What is Auditory Processing Disorder?

Auditory Processing Disorder (APD) is a neurological disorder that affects how the brain processes auditory information. Individuals with APD often struggle to understand and interpret sounds, particularly in complex or noisy environments. This can lead to difficulties in following instructions, comprehending spoken language, and participating in conversations.

On a standard hearing aid evaluation, someone with APD will have normal test results despite their reported inability to hear well. This is because a standard hearing test only evaluates the ear canal, middle ear space and cochlea. But this is just the start of the auditory system!

Once the sound has made it to the auditory nerve, it travels through the brain for processing. The central auditory system is a very complex system that preserves, refines, analyzes, modifies, organizes, and interprets information from the ears. If this system is not working properly it can result in difficulty interpreting sounds in complex auditory input, such as rapid speech, speech in noise, and long bouts of speech.

Audtiory Processing

The 4 Types of Auditory Processing Disorder

Decoding
These individuals have difficulty quickly and accurately digesting and organizing auditory information. They may struggle with understanding complex or rapidly presented auditory information, making it difficult to follow conversations or process information in noisy environments. Recognizing subtle differences in phonemes is a common challenge for those with a decoding deficit.
Tolerance Fading Memory (TFM)
Individuals with TFM struggle with auditory memory and the ability to retain and recall auditory information over time. They may have difficulty remembering and following multi-step instructions or retaining verbal information for later use. This is especially true in the presence of background noise.
Organization
These individuals have difficulty in organizing and producing verbal output. They also tend to struggle with following oral instructions in the order they are given. Expressive language skills, including formulating coherent and organized responses to questions or expressing their thoughts verbally can also present challenges. Organization deficits typically occur with decoding and/or TFM deficits.
Integration
Individuals with an Integration deficit tend to have difficulty performing auditory tasks with other tasks since they cannot easily bring information together across multiple modalities and processing centers. For example, one challenge may include coordinating movements with auditory cues such as dancing or playing a musical instrument.

How common is APD?

Some studies suggest that APD affects around 2-7% of school-aged children. However, other research indicates higher rates, with prevalence estimates ranging from 5% to as high as 20% in certain populations.

In adults over 55, the prevalence of APD is estimated to be 23-76%.

APD also affects men more than women at a ratio of 2:1.

What causes APD??

The etiology of APD may be linked to a specific lesion or disorder, or may be unknown. Causes and risk factors for APD may include the following:

Genetics
Neurological disorder, damage, injury
Prenatal/neonatal factors
Otologic disorder, disease, or injury
Age-related changes in the central auditory system
Neuromaturational delay secondary to auditory deprivation

Signs and Symptoms of Auditory Processing Disorder

  • Difficulty localizing or pinpointing the source of sounds.
  • Problems with phonemic awareness and speech sound discrimination.
  • Mishearing or misinterpreting spoken language, leading to frequent misunderstandings.
  • Fatigue easily when listening.
  • Easily distracted by sounds.
  • Difficulty understanding speech in noise.
  • Difficulty understanding speech when multiple people are talking.
  • Struggles with processing and comprehending rapid speech or conversations.
  • Trouble following and/or remembering verbal instructions, especially those involving multiple steps.
  • Attention difficulties.
  • Challenges with remembering or recalling information presented orally.
  • Trouble with reading, spelling, and language-related tasks.
  • Poorer academic performance in language than in math/science.
  • Issues with organization and sequencing of auditory information.

Comorbidities of Auditory Processing Disorder

APD can sometimes coexist with other conditions or comorbidities such as:

1. Language Disorders: such as dyslexia or expressive/receptive language disorders.

Dyslexia
  1. Difficulty manipulating language either verbally and/or when reading and spelling
  2. Difficulty with phonological processing
  3. Fatigue easily when reading
  4. Difficulty processing what they read
  5. Difficulty following written directions
  6. May spell words phonetically but far from being correct (i.e., frens/friends)
VS
APD
  1. Difficulty processing sound
  2. Difficulty recognizing subtle differences in sounds (i.e short -i- vs short -e-)
  3. Fatigue easily when listening
  4. Need more time to process information heard
  5. Poor listening skills
  6. Academic difficulties especially in language
  7. Difficulty following directions orally
  8. Spelling errors tend to be omissions or the wrong sound (i.e blump/blunt)

2. Attention-Deficit/Hyperactivity Disorder (ADHD): There is a higher prevalence of APD among children with ADHD, and vice versa. It is also possible for a child with APD to be misdiagnosed with ADHD because their inability to understand what is being said can be seen as inattentiveness.

ADHD
  1. Inattentive
  2. Distracted
  3. Hyperactive
  4. Fidgety/restless
  5. Hasty/impulsive
  6. Interrupts/intrudes
VS
APD
  1. Difficulty hearing in background noise leading to perception of inattentiveness
  2. Difficulty following oral directions leading to perception of inattentiveness/distracted
  3. Poor listening skills
  4. Academic difficulties especially in language
  5. Poor auditory association skills
  6. Distracted
  7. Inattentive

3. Autism Spectrum Disorder (ASD): Sensory processing issues, including auditory processing difficulties, are often observed in individuals on the autism spectrum.

4. Developmental Coordination Disorder (DCD): Conditions such as dyspraxia.

5. Speech Sound Disorders: Conditions such as difficulties with articulation or phonological processing, leading to speech sound disorders.

6. Learning Disabilities: Such as difficulties with reading, writing, or math.

7. Sensory Processing Disorder (SPD): Conditions such as difficulties in processing and integrating sensory information, including auditory input.

While APD can co-occur with other conditions, not every individual with APD will have comorbidities, and the presence of comorbidities can differ between individuals. Each case is unique, requiring a thorough evaluation by professionals like audiologists, speech-language pathologists, or psychologists to accurately assess and diagnose these conditions.

Scheduling a APD Evaluation

APD Evaluations are completed Wednesday and Friday morning at Golden Ears Audiology Lakeway. Appointments are scheduled for 90 minutes and include a comprehensive hearing evaluation followed by processing testing in the sound booth. Following the evaluation, preliminary results will be given to the patient and/or their parents. A more formal review of results will be completed via a 30 minute phone call or video call with the audiologist the following week.

Schedule Appointment

Cost of Services

This will be an out-of-pocket cost of the patient. The full 2 hours of testing and review of results is $1200.

Treatment Options

Treatment for Auditory Processing Disorder may include auditory training, speech therapy, use of hearing aids or assistive listening devices to improve sound clarity, and educational support like visual aids.