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Hearing Loss

Symptoms, Devices, Prevention & Research

Anatomy of the Human Ear

Interrelated structures of the human ear, from left to right: the outer ear, ear canal, eardrum, middle ear, Eustachian tube, inner ear, cochlea, and auditory nerves.

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Anatomy of the Human Ear.
Interrelated structures of the human ear, from left to right: the outer ear, ear canal, eardrum, middle ear, Eustachian tube, inner ear, cochlea, and auditory nerves.
Source: NIH, National Institute on Deafness and Other Communication Disorders

Tinnitus: A Common Symptom

Tinnitus, common in older people, is a ringing, roaring, clicking, hissing, or buzzing sound. It can come and go. It might be heard in one or both ears and be loud or soft. Tinnitus is also common in members of the military who have been exposed to hazardous levels of noise.

Tinnitus is a symptom, not a disease. It can accompany any type of hearing loss. It can be a side effect of medications. Something as simple as a piece of earwax blocking the ear canal can cause tinnitus, but it can also be the result of a number of health conditions.

If you think you have tinnitus, see your primary care doctor. You may be referred to an otolaryngologist—a doctor who specializes in ear, nose, and throat diseases (commonly called an ear, nose, and throat doctor, or an ENT). The ENT will physically examine your head, neck, and ears, and test your hearing to determine the appropriate treatment.


You may have hearing loss without realizing it. Or you may have symptoms such as

  • Earache
  • A feeling of fullness or fluid in the ear
  • Ringing in your ears (called tinnitus)

Find Out More


  • Aging
  • Certain infections, diseases, or conditions (heart conditions or stroke, diabetes, tumors)
  • Certain medicines
  • Genetic disorders
  • A severe blow to the head
  • Loud noise

Assistive Devices

  • Hearing aids—Small electronic devices worn in or behind the ear to help people hear more in both noisy and quiet situations. Hearing aids enable people with hearing loss to listen, communicate, and participate more fully in daily life
  • Cochlear implants—Small, complex electronic devices that can help to provide a sense of sound to people who are profoundly deaf or severely hard-of-hearing. They consist of an external portion that sits behind the ear and a second portion that is surgically placed under the skin.
  • Assisted listening devices (ALDs)—Devices that enable better communicating in day-to-day situations. ALDs can be used with or without hearing aids to overcome distance, background noise, or poor room acoustics. An example is a telephone-amplifying device.


  • Know how much noise is too much.
  • Sounds at or above 85 decibels (dB) can damage your ears. Normal conversation is about 60 dB. Chainsaws, hammers, drills, and bulldozers can be at 100dB or louder.
  • Protect your hearing from loud music from personal music devices and concerts.
  • Wear ear plugs or special earmuffs to prevent hearing loss from dangerously high noise levels.

NIH Research to Results

  • Teams of scientists, supported by the National Institute on Deafness and Other Communication Disorders (NIDCD), are the first to demonstrate, in a variety of animal models, the mechanistic process that occurs during the growth and regeneration of inner ear tip links. Tip links are tiny tethers that connect sensory projections on inner ear hair cells that convert sound into electrical signals. Although tip links break easily, they can repair themselves mostly. The discovery offers a possible mechanism for interventions that could preserve hearing in people whose hearing loss is caused by genetic disorders related to tip link dysfunction.
  • How is it that we can focus on a single speaker in a crowded room where others are also speaking? This so-called "cocktail party" effect is the subject of NIDCD-supported research that has shown how the brain processes speech and how we focus only on the intended speaker. Understanding how the brain encodes speech sounds will inform future studies on management of disorders of hearing, attention, speech, and language.
Read More "Hearing Loss" Articles

Managing Hearing Loss / Symptoms, Devices, Prevention & Research / Screening Newborns / How Loud Is Too Loud? / 10 Ways to Identify Hearing Loss

Spring 2015 Issue: Volume 10 Number 1 Page 9