Sarah Millsap could hear just fine. But when her boss pulled her aside at a meeting last fall, she still worried that her ears could get her fired.
Why did she forget details and constantly ask for clarification? It was as if she couldn't understand plain English.
Millsap discovered she had auditory processing disorder (APD), a type of dyslexia of the ears. Although sounds reached her ears, they sometimes became scrambled on the way to her brain.
"There's a delay between what you say and what I hear," the 39-year-old woman said.
In the second or two it took her to process what she heard, she fell behind. Worse, she struggled to understand words in noisy environments and sometimes heard pauses that weren't there.
It wasn't a matter of intelligence.
"I'm in Mensa," Millsap said.
Although many people haven't heard of it, APD may affect as many as 1.5 million children in the United States, experts say, even more than are affected by autism. One expert in Kansas City -- audiologist Jack Katz, whom many consider "the father of auditory processing" -- says APD could be present in one in five people.
Since people with APD can usually pass ordinary hearing tests, the condition often is misdiagnosed or undiagnosed.
"These people need advocates," said Angela Loucks, a Lawrence, Kan., audiologist. "Children and adults are treated like they're less intelligent. ... But the good news is, we can make the processing better."
APD is diagnosed with a variety of tests that put stress on different parts of the auditory system in an effort to identify processing problems. Katz and Loucks use the "Buffalo battery," a series of tests that identify how patients hear in quiet and noise, how the ears work together, and how a person blends sounds to form words.
But not everyone's a believer.
Certain speech and hearing professionals, including some at the University of Kansas Medical Center, have problems with both the diagnosis and treatment of APD. Too often, they say, imprecise data can be wrongly interpreted. They also worry about the lack of scientifically standardized treatments.
John Ferraro, an audiologist and chairman of the department of hearing and speech at the University of Kansas Medical Center, explained the skepticism.
"(It) stems from the fact that we have yet to develop a diagnostic procedure that is well-accepted by the scientific community that's applicable to all who might have such a disorder," he said. "Therefore, you have to interpret the diagnosis."
In other words, it's hard to say for certain that a child has APD instead of, or in addition to, language impairment, attention deficit disorder or other problems.
"Yes, the numbers could be enormous," Ferraro said. "But the numbers are imprecise and based on tests that have not been scientifically validated."
Another problem: Even if you correctly diagnose APD, there are different treatments.
"And (they have) yet to undergo the rigors of scientific scrutiny," he said.
Still, he knows that treatments, such as the ones given by Katz, Loucks and others, have helped many people.
"If this were my kid, and something like this helped him or her, I'd love it," he said.
Comedian Rosie O'Donnell, who wrote the foreword to "The Sound of Hope: Recognizing, Coping With and Treating Your Child's Auditory Processing Disorder" by Lois Kam Heymann, has a son with APD.
The boy, Blake, was happy but became frustrated in elementary school understanding and making himself understood. Some asked whether he was deaf.
"He said, 'I'm so dumb I can't do my lessons' O'Donnell said in an interview with The Kansas City Star from her home in Nyack, N.Y. "And I said, 'You're not dumb, honey.'
"It just breaks your heart."
After treatment, her son "blossomed," O'Donnell said. "He was in the raging rapids, and we pulled him to shore."
Millsap also got help. After Loucks worked with her, she no longer worries about getting fired.
Still, there are frustrations. Recently she failed a weekend course despite scoring high on a test. The teacher said she asked too many questions, rewrote her notes and was too much of a "perfectionist."
Millsap told the teacher about her APD, even producing a letter from Loucks.
"I know what auditory processing disorder is," the teacher reportedly said. She then gave an example of a child who has "selective hearing," meaning the child chooses what they want to hear and tunes out the rest.
"That's one of the biggest misconceptions there is," Millsap said. "Even when you're dealing with educators, they still don't get it."
Experts say the disorder can cause problems ranging from poor performance in school and the breakup of marriages to excessive shyness and bullying. One study even found the disorder present in higher concentrations in prison inmates than in the general population.
Although there is isn't a cure, special exercises can help build auditory pathways. Katz and Loucks say they can make significant progress in 10 to 15 weeks. An evaluation costs $350, and each session is $90.
Katz and Loucks do not take insurance, but say some patients have successfully submitted bills for reimbursement.
APD manifests itself in a variety of ways, Loucks said.
"In men it could be anger, and with women they could act like they're a 'dumb blonde.' In children, they might start developing language later."
Lisa Wright Murray of Lee's Summit, Mo., started noticing problems with her 9-year-old son, Jonah, in second grade.
"You could ask him a question," she said, "and he would stare at you like you were speaking a foreign language."
Murray said tests found that Jonah had "perfect hearing."
Then she took him to Katz and Loucks, who found that Jonah had difficulty decoding sounds in noisy environments. He also had trouble differentiating words such as "Kenyan" and "canyon." Loucks used phonetic exercises to help Jonah's ears work better together.
Now he's more engaged in conversations, and is reading above his grade level.
"He actually has a clever sense of humor we didn't know about before," Murray said. "Angela has been a godsend."
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