What Is Auditory Processing Disorder?
Up to twelve percent of children have diagnosed or undiagnosed auditory processing disorder, a condition that inhibits the brain’s ability to translate and process sounds. Learn more about common signs and symptoms.
Do everyday instructions, requests, and questions seem to bounce off your child? Like he’s living in a bubble that is impenetrable by oral directions? If your child responds most of the time with a blank stare or “Wait, what?” then you know what we’re talking about.
Or perhaps you’ve noticed this yourself — that the world feels “garbled,” like you’re listening to a cell phone call with the signal cutting in and out?
These are signs of auditory processing disorder (APD), a learning disability that impacts the brain’s ability to filter and interpret sounds. People with APD have a hard time receiving, organizing, and using auditory information. They’re able to hear, but fall short at listening. While APD isn’t as well known as some other learning disabilities, it is estimated that 7 percent of children have some type of auditory processing difficulty.
APD is a diagnosis that encapsulates three areas of disability. Lois Kam Heymann describes them this way, “The first problem occurs in the brain’s analysis of the auditory signal. The ears hear normally and send information through the auditory pathways to the central auditory nervous system, but as the signal travels, the brain has trouble discriminating between the acoustic characteristics of the sound received. It doesn’t recognize how an ‘S’ sound is different form a “B” sound, for example.
“The second problem occurs during analysis of the linguistic-phonemic auditory signal. The brain has trouble blending the sounds of the letters to understand a word, and store its meaning. The sound of C-A-T does not translate to a type of animal, for example.
“The third problem involves processing the meaning of language. This is how we associate the sound of the word cat with an image of the furry thing on the living room floor.” When one of these processes is interrupted for a person with APD, it causes a disconnect between what was said, and what was understood.
Symptoms of APD
But what does APD look like, exactly? At its most general, APD is a glitch in the brain’s ability to filter and process sounds. A person with APD doesn’t have difficulty hearing necessarily. Rather, her brain perceives sounds incorrectly, affecting her ability to distinguish between similar sounds (da and ga, for example). Some common signs of APD, according to Lois Kam Heymann, M.A., CCC-SLP are:
- Saying “Huh?” and “What?” often
- Difficulty following multi-step directions
- Difficulty hearing in noisy environments
- Mishearing sounds or words
- Delayed language development
- Distracted and inattentive behavior
- Potentially poor social skills
- Difficulty learning to read
- Poor spelling
- Seems to be missing information
Some children with APD have trouble screening out background noise, so they pick up on and are distracted by bits of surrounding sounds. The echo in a gymnasium or the hum of an air conditioner interferes with the conversation or lesson at hand. It’s like listening to the radio with interference garbling the reception.
A child with the disorder typically tries so hard to understand what’s being said that she forgets parts of the conversation or doesn’t pick up on the nuances or subtleties of the words. This can cause innumerable difficulties in school, at home, and in day-to-day life as the child’s ability to listen, remember, and respond to what is being said is compromised.
Types of APD
Jack Katz, M.D., a pioneer in the field of auditory processing disorder, says that APD comprises three distinct conditions that often overlap but may occur in isolation.
- Sound discrimination problems. When children learn to talk, they mimic the sounds they hear to produce speech. A person with APD may not speak clearly, using similar (“dat” instead of “that”; “free” instead of “three”) rather than exact sounds long after peers have corrected themselves. Typically, people with faulty sound discrimination will run words together or drop word endings and un-emphasized syllables when speaking. Reading and spelling may also be affected.
- Auditory memory problems. This part of the disorder makes it difficult for a child to memorize numbers and facts, and also affects his reading and language skills. Children with auditory memory problems typically take longer to learn their telephone numbers and addresses, and have difficulty remembering basic math facts. Verbal instructions and lists are similarly tough to retain.
- Language processing problems. This component of APD is the most troublesome. It affects a child’s abilities to understand what’s being asked of him and to socialize with peers. A child with this cognitive glitch has trouble taking oral tests and becomes confused when reading and telling stories with lots of characters and events. He will often pass up a chance to hold a conversation because of the time it takes to process words being spoken and to formulate responses.
APD and ADHD
Some studies suggest that 50 percent of individuals diagnosed with ADHD may also have APD. Other studies say that APD exists with another condition 60 percent of the time — most commonly with ADHD, sensory integration disorder, visual processing disorder, and executive function deficits. In other words, symptoms of APD and ADHD often overlap. Just as difficulty filtering and processing sounds can affect a child’s ability to focus, so too can ADHD symptoms affect APD. Some experts even believe that APD is a manifestation of ADHD, though most contend they are separate disorders.
Generally, people with ADHD exhibit inattention, distractibility, and/or hyperactivity and impulsivity in all environments. Children with APD, on the other hand, may appear distracted in noisy environments, but usually don’t have difficulty focusing and paying attention in a quiet space. Many children with APD are exquisitely sensitive to sound. In fact, some say they experience pain when they hear certain sounds – a blender, a train engine, or police sirens, for example.
“Children with ADHD may be poor listeners and have difficulty understanding or remembering verbal information,” explains Teri James Bellis, author of When the Brain Can’t Hear, but “it is the attention deficit that is impeding their ability to access or to use the auditory information that is coming in,” not the processing of it in the brain.
The following characteristics of APD, from the National Institute on Deafness and Other Communication Disorders, sound similar to the symptoms of ADHD:
- Has trouble paying attention to and remembering information presented orally
- Has problems carrying out multi-step directions
- Has poor listening skills
- Needs more time to process information
- Has behavior problems
- Has difficulty with reading, comprehension, spelling, and vocabulary.
Children with ADHD may be misdiagnosed with APD and vice versa, but if an adult has subpar listening ability, he may be perceived as passive-aggressive, oppositional, withholding emotionally, or argumentative, rather than as an individual with attention deficit or an auditory processing deficit.
Causes of APD
The underlying cause of APD isn’t known. Experts debate whether heredity or environment — or both — are responsible for the condition. While the human auditory system is fully developed at birth, auditory pathways don’t mature until the age of 12. Because of this, early influences — such as poor prenatal nutrition, a mother’s exposure to cigarettes or alcohol, childhood malnutrition, and chronic ear infections — may negatively affect auditory processing. Premature birth, Lyme disease or other brain infections, closed head injury, and exposure to low levels of heavy metals (lead or mercury) may also play a role. The good news is that, because the auditory pathways continue to develop up until adolescence, APD is especially responsive to early intervention.
Remember that “not all language problems are due to APD, and not all cases of APD lead to language and learning problems,” Bellis says.
The only way to diagnose the condition is with a battery of tests including the CAP (central auditory processing test), performed by an audiologist who monitors the child’s hearing as he or she listens to words and sentences as background noise is slowly increased and to instructions spoken at faster speeds.
A child should be at least 6 or 7 years old before undergoing testing. “The symptoms you commonly see in a 3 or 4 year old are sound sensitivities and difficulties discriminating between sounds, which you’ll hear in their speech,” explains Wendy Tepfer, a speech and language pathologist in New York City.
When a child reaches school age, however, Tepfer says APD may begin to compromise academic success. “At that age, I would recommend evaluation for APD,” she says, “because now, it’s not only the language but also his performance in the classroom (that may be clues). To manage the disorder, the student may need remediation other than speech and language therapy. A full evaluation will help you know what those are.”
Most people are diagnosed between ages 8 and 12, but therapy can still help older children and adults.
Treatment Options for APD
APD can be treated from childhood through adolescence — when the auditory pathways stop developing — and even later, although experts agree that early diagnosis and treatment is better. As with other learning challenges, a combination of professional, school, and home therapies is most effective.
Treatment includes a variety of exercises that target specific auditory deficits. Therapy can range from computer-assisted software programs like Fast ForWord and Earobics to one-on-one training with a speech and language therapist. If you choose to work with a professional therapist, here are some techniques commonly used:
- To overcome sound discrimination problem, the professional will train your child’s brain to differentiate sounds — first in a quiet environment, then with increasingly louder background noise.
- To sharpen auditory memory, an audiologist will use sequencing routines — having your child repeat a series of numbers and directions — to exercise the listening “muscles.”
- To manage language-processing problems, the therapist will train and encourage your child to ask a teacher, adult, or peer to repeat or rephrase an instruction or comment. The therapist and your child might also work on developing a customized note-taking system that enables him to capture the information being taught in the classroom.
Classroom accommodations for APD often include:
- Improving the acoustics — closing a window, shutting a door, adding a rug to help absorb sound — can help a child with APD “hear” the teacher.
- Seating your child in the front of the classroom, away from students who might be disruptive, will also enhance a child’s ability to listen.
- Asking a teacher to face your child, speak slowly, and use simple sentences when giving assignments can help him retain the information. Writing instructions on a blackboard or a piece of paper can reinforce what was said.
The following tips will increase your child’s ability to better listen at home:
- Don’t try to have a significant conversation when your child is in another room, watching television, or listening to music — or when an appliance is running.
- Before you start a conversation, be sure your child is ready to listen (finished with what she was doing). Also, face her directly and make sure she’s looking at you.
- Speak slowly and use simple, short sentences; pause between ideas.
- Encourage your child to ask you to repeat something that he doesn’t understand.