Central Auditory Processing Disorder, or CAPD (also sometimes referred to as Auditory Processing Disorder, or APD), is a complex hearing disorder based not on the ears’ inability to hear sounds, but on the brain’s inability to process and interpret them correctly. With CAPD, your ears have no problem hearing sounds (especially the sounds associated with speech) properly, but something is affecting the brain’s ability to interpret these sounds. That’s why the disorder is sometimes summarized as an ear-brain coordination problem.
CAPD affects as many as 2% to 5% of school-age children, and as many as half of the children are diagnosed as having a learning disability. One of the characteristics of Central Auditory Processing Disorder is that children who have it have difficulties recognizing subtle differences between the sounds of similar words, even though they have no problem hearing the words. The problem is worsened with background noise and in some cases of CAPD the child can hear well in quite environments and only has difficulty in noisy environments.
CAPD is often difficult to detect, because when children’s hearing is tested in a quiet room, they can clearly hear the pure tones they hear through the testing equipment, and they similarly have no apparent problems hearing and interpreting speech in non-noisy environments. As a result, their audiogram results may appear normal, but they may nevertheless have difficulties distinguishing similar words, locating where sounds are coming from, recognizing repetitive patterns in high and low sounds, or hearing more than one person’s voice at a time.
The symptoms of CAPD also tend to appear in other areas of life, as the child struggles to deal with not being able to understand people speaking to them or around them. The disorder may manifest itself in a difficulty following instructions, being easily distracted by loud noises, appearing forgetful or disorganized, or slow to develop reading, spelling and language skills. When given standard hearing tests, these children appear to have normal hearing, so these symptoms are often confused with or mistaken for signs of other problems such as depression or Attention Deficit Hyperactivity Disorder (ADHD). This misdiagnosis is further complicated by the fact that a child may in fact have ADHD or some other learning disorder and also have CAPD.
Early detection of CAPD is critical, because to ensure the child’s proper social and educational development, the sooner the problems are diagnosed, the sooner they can be treated. A standard hearing test doesn’t rule out CAPD. If you detect any of these signs in your children, schedule a professional hearing test that can replicate the conditions where the child struggles.