How Do Hearing Aids Work?

Most hearing loss affects certain frequencies more than others, often the higher pitches used in speech. A modern digital hearing aid converts sound into data and boosts only the frequencies the wearer struggles to hear, according to a programmed hearing test. Processors can reduce background noise, prevent feedback whistling and use directional microphones to focus on the person in front. Many connect wirelessly to phones and TVs. For profound deafness where hair cells are badly damaged, cochlear implants instead stimulate the hearing nerve directly with electrodes.