Your ear has three main parts: outer, middle and inner. You use all of them in hearing. Sound waves come in through your outer ear. They reach your middle ear, where they make your eardrum vibrate. The vibrations are transmitted through three tiny bones, called ossicles, in your middle ear. The vibrations travel to your inner ear, a snail-shaped organ. The inner ear makes the nerve impulses that are sent to the brain. Your brain recognizes them as sounds. The inner ear also controls balance.

A variety of conditions may affect your hearing or balance:

• Ear infections are the most common illness in infants and young children.
• Tinnitus, a roaring in your ears, can be the result of loud noises, medicines or a variety of other causes.
• Meniere's disease may be the result of fluid problems in your inner ear; its symptoms include tinnitus and dizziness.
• Ear barotrauma is an injury to your ear because of changes in barometric (air) or water pressure.

Some ear disorders can result in hearing disorders and deafness.

Meniere's disease is a disorder of the inner ear. It can cause severe dizziness, a roaring sound in your ears called tinnitus, hearing loss that comes and goes and the feeling of ear pressure or pain. It usually affects just one ear. It is a common cause of hearing loss.

Attacks of dizziness may come on suddenly or after a short period of tinnitus or muffled hearing. Some people have single attacks of dizziness once in a while. Others may have many attacks close together over several days. Some people with Meniere's disease have "drop attacks" during which the dizziness is so bad they lose their balance and fall.

Scientists don't yet know the cause. They think that it has to do with the fluid levels or the mixing of fluids in the canals of your inner ear. Doctors diagnose it based on a physical exam and your symptoms. A hearing test can check to see how it has affected your hearing.

There is no cure. Treatments include medicines to control dizziness, limiting salt in your diet, and taking water pills. A device that fits into the outer ear and delivers air pulses to the middle ear can help. Severe cases may require surgery.

An acoustic neuroma is a benign tumor that develops on the nerve that connects the ear to the brain. The tumor usually grows slowly. As it grows, it presses against the hearing and balance nerves. At first, you may have no symptoms or mild symptoms. They can include

• Loss of hearing on one side
• Ringing in ears
• Dizziness and balance problems

The tumor can also eventually cause numbness or paralysis of the face. If it grows large enough, it can press against the brain, becoming life-threatening.

Acoustic neuroma can be difficult to diagnose, because the symptoms are similar to those of middle ear problems. Ear exams, hearing tests, and scans can show if you have it.

If the tumor stays small, you may only need to have it checked regularly. If you do need treatment, surgery and radiation are options.

If the tumors affect both hearing nerves, it is often because of a genetic disorder called neurofibromatosis.

Anotia and microtia are birth defects of a baby’s ear. Anotia happens when the external ear (the part of the ear that can be seen) is missing completely. Microtia happens when the external ear is small and not formed properly.

Anotia/microtia usually happens during the first few weeks of pregnancy. These defects can vary from being barely noticeable to being a major problem with how the ear formed. Most of the time, anotia/microtia affects how the baby’s ear looks, but usually the parts of the ear inside the head (the inner ear) are not affected. However, some babies with this defect also will have a narrow or missing ear canal.

Barotrauma means injury to your body because of changes in barometric (air) or water pressure. One common type happens to your ear. A change in altitude may cause your ears to hurt. This can happen if you are flying in an airplane, driving in the mountains, or scuba diving. Divers can also get decompression sickness, which affects the whole body.

Common symptoms of ear barotrauma include

• Pain
• A feeling that your ears are stuffed
• Hearing loss
• Dizziness

Treatments for ear barotrauma include chewing gum and yawning to relieve the pressure. Medications such as decongestants may also help.

Ear infections are the most common reason parents bring their child to a doctor. Three out of four children will have at least one ear infection by their third birthday. Adults can also get ear infections, but they are less common.

The infection usually affects the middle ear and is called otitis media. The tubes inside the ears become clogged with fluid and mucus. This can affect hearing, because sound cannot get through all that fluid.

If your child isn't old enough to say "My ear hurts," here are a few things to look for

• Tugging at ears
• Crying more than usual
• Fluid draining from the ear
• Trouble sleeping
• Balance difficulties
• Hearing problems

Your health care provider will diagnose an ear infection by looking inside the ear with an instrument called an otoscope.

Often, ear infections go away on their own. Your health care provider may recommend pain relievers. Severe infections and infections in young babies may require antibiotics.

Children who get infections often may need surgery to place small tubes inside their ears. The tubes relieve pressure in the ears so that the child can hear again.

An ear infection is an inflammation of the middle ear, usually caused by bacteria, that occurs when fluid builds up behind the eardrum. Anyone can get an ear infection, but children get them more often than adults. Five out of six children will have at least one ear infection by their third birthday. In fact, ear infections are the most common reason parents bring their child to a doctor. The scientific name for an ear infection is otitis media (OM).

Our auditory system converts pressure waves into meaningful sounds. This translates into our ability to hear the sounds of nature, to appreciate the beauty of music, and to communicate with one another through spoken language. This section will provide an overview of the basic anatomy and function of the auditory system. It will include a discussion of how the sensory stimulus is translated into neural impulses, where in the brain that information is processed, how we perceive pitch, and how we know where sound is coming from.

Anatomy of the Auditory System

The ear can be separated into multiple sections. The outer ear includes the pinna, which is the visible part of the ear that protrudes from our heads, the auditory canal, and the tympanic membrane, or eardrum. The middle ear contains three tiny bones known as the ossicles, which are named the malleus (or hammer), incus (or anvil), and the stapes (or stirrup). The inner ear contains the semi-circular canals, which are involved in balance and movement (the vestibular sense), and the cochlea. The cochlea is a fluid-filled, snail-shaped structure that contains the sensory receptor cells (hair cells) of the auditory system (Figure).

The ear is divided into outer (pinna and tympanic membrane), middle (the three ossicles: malleus, incus, and stapes), and inner (cochlea and basilar membrane) divisions.

Sound waves travel along the auditory canal and strike the tympanic membrane, causing it to vibrate. This vibration results in movement of the three ossicles. As the ossicles move, the stapes presses into a thin membrane of the cochlea known as the oval window. As the stapes presses into the oval window, the fluid inside the cochlea begins to move, which in turn stimulates hair cells, which are auditory receptor cells of the inner ear embedded in the basilar membrane. The basilar membrane is a thin strip of tissue within the cochlea.

The activation of hair cells is a mechanical process: the stimulation of the hair cell ultimately leads to activation of the cell. As hair cells become activated, they generate neural impulses that travel along the auditory nerve to the brain. Auditory information is shuttled to the inferior colliculus, the medial geniculate nucleus of the thalamus, and finally to the auditory cortex in the temporal lobe of the brain for processing. Like the visual system, there is also evidence suggesting that information about auditory recognition and localization is processed in parallel streams (Rauschecker & Tian, 2000; Renier et al., 2009).

Is your child’s ear hurting? It could be an ear infection. Children are more likely than adults to get ear infections. Talk to your child’s doctor about the best treatment.

Some ear infections, such as middle ear infections, need antibiotic treatment, but many can get better without antibiotics.

What is an ear infection?

There are different types of ear infections. Middle ear infection (acute otitis media) is an infection in the middle ear.

Another condition that affects the middle ear is called otitis media with effusion. It occurs when fluid builds up in the middle ear without being infected and without causing fever, ear pain, or pus build-up in the middle ear.

When the outer ear canal is infected, the condition is called swimmer’s ear, which is different from a middle ear infection.

Causes

A middle ear infection may be caused by:

• Bacteria, like Streptococcus pneumoniae and Haemophilus influenzae (nontypeable)—the two most common bacterial causes
• Viruses, like those that cause colds or flu

See a doctor right away if your child is younger than 3 months old and has a fever of 100.4 °F (38 °C) or higher.

Symptoms

Common symptoms of middle ear infection in children can include:

• Ear pain
• Fever
• Fussiness or irritability
• Rubbing or tugging at an ear
• Difficulty sleeping

When to Seek Medical Care

See a doctor if your child has:

• A fever of 102.2°F (39°C) or higher
• Pus, discharge, or fluid coming from the ear
• Worsening symptoms
• Symptoms of a middle ear infection that last for more than 2–3 days
• Hearing loss

This list is not all-inclusive. Please see a doctor for any symptom that is severe or concerning.

Treatment

A doctor will determine what type of illness your child has by asking about symptoms and doing a physical examination. Your doctor can make the diagnosis of a middle ear infection by looking inside your child’s ear to examine the eardrum and see if there is pus in the middle ear.

Antibiotics are often not needed for middle ear infections because the body’s immune system can fight off the infection on its own. However, sometimes antibiotics, such as amoxicillin, are needed to treat severe cases right away or cases that last longer than 2–3 days.

For mild cases of middle ear infection, your doctor might recommend watchful waiting or delayed antibiotic prescribing.

• Watchful waiting: Your child’s doctor may suggest watching and waiting to see if your child needs antibiotics. This gives the immune system time to fight off the infection. If your child doesn’t feel better after 2–3 days of rest, extra fluids, and pain relievers, the doctor may write a prescription for an antibiotic.
• Delayed prescribing: Your child’s doctor may give an antibiotic prescription but suggest that you wait 2–3 days to see if your child is still sick before filling it.

How to Feel Better

Some ways to feel better—whether or not antibiotics are needed for an ear infection:

• Rest.
• Drink extra water or other fluids.
• Take acetaminophen or ibuprofen to relieve pain or fever. Ask your doctor or pharmacist about over-the-counter medicines that can help you feel better. Always use over-the-counter medicines as directed.

Over-the-Counter Medicine and Children

Be careful about giving over-the-counter medicines to children. Not all over-the-counter medicines are recommended for children of certain ages.

• Pain relievers:
  • Children younger than 6 months: only give acetaminophen.
  • Children 6 months or older: it is OK to give acetaminophen or ibuprofen.
  • Never give aspirin to children because it can cause Reye’s syndrome, a rare but very serious illness that harms the liver and brain.

• Cough and cold medicines:
  • Children younger than 4 years old: do not use unless a doctor specifically tells you to. Use of over-the-counter cough and cold medicines in young children can result in serious and potentially life-threatening side effects.
  • Children 4 years or older: discuss with your child’s doctor if over-the-counter cough and cold medicines are safe to give to your child for temporary symptom relief.

Be sure to ask your doctor or pharmacist about the right dosage of over-the-counter medicines for your child’s age and size. Also, tell your child’s doctor and pharmacist about all prescription and over-the-counter medicines they are taking.

Prevention

You can help prevent ear infections by doing your best to stay healthy and keep others healthy, including:

• Receive recommended vaccines, such as flu vaccine and pneumococcal vaccine. Pneumococcal vaccine protects against a common cause of middle ear infections, Streptococcus pneumonia.
• Clean your hands.

• Breastfeed exclusively until your baby is 6 months old and continue to breastfeed for at least 12 months.
• Don’t smoke and avoid exposure to secondhand smoke.
• Dry your ears thoroughly after swimming.

It's frustrating to be unable to hear well enough to enjoy talking with friends or family. Hearing disorders make it hard, but not impossible, to hear. They can often be helped. Deafness can keep you from hearing sound at all.

What causes hearing loss? Some possibilities are

• Heredity
• Diseases such as ear infections and meningitis
• Trauma
• Certain medicines
• Long-term exposure to loud noise
• Aging

There are two main types of hearing loss. One happens when your inner ear or auditory nerve is damaged. This type is usually permanent. The other kind happens when sound waves cannot reach your inner ear. Earwax build-up, fluid, or a punctured eardrum can cause it. Treatment or surgery can often reverse this kind of hearing loss.

Untreated, hearing problems can get worse. If you have trouble hearing, you can get help. Possible treatments include hearing aids, cochlear implants, special training, certain medicines, and surgery.