Auditory Processing Disorder: Understanding the ABCs of APD

Auditory Processing Disorder (APD) is a disorder of the auditory (hearing) system which causes a disruption in the way an individual’s brain understands what they are hearing. This means that someone with APD does not have hearing loss, despite showing difficulty with hearing-related tasks. Auditory Processing Disorder, also referred to as Central Auditory Processing Disorder (CAPD), can occur in both children and adults, and can only be tested for and diagnosed by an audiologist.

APD is a disorder of the auditory system in an area of the brain called the auditory cortex. There are many signs and symptoms which vary by patient. Many of these symptoms can be associated with other commonly known disorders, such as ADD/ADHD, Autism Spectrum Disorder and speech or language disorders. A child with APD often appears to have a combination of many symptoms. Some of the most frequently reported symptoms include:

• Significant difficulty understanding speech, especially in the presence of background noise
• Difficulty following multi-step directions that are presented verbally, without visual cues
• Easily distracted by loud or spontaneous (sudden) sounds
• Difficulty with long periods of listening
• Difficulty remembering or summarizing information presented verbally
• Difficulty reading, spelling, or writing when compared to peers (performs consistently below grade level)
• Trouble following abstract thoughts or ideas
• Delayed or misunderstanding of jokes, idioms, and figurative language

APD is relatively rare – impacting only about three to four percent of the population – and is not always fully understood. Currently, APD is recognized as a “specific learning disability” under the Individuals with Disabilities Education Act (IDEA). This qualifies a student for reasonable services and accommodations at school if they have been diagnosed by an audiologist.

Following a diagnosis of APD, a customized list of recommendations is created by the audiologist and provided to the family and school for consideration. Each child and diagnosis is different, so careful attention is taken to ensure that individual needs are met appropriately.

Recommendations may include:

• Specific and strategic seating arrangements in class
• A device to help raise the level of the teacher’s voice above the classroom noise, called an FM system
• Written or picture-based instructions to accompany verbally presented instructions
• Specific focus on auditory processing skills in a therapy setting

Often, concerns about APD are identified by a parent or teacher. A referral to an audiologist for evaluation can then be placed by the child’s pediatrician. Once the referral is received, a team of audiologists carefully review information about the child to determine if requirements for testing are met. Due to the complexity of APD, there are several factors that are required for a child to be eligible for testing. A child must be at least seven years old, and have normal hearing, normal speech and language skills, and average (or at least near-average) intelligence. In addition, there are some additional conditions that prevent a child from qualifying for testing. 

Common reasons that a child may not be eligible for APD testing include:

• Autism Spectrum Disorder
• Down Syndrome
• Developmental delay or disorder
• Intellectual disability or below-average IQ
• Significant speech and language disorders, such as apraxia of speech, stuttering, etc.
• Hearing loss of any degree or type
• Less than seven years of age

Because of similarities between APD and other disorders, determining if a child is eligible for testing requires a thorough review of the child’s past medical, educational and developmental history. Testing for APD requires a child to participate in several, lengthy, listening tests that assess different areas of the auditory system which require a significant amount of attention and effort. The results of each test are reviewed to determine if a diagnosis of APD is appropriate.

The areas of the brain responsible for auditory processing abilities grow and develop until around age 13, when the auditory system is considered to be more mature and adult-like. Due to this, it is possible that a child who was diagnosed with APD before age 13 could essentially “grow out” of it. Additionally, a child’s auditory processing skills may also improve if he or she is receiving therapy for APD. For these reasons, it is recommended that children diagnosed with APD before age 13 be re-tested every 1-2 years to monitor for changes or improvements.