Hearing loss
Read the topic background here, then explore the labeled visual and structured learning explanations on this page.
Read explanation on this page ↓ See diagram ↓Hearing loss — on-site reading
An introductory overview for this topic. The article introduction is reproduced here, so you do not need to leave MedAtlas to read it. It may not match the latest official medical guidance.
Hearing loss is either a partial inability to hear, or a total inability termed deafness. Hearing loss may be present at birth or acquired at any time afterwards. Hearing loss may occur in one or both ears. In children, hearing problems can affect the ability to acquire spoken language. In adults, it can create difficulties with social interaction and at work. Hearing loss can be temporary or permanent. Hearing loss related to age usually affects both ears and is due to cochlear hair cell loss. In some people, particularly older people, hearing loss can result in isolation and loneliness.
Hearing loss may be caused by a number of factors, including: genetics, ageing, exposure to noise, some infections, birth complications, trauma to the ear or brain, and certain medications or toxins. A common condition that results in hearing loss is chronic ear infections. Certain infections during pregnancy, such as cytomegalovirus, syphilis and rubella, may also cause hearing loss in the child. Hearing loss is diagnosed when hearing testing finds that a person is unable to hear 25 decibels in at least one ear. Testing for poor hearing is recommended for all newborns. Hearing loss can be categorized as minimal/slight (15 to 25 dB), mild (25 to 40 dB), moderate (41 to 55 dB), moderate-severe (56 to 70 dB), severe (71 to 90 dB), or profound (greater than 90 dB). There are three main types of hearing loss: conductive hearing loss, sensorineural hearing loss, and mixed hearing loss.
About half of hearing loss globally is preventable through public health measures. Such practices include immunization, proper care around pregnancy, avoiding loud noise, and avoiding certain medications. The World Health Organization recommends that young people limit exposure to loud sounds and the use of personal audio players to an hour a day to limit noise exposure. Early identification and support are particularly important in children. For many, hearing aids, sign language, cochlear implants and subtitles are useful. Lip reading is another useful skill some develop. Access to hearing aids, however, is limited in many areas of the world.
How this connects to Otorhinolaryngology (ENT)
The ear, nose and throat form connected sensory and airway systems. Sound conduction, inner-ear transduction, nasal airflow, swallowing and laryngeal function depend on separate structures and cranial nerves, so similar symptoms can arise from different anatomical locations.
Text credit: Wikipedia contributors, “Hearing loss”, original article · authors & revision history · CC BY-SA 4.0. Unmodified opening extract, accessed 24 September 2026. This Wikipedia-derived section is provided under CC BY-SA 4.0; the independent MedAtlas notes and design are separate works.
Hearing loss · visual study map
Scalable vector illustration. Labeled conceptual map, not a precise anatomical, histological or diagnostic image.The wording in this learning map is adapted from the attributed Wikipedia background section below (CC BY-SA 4.0).
What the underlying subject studies
ENT studies the connected anatomy of hearing, balance, upper airway, nose, pharynx and larynx. Structure determines airflow, sound transmission, swallowing and voice production.
How mechanisms and evidence connect
Symptoms can originate at several levels of the auditory, vestibular or aerodigestive system. The examination site, cranial nerves and anatomical compartments help organize the differential.
How to develop a sound explanation
Trace a normal sensory or air passage through its structures, then compare how a broad category of disturbance might interrupt the pathway. Procedure and airway guidance requires specialized training.
References and verification (optional)
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