive listening experience.
Understanding Electric Acoustic Stimulation
EAS integrates acoustic amplification and electrical stimulation to process sound across different frequency ranges. An external audio processor with microphones captures sounds. Low-pitched sounds are amplified acoustically, similar to a conventional hearing aid, and delivered through an earmold to the ear canal. This leverages any remaining natural low-frequency hearing.
High-pitched sounds are converted into electrical signals and transmitted to an implanted electrode array within the cochlea. This electrical stimulation activates the auditory nerve, bypassing damaged hair cells that process high-frequency sounds. The inner ear processes these stimuli simultaneously, creating a combined perception of sound. This dual approach ensures access to a wider spectrum of sound frequencies than either technology could provide independently.
Candidacy for Electric Acoustic Stimulation
EAS is for individuals with a specific configuration of hearing loss. Candidates possess usable residual low-frequency hearing, perceiving deeper sounds. They also experience significant to profound sensorineural hearing loss in high frequencies, making it difficult to hear higher-pitched sounds like speech consonants or musical notes. This pattern is sometimes referred to as “ski-slope” hearing loss.
Audiological assessments determine suitability for EAS, involving evaluations of hearing thresholds across various frequencies. Patients considered for EAS have preoperative hearing thresholds of 60 dB hearing level (HL) or less through 500 Hz. This profile makes them suitable for EAS, as a traditional hearing aid cannot sufficiently amplify high frequencies, and a standard cochlear implant might unnecessarily replace their preserved low-frequency hearing.
Life with Electric Acoustic Stimulation
Individuals using EAS report improvements in their daily listening experiences. The combined acoustic and electric input enhances speech understanding, particularly in challenging listening environments with background noise. This helps users differentiate speech sounds more clearly, making conversations more accessible.
The technology also contributes to a richer perception of music, allowing users to appreciate melodic and harmonic details. Many users experience improved sound localization, the ability to identify a sound’s direction. The blend of natural low-frequency hearing with electrically stimulated high-frequency hearing provides a more complete sound quality. An adaptation period and rehabilitation process, involving audiology appointments, optimize device settings and help users integrate both sound inputs for a comprehensive auditory experience.