Henry is fidgety and distractible during classroom activities, according to his second grade teacher.
During gym class, he's hypersensitive. He gets cranky and lashes out at classmates who "are yelling at me and telling me what to do."
His mother has noticed similar behaviors at home. When he's doing homework, she says, "He uses every little sound as an excuse to delay getting down to work." Even the dishwasher distracts him, despite the fact that the kitchen is on the other side of the house. "He just can't sit still."
This sounds like a classic attention deficit disorder (ADD ADHD) profile, right? Well, yes and no. Henry does have ADHD, but an audiologist has also diagnosed him with something called auditory processing disorder (APD).
Do you hear what they hear?
While APD isn't as well known as ADHD, it is becoming increasingly common. Roughly 7 percent of children have some type of auditory processing difficulty.
But what is it exactly? At its most general, APD is a glitch in the brain's ability to filter and process sounds and words. An APD child doesn't have difficulty hearing — in fact, in most cases, her hearing is good. Rather, her brain perceives the sounds incorrectly, affecting the child's ability to distinguish between similar sounds (da and ga, for example).
Some children with APD also have trouble screening out background noise, so they pick up bits of surrounding sounds. The echo in a gymnasium or the hum of the air conditioner in the classroom interferes with the conversation at hand. It's like listening to the radio with interference from other stations 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. Combine APD with ADHD, and a child's abilities to listen and remember are severely compromised.
Sorting out symptoms
Just as APD can affect a child's ability to focus, so an attention deficit can affect auditory processing. Symptoms of the two disorders often overlap. Studies suggest that 50 percent of those diagnosed with ADHD may also have APD. Experts continue to disagree whether APD is a manifestation of ADHD, or if they are separate disorders.
How can a parent tell if his or her ADHD child has APD? In general, children with ADHD exhibit inattention, distractibility, and hyperactivity in any environment. Children with APD, on the other hand, usually don't have difficulty focusing and paying attention in a quiet space. But many children with APD are exquisitely sensitive to sound. In fact, some sounds can "hurt" — a blender, a train engine, police sirens. My daughter, who has APD, plugs her ears before the movie previews, in case the sound gets loud.
"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.
A study conducted at the State University of New York in Fredonia looked at the effects of Ritalin on auditory processing in children with both ADHD and APD. The drug didn't improve auditory processing, despite improving children's performances on a standard test that measured attention and impulsivity.
Do you think your child's poor performance in school and his social awkwardness may be caused or exacerbated by APD? Here are the facts to help you determine whether this is the case and which treatments may help.
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 10 to 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, low birth weight, 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 responsive to early intervention.
Three disorders in one
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 child 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, children with faulty sound discrimination will run words together and drop word endings and unemphasized 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.