Hearing Aids

The primary treatment for most hearing loss

Overview

Hearing aids are electronic devices that amplify and process sound for people with hearing loss and are the most widely used treatment for permanent hearing loss. Modern aids are digital: microphones feed a processor that applies frequency specific gain according to the audiogram, compresses loud sounds to keep them comfortable, reduces background noise, and controls feedback. Professional fitting uses prescriptive formulas such as NAL and DSL, often verified with real ear measurement. Styles include behind the ear, receiver in canal, and custom in the ear and completely in canal designs. Common features are directional microphones, Bluetooth streaming, rechargeable batteries, and telecoils. Fitting both ears is typical when both have hearing loss, because it supports localization and listening in noise. The brain usually takes time to adapt to amplified sound. Earlier ear trumpets and body worn transistor aids preceded today devices. Hearing aids improve audibility and communication but do not restore normal hearing.