Lecture 13 Central Auditory Processing Disorder

Nomenclature

• Name of disorder is not universal.

• Professional organization commonly refer to disorder as:

  • Central Auditory Processing Disorder (CAPD)

  • Auditory Processing Disorder (APD)

  • Auditory Processing (AP)

CAPD as defined by ASHA (2005)

“central auditory processing (CAPD) refers to the efficiency and effectiveness by which the central nervous system (CNS) utilizes auditory information....(CAPD) refers to the difficulties in the perceptual processing of auditory information in the central nervous system and the neurobiological activity that underlies that processing and give rise to the electrophysiologic auditory potentials...CAPD may co-exist with other disorders (e.g., attention- deficit/hyperactivity disorder (ADHD), language impairment, and learning)...”

CAPD simply defined

• Deficit with the neural processing of auditory information in the central auditory nervous system (CANS) which is not caused by peripheral hearing loss, higher-order language deficits, or cognitive deficits.

• "Auditory processing is what the brain does with what the ears hear." - Jack Katz, Ph.D., CCC-A/SLP

Prevalence of CAPD

• Difficult to answer due differences between test batteries and criteria.

• Studies have shown very different results in the prevalence of CAPD

  • Likely due to no “gold standard” test battery

    • Disagreement in criteria

• There is a tremendous need for further CAPD research

• CAPD affects both children and adults

Symptoms of CAPD Examples (ASHA)

• difficulty localizing sound

• difficulty understanding spoken language in competing messages, in noisy backgrounds, in reverberant environments, or when presented rapidly

• longer response time during oral communication

• frequent requests for repetitions

• inconsistent or inappropriate responses during oral communication

• difficulty comprehending rapid speech

• difficulty following complex auditory directions

• difficulty learning songs or nursery rhymes

• misunderstanding messages (e.g., difficulty detecting prosody changes that help to interpret sarcasm or jokes)

• poor musical and singing skills

• difficulty paying attention or avoiding distractions

• reading, spelling, and/or learning problems

Symptoms of CAPD (ASHA)

• No one behavior exclusively represents CAPD

• Differential diagnosis can be difficult

  • CAPD vs

    • ASD?

    • AD/HD?

    • Language deficit?

Possible Scenario (Case History)

• Patient presents with significant concerns and complaints about their ability to understand friends and family.

• Family reports patient seems hard of hearing or does not pay attention.

• Patient reports difficulty localizing the source of sounds.

Possible Scenario (Test Results)

• Normal otoscopy and tympanogram

• Normal otoacoustic emissions

• Normal pure tone thresholds

• Normal SRT and WRS

Who can be tested for CAPD?

• Traditionally, testing was not administered until a child was at least seven years old

• Concerns with increased inconsistently and weaker reliability

• Limited availability of normative data

• Some tests have started to be completed by children younger than seven

• AAA (2010) discusses using a limited test battery with tests designed for young children to identify those “at-risk”.

• Those children identified would be monitored closely, provided with enrichment activities, and tested for a definitive diagnosis as early as possible

• Even if a child is too young for CAPD testing, they should be referred for hearing evaluation

Role of SLPs

SLPs are part of interdisciplinary team playing a role in the identification, screening, assessment, and treatment.

• Educate other professionals about the needs of individuals with CAPD and the role of SLPs in CAPD treatment.

• Screen auditory processing skills in individuals identified as at risk for CAPD and determine if a referral for a diagnostic CAPD evaluation is warranted.

• Conduct a comprehensive and culturally and linguistically responsive evaluation of speech, language, cognitive, social, and communication skills.

• Identify or differentiate disorders in phonology or language processing that may co-occur with CAPD.

• Provide education and counseling to the patient and their family

Role of Audiologists

Assessment of CAPD

CAPD Test Battery

CAPD Treatment

Auditory Training

Why Teamwork is Important