Auditory processing disorder (APD)

Auditory processing disorder (APD) is a condition that affects how the brain processes sound. It also is called central auditory processing disorder (CAPD). This condition can happen in children and adults.

With APD, hearing tests may not show hearing loss. But you may have trouble making sense of what you hear. APD is different from hearing loss caused by an issue with the outer, middle or inner ear. It's also not the same as hearing loss caused by an issue with the auditory nerve, the nerve that leads from your ears to your brain.

Many conditions can affect how well you understand what you hear. Attention-deficit/hyperactivity disorder (ADHD) and autism are examples. These conditions are different from auditory processing disorder, but they can appear with APD. APD also can happen with other types of hearing loss.

There is no cure for APD, but treatments can help.

Symptoms of auditory processing disorder (APD) can vary and be subtle. Symptoms can include trouble with being able to:

• Tell where a sound is coming from.
• Understand words that are spoken quickly or in a noisy room.
• Follow directions that aren't short and simple.
• Sing or recognize patterns in music.
• Understand and remember what you hear.

When to see a doctor

If you have trouble understanding what you hear, talk to a healthcare professional.

The cause of auditory processing disorder (APD) is often unknown. APD can be linked to many conditions. In adults, it may be linked to conditions such as stroke, traumatic brain injury or age-related changes. In children, APD can be linked to issues at birth, such as an early birth or low birth weight. APD also can be linked to repeated ear infections.

When hearing works as expected, the brain's auditory center takes sound waves sent from the ears and turns them into sounds you know. But with APD, the auditory part of the brain can't do this.

Factors that may raise your risk of auditory processing disorder (APD) include:

• Aging.
• Stroke.
• Head trauma.
• Issues linked to birth, such as an early birth, low birth weight, or use of alcohol, drugs or tobacco during pregnancy.
• Repeated ear infections, especially at a young age.

Other conditions that have been linked to APD include:

• Dementia.
• Migraine headaches.
• Parkinson's disease.
• Brain tumors.

Complications of auditory processing disorder (APD) include issues with:

• Paying attention, especially in distracting environments.
• Understanding others.
• Learning new languages or new words.
• Taking part in activities.
• Doing well in school.
• Reading and writing, especially in children.

APD also may cause you to:

• Take longer to reply to someone who is talking to you.
• Often need others to repeat themselves.
• Not understand sarcasm or jokes.
• Feel isolated and lonely.
• Feel frustrated and depressed.

To diagnose auditory processing disorder (APD), your healthcare professional may ask questions about your symptoms and how long you have had them. You also may have tests.

Many specialists may help diagnose APD. They may include a hearing specialist called an audiologist, mental health professionals and speech-language pathologists. For children, teachers also may be involved.

A diagnosis of auditory processing disorder starts with tests to check for hearing loss. These tests may include:

• Tympanometry. This test checks how well the eardrum and middle ear work. This test can tell if the eardrum isn't moving well. The eardrum needs to move for good hearing. For this test, the audiologist places a soft probe in the ear canal and sends small bits of air pressure toward the ear. The probe measures how much the eardrum moves in response to the air.
• Acoustic reflex testing. This test shows what happens in the ear when you hear a loud sound.
• Evoked potential tests. These tests show how the brain responds to sounds. An example is an auditory brainstem response test. This test measures how sound travels from the ear to the brainstem and along the auditory pathways. An audiologist places sensors around your ear and on your head. You hear short clicking sounds through headphones. A computer records how the nerves between the ears and the brain respond to the sounds.

If these tests show that you don't have hearing loss, you then have other tests to show if you have auditory processing disorder. You may hear these tests called central auditory tests. They include:

• Speech-in-noise. This test checks how well you understand speech when there is background noise. You hear words or sentences. Background noise is played at the same time. The test measures how much noise you can handle and still understand what you hear.
• Dichotic listening. This test checks how well your brain can process different sounds sent to each ear at the same time. For this test, you wear headphones. Sounds are sent to one or both ears. You are asked to repeat what you hear.
• Temporal processing. This test checks how well your brain handles the timing of the sounds you hear. You hear simple sounds such as beeps or tones. Then you are asked how many sounds you heard and their pattern, such as high, low, high.

Together, these results show how well the brain processes sound.

Your healthcare team also may test for attention disorders such as attention-deficit/hyperactivity disorder (ADHD). These conditions share symptoms with APD, such as trouble with listening, following directions and keeping focus. They're not the same as APD, but they may happen at the same time.

Not everyone with auditory processing disorder (APD) needs treatment. If you or your child needs treatment, there are many approaches. Treatment is based on each person's specific needs.

Treatment may include:

• Hearing aids and listening devices. Your healthcare team may suggest that you use hearing aids with wireless listening devices. Listening devices help direct sound to you. They get sound from the source to your hearing aid.
• Frequency modulated (FM) systems and digital modulation (DM) systems send sounds to you so you can hear them better. They work with a hearing aid and direct sounds to it. These systems help make it easier to hear sounds in noisy environments.

• Auditory training. Auditory training helps you better process and understand sounds. You may hear it called hearing rehabilitation. Training may be done with an audiologist, a speech-language pathologist or both. You may have training one-on-one with a therapist or as part of a group.

  During auditory training, you learn to tell one type of sound from another. You do this by listening to sounds that are louder and softer, given quickly and slowly. The sounds may come from different directions. You also learn to tell the difference between speech sounds, which affect the meaning of the words you hear.

  Auditory training helps the brain tell the difference between the many sounds you hear every day. The goal is to help you communicate more easily with others.

• Computer-based training. Computer-based programs can help train the brain to pick out and understand sounds. These programs work much like auditory training does. You can do this training at home.

There are simple steps you can take to manage auditory processing disorder (APD). For instance:

• Try using a remote microphone to improve how well you can hear in a noisy room.
• Move closer to the person who is speaking.
• Cover hard surfaces that make sounds echo, such as bare floors, with materials that absorb sound.
• Move away from other sources of noise, such as a fan.
• In a class or at a meeting, ask someone to take notes for you, or get a written copy of what was said.
• Ask for anything important to be in writing instead of only spoken.
• Use captions or subtitles when watching TV or videos.

Auditory processing disorder (APD) may make you feel left out of everyday events. It also can make you feel lonely. Auditory training as part of your treatment may help you or your child cope and adjust to this condition.

Auditory training might help you or your child learn to communicate with others better and help others communicate with you. This can help you feel less alone and more connected to others.

You or your child might start by seeing your family healthcare professional. For testing, you might be referred to a specialist in hearing, called an audiologist.

Here's some information to help you get ready for your appointment.

What you can do

Make a list of:

• Symptoms, including any that don't seem linked to the reason for your appointment, and when the symptoms began.
• Key personal information, including major stresses, recent life changes and family medical history.
• All medicines, vitamins or other supplements you or your child take, including the doses.
• Questions to ask your healthcare professional.

Take a family member or friend along, if possible, to help you hear or remember the information you get.

For auditory processing disorder, some basic questions to ask include:

• What's likely causing my or my child's symptoms?
• Other than the most likely cause, what are other possible causes for these symptoms?
• What tests are needed?
• Is this condition likely to go away or be long-lasting?
• What treatments are available?
• Could this condition be related to other issues I am having?
• How can I cope with this condition at school, work or home?
• Is there more information I can have? What other sources of information would you suggest?

Be sure to ask all the questions you have about this condition.

What to expect from your doctor

Your healthcare team is likely to ask you questions, such as:

• Are the symptoms constant, or do they come and go?
• How bad are your symptoms?
• What, if anything, helps you hear better?
• What, if anything, makes it harder for you to hear?