The action of listening involves a complex interaction
between the peripheral and central auditory systems.
What is Central Auditory Processing?
Central Auditory Processing is about what the brain does with sound after it receives an auditory signal from the ear.
Central Auditory processes consist of the following:
Binaural processing
- Sound Localisation and Lateralization
- Auditory performance with competing acoustic signals and degraded acoustic signals.
Auditory discrimination – ability to discriminate between speech sounds in words and sounds that sound similar
Temporal processing – Temporal aspects of audition which include temporal resolution, temporal masking, temporal integration and temporal ordering (pattern recognition).
Auditory closure – ability to fill in and recognize an acoustic signal when parts of the signal are missing or modified.
Auditory figure ground – ability to understand speech in the presence of noise.
Dichotic Listening – ability to respond to competing signals directed to both ears simultaneously. Binaural integration – ability to identify and combine (integrate) two different messages presented to both ears (binaural) at the same time. and Binaural separation – ability to listen to a message presented to one ear while ignoring auditory competition coming into the opposite ear
Binaural interaction – ability to take incomplete information presented to each ear and fuse the information into an understandable message (binaural fusion)
What is Central Auditory Processing disorder (CAPD)?
CAPD is a general term for subtypes of disordered auditory processing in adults and children.
In CAPD, the ear hears the sounds but the brain cannot process the sound due to an alteration in one or more auditory processing abilities.
Individuals have normal hearing thresholds but do not hear well. The processing of sound is disordered in the pathways from the auditory nerve through the brain stem and higher auditory pathways in the brain.
What are the causes of Auditory processing disorder?
- Age-related changes in CANS function
- Genetic determinants
- Neurological disorder, disease, or damage
- Brain injury (e.g., head trauma, meningitis)
- Cerebrovascular disorder (e.g., stroke)
- Degenerative diseases (e.g., multiple sclerosis)
- Exposure to neurotoxins (e.g., heavy metals, organic solvents)
- Lesions of the central nervous system (CNS)
- Seizure disorders
- Neuromaturational delay secondary to deafness/auditory deprivation
- Otologic disorder, disease, or injury (e.g., auditory deprivation secondary to recurrent otitis media)
- Prenatal/neonatal factors
- Cytomegalovirus (CMV)
- Hyperbilirubinemia
- Low birth weight
- Prematurity
- Prenatal drug exposure
- Anoxia/hypoxia
Signs of Auditory processing disorder in children
- General – distracted and overwhelmed by background noise and competing noise, soft, rapid, or distorted speech, accented speech, speech in reverberant environments, and speech over the phone.
- Behaviour and attention improves in quiet environment, difficulty following classroom discussions. Prefer to have the television volume loud. Become frustrated with certain tasks. Trouble filling in missing auditory information.
- Speech and communication – difficulties following a set of instructions, mix up letters in words as they have difficulty hearing differences in sounds, mumbling and not using words, frequently asking for repetition.
- Delayed language development – due to language difficulties (confuse syllable sequences, problems developing vocabulary and understanding language
- Memory – poor attention when listening to verbal information, inability to process information and result in low quality work, poor engagement and what appears to be memory issues but is in fact inability to even properly process the information. Difficulty remembering spoken information, difficulties following directions. Difficulties expressing thoughts in an organised manner. Poor academic performance in the classroom.
- Reading and Writing– they will say letters that are not in the word, behind peers in reading grade levels, struggles to learn letters and sounds and therefore have poor reading fluency, poor handwriting.
- Spelling – words are not spelt phonetically, spellings are different each day as they cannot store the mental image of the word.
- Maths and sequence – poor mental maths, difficulty following maths rules, challenge to learn sequence of numbers, word problems in maths are difficult.
- Music – difficulty singing in tune and poor musical ability
Please contact us for more information on auditory processing disorder and to book an appointment for your child.
