What happens when someone passes a hearing test with flying colors, but still can’t understand a friend when they mumble? The answer might be auditory processing disorder (APD), a central nervous system condition affecting around 0.5–1.0% of people worldwide. In this article, Ability Central answers your top questions about APD, including:

• What is auditory processing disorder?
• What causes APD?
• Are there different kinds of APD?
• What other conditions mimic or co-exist with APD?
• How is auditory processing disorder diagnosed?
• What are the communication concerns for auditory processing disorder in adults?
• Where can I get more information about APD?

What is auditory processing disorder)?

Auditory processing disorder (APD) is a difference within the central nervous system that affects how a person’s brain interprets what their ears hear. APD is not a learning disorder, an auditory learning disability, a cognition disorder, or a loss of hearing issue, and it is often misunderstood because its symptoms are similar to those found in other disorders. 

Someone with APD may struggle to understand what others say in a variety of settings, from lessons in the classroom to conversations in a noisy restaurant. APD makes it challenging to differentiate between sounds, remember spoken instructions, and understand speech when there’s a lot of background noise.

For example, someone with APD might hear “fourteen” instead of “forty,” or ask someone to repeat themselves multiple times, even in a quiet room. 

The issue here isn’t a person’s hearing. Instead, a person with APD’s brain receives the wrong information from the auditory nerve, the signal center that links what your ears hear to what your brain understands.

Auditory processing disorder is also called:

• APD
• King–Kopetzky syndrome
• Central auditory processing disorder (CAPD) 

While APD can affect anyone, most people with APD start to show signs in childhood or old age. Around 5.1% of children and as many as 23-76% of adults over 55 have APD. 

What causes APD?

Auditory processing disorder often runs in families. Besides genetics, APD may be caused by issues like:

• Central nervous system disorders (stroke, epilepsy, multiple sclerosis, Alzheimer’s disease, etc.).
• Frequent ear infections, particularly in early childhood.
• Head injuries.
• Low birth weight or premature birth.

Are there different kinds of APD?

APD is its own diagnosis, but its symptoms can generally be divided into four areas of weakness:

• Auditory discrimination refers to noticing minor differences between words, like “wish” and “fish” or “bagel” and “bugle”.
• Auditory figure-ground discrimination is the ability to pick out words in a loud, echoing, or noisy environment.
• Auditory memory is your ease at recalling what was said, like remembering a phone number or learning song lyrics you’ve heard, not read.
• Auditory sequencing refers to understanding and recalling the order of words.

What other conditions mimic or co-exist with APD?

Because many symptoms of auditory processing disorder overlap with other disorders, children and adults are sometimes misdiagnosed or may have a coexisting condition along with APD. Other conditions with similar symptoms include:

• Attention Deficit Hyperactivity Disorder (ADHD)
• Autism Spectrum Disorder (ASD)
• Pervasive Developmental Delay (PDD)
• Receptive Language Disorder (RLD)

How is auditory processing disorder diagnosed?

APD often first appears in childhood. Many people may be involved in evaluating symptoms and signs of APD. Typically, parents and teachers are the first to notice symptoms. Your child’s school might recommend testing from a psychologist to rule out cognitive disabilities, or a session with a speech-language pathologist to evaluate verbal and written language skills. 

While many school programs offer early testing for APD symptoms, only an audiologist can confirm an APD diagnosis. Most testing for young children focuses on ruling out other high-level disorders like other language disorders, autism spectrum disorder, or ADHD.

For adults, there is an online assessment that may help. The Adult Auditory Performance Scale (AAPS) tests your listening abilities across six categories:

• Noise
• Quiet
• Ideal
• Multiple inputs
• Auditory memory/sequencing
• Auditory attention span

The AAPS is not a diagnostic tool, but may recommend you get your hearing tested.

Both children and adults will need to see a hearing specialist called an audiologist for an actual diagnosis. An audiologist uses specialized tests to evaluate: 

• The brain’s ability to process sounds effectively. 
• Any specific processing deficits.
• Crucial insights that might guide the development of personalized treatment plans. 

After diagnosis, the next step in the APD journey is customized treatment. Your doctor or your child’s school may have a list of specialists to assist with diagnosis and treatment. Ability Central also maintains a list of nonprofits specializing in hearing disorders like APD that can connect you with support and services in your area.

What are the communication concerns for auditory processing disorder in adults?

Since the brain isn’t interpreting hearing accurately, adults with APD may experience difficulty:

• Understanding conversations.
• Having conversations in noisy environments.
• Multitasking.
• Comprehending fast speech.
• Following long conversations.
• Understanding without relying on lipreading or facial cues.
• Making sense of unfamiliar accents.
• Following along during teleconferences.
• Remembering information long enough to write it down.
• Understanding sarcasm, tone of voice, or jokes.
• Understanding music lyrics.

In a remote work setting, emails or texts are more accessible for a person with APD to process than a telephone call. If a call is required, consider a video call service. Utilizing a mobile device specifically designed for APD can help. Whether you need a larger screen, voice-to-text ability, or email access in a quiet setting, see Ability Central’s database of mobile devices with accessibility features that support adults with APD.

Where can I get more information about APD?

To learn more about APD, see:

• What are the Early Symptoms of Auditory Processing Disorder (APD)?
• The Most Important Things to do After an Auditory Processing Disorder (APD) Diagnosis
• Living With Long-term Auditory Processing Disorder (APD)

To learn about similar or co-existing conditions, see:

• Attention Deficit Hyperactivity Disorder (ADHD)
• Autism Spectrum Disorder (ASD)
• Dyslexia
• Dysgraphia
• Dyscalculia
• Pervasive Developmental Delay (PDD)
• Receptive Language Disorder (RLD)
• Stroke