Educational hearing tests & auditory processing
Although we hear with our ears, it is our brain that makes sense of the information we hear. The mechanism by which the brain analyses and assigns meaning to auditory information is known as auditory processing. A Central Auditory Processing Disorder (CAPD, sometimes called APD) occurs when this process is impaired.
What is the effect of a CAPD?
Efficient processing of auditory information is very important for children and adults to be successful in learning and communication. A CAPD will have an impact on educational achievement, social development, relationships and general emotional well being.
Listed below are some common behavioural characteristics of people with a CAPD. Central auditory processing consists of a number of different underlying mechanisms. The actual symptoms of a person's CAPD will depend on which mechanisms are affected.
- Difficulties hearing in noise.
- Frequent requests for repetition.
- Inability to follow instructions.
- Poor memory for auditory information.
- Difficulties identifying features of speech sounds so that reading is affected.
- Academic problems, especially reading, spelling and comprehension.
- Behavioural problems.
- Short attention span.
- Social difficulties.
(It is important to note that these symptoms can result from other disorders. Careful assessment is required to identify the underlying cause).
When should a CAPD assessment be carried out?
A CAP assessment is recommended for children and adults with:
- attention, listening, learning and reading/spelling problems,
- a history of regular middle ear infections where a fluctuating hearing loss may cause a delay in the development of the central auditory pathway.
- CAPD associated conditions such as dyslexia or other learning disorders and ADD/ADHD.
CAPD Testing is suitable for adults and children from age 7. Before age 7, there is too wide a range of auditory processing abilities to make reliable comparisons.
Assessment of CAPD
Central auditory processing is an umbrella term for a number of different underlying mechanisms. At our clinic, a comprehensive test battery is used to assess these mechanisms. The specific processes assessed are:
- Dichotic listening: This refers to the processing of information received in both ears when the information to each ear is different. It is important for hearing in noise.
- Temporal processing: This is the ability to process time-related cues in sounds which are critical for speech and music perception.
- Spatial processing: This is the ability to use cues from the location of sounds (spatial cues) to separate the target message from background noise.
- The ability to understand distorted speech: Distorted speech has fewer cues to facilitate a person's ability to guess a message they have not heard clearly. A person with CAPD, with a less efficient auditory system, will struggle more with this task.
- Auditory memory: An efficient auditory memory system is required for effective processing, storing and recalling of auditory information.
The tests we use have been selected to identify weaknesses or problems in each of these areas.
CAPD testing is relatively demanding, and parents are advised to arrange morning appointments when their children are most alert. Although most children with CAPD have normal hearing, a standard hearing test must be carried out to exclude the possibility of a peripheral hearing impairment. This part of the assessment is carried out at the first appointment. The complete assessment takes up to 2 ½ hours, which is spread over two to three appointments. A detailed report discussing the questionnaire responses, test results and rehabilitative recommendations, is provided.
Management of CAPD
A comprehensive management program can be put together, once a person's specific auditory processing weaknesses have been identified. This program will also take into account other factors such as the age of the person and their particular requirements. The aim of the rehabilitative program is to both strengthen a person's auditory processing skills as well as to teach them strategies to better manage the auditory processing problems they are having. The management program for CAPD will usually consist of a combination of the following four components:
1. Modifications to the person's classroom and home environment. The goal of this step is to improve the person's access to auditory information by minimising the amount of energy required for them to obtain this information.
2. Teaching the person to be responsible for their listening comprehension, so that they are able to put in place strategies for determining and retaining the content and meaning of each message.
3. Targeting each individual auditory processing deficit as identified by the assessment. The goal of this stage is to stimulate the specific part of the auditory system in order to facilitate improvement. This is done through therapeutic activities. Depending on the type of exercises, some may be done at home, within our audiology clinic or with a speech pathologist. There are also computer programs available for specific auditory processing deficits.
4. Use of an FM unit, which allows a teacher's voice to be transmitted directly to the child's ears. This overcomes the loss of volume and clarity of the teacher's voice due to distance, background noise and poor classroom acoustics.