Hearing Aids: Prescriptions, Selection, Fitting, and Verification

Vocabulary flashcards covering hearing aid programming, candidacy, prescriptive targets, amplitude compression, verification procedures, orientation, and maintenance.

Analog Hearing Aid

A hearing aid that utilizes an electrical circuit to modify and amplify sound.

Digital Hearing Aid

A hearing aid that processes and modifies acoustic signals using a computer circuit.

Programmable Hearing Aid

An analog or digital hearing aid whose operational settings and acoustic parameters can be adjusted via a computer.

Hearing Aid Fitting Range

The specific region of degrees and configurations of hearing loss on an audiogram that a designated hearing aid model can appropriately fit.

Gain

The amount of amplification, measured in decibels, provided by a hearing aid to an incoming signal.

Maximum Power Output (MPO)

The maximum sound pressure level that a hearing aid can deliver to prevent discomfort or acoustic trauma.

Prescriptive Target

A calculated electroacoustic goal generated by a fitting formula designed to improve speech audibility or normalize loudness perception.

Desired Sensation Level (DSL)

An audibility-based prescriptive target formula primarily utilized in pediatric hearing aid fittings to maximize speech intelligibility.

NAL-NL2

A loudness-based prescriptive target algorithm designed by the National Acoustics Laboratory to optimize speech intelligibility while maintaining overall loudness comfort.

Recruitment

An abnormal, disproportionately rapid growth in perceived loudness characteristic of sensorineural hearing loss.

Dynamic Range (Auditory)

The decibel span between an individual's hearing threshold and their uncomfortable loudness level, which becomes narrowed in individuals with sensorineural hearing loss.

Amplitude Compression

An electroacoustic process that automatically decreases hearing aid gain as input sound levels increase, maintaining comfort and audibility.

Compression Limiting

A compression strategy that applies linear amplification across the speech range (such as providing $20\,\text{dB}$ of gain for soft and moderate sounds) and applies heavy compression only at high input intensities.

Wide Dynamic Range Compression (WDRC)

An amplitude compression scheme where compression begins at low input levels below typical conversational speech, maintaining listening comfort across a broad range of inputs.

Hearing Aid Verification

The objective clinical assessment performed to ensure that the hearing aid provides adequate audibility, controls loudness, and executes advanced feature functions (such as noise reduction and feedback suppression) properly.

Real Ear Measures (REM)

Objective acoustic measurements recorded directly in a patient's ear canal using a probe microphone, providing high accuracy and enabling feedback assessment.

Coupler Measurement

An objective verification measurement performed inside an acoustic cavity (such as a 2-cc coupler) that does not require an active, cooperative patient.

Real-Ear-to-Coupler Difference (RECD)

The measured difference in decibels between the sound pressure level generated in the individual patient's ear canal and that produced inside a standardized coupler.

APHAB

Abbreviated Profile of Hearing Aid Benefit; a validated self-report outcome questionnaire assessing hearing disability and aid benefit across different listening scenarios.

COSI

Client Oriented Scale of Improvement; an open-ended clinical assessment tool in which the patient identifies specific listening goals and rates their perceived improvement after hearing aid fitting.

Hearing Aid Orientation

A form of informational counseling guiding the patient through realistic hearing expectations, device operation, routine care, and troubleshooting.

BASICS Framework

An instructional checklist for patient hearing aid orientation covering Batteries, Acoustic feedback, System troubleshooting, Insertion and removal, Cleaning and maintenance, and Service.

Acclimatization

The neurological and auditory adaptation process to newly amplified sound, which typically requires up to $3\,\text{months}$ of consistent, full-time device use.

Hearing Aid Listening Check

A routine functional test using a stethoscope or listening tube before an auditory rehabilitation session to determine whether a hearing aid is dead, intermittent, or distorted.

Ling 6 Sounds

A specific battery of phonemes (/ɑ, i, u, s, ʃ, m/) that represent low, middle, and high speech frequencies, utilized during hearing aid listening checks and speech detection tests.

Over-the-Counter (OTC) Hearing Aids

FDA-approved direct-to-consumer amplification devices designed for adults with perceived mild to moderate hearing loss that do not require medical clearance or an audiological evaluation.