29 November 2017
New diagnostic tests for auditory processing disorder (APD), which is estimated to affect between 2 and 7 per cent of children could be available within five years through research funded by the charity Action on Hearing Loss.
APD, a hearing problem where the brain is unable to process sounds in the normal way, can affect people of all ages but often starts in childhood. People with APD appear to have normal hearing when assessed using a standard hearing test; despite this they have difficulties processing and making sense of sounds, including complicated and fast-changing sounds like speech.
APD can present lifelong difficulties when misdiagnosed, affecting skills like communication, learning and social skills and can be associated with children struggling at school.
The researchers involved hope that the new tests will give clinicians a clear diagnosis of APD at an early stage in a child’s development, in order to help parents and teachers to provide learning support swiftly so that they are not left behind at school or with their peers socially.
Action on Hearing Loss has funded the University College London (UCL)-led study to better understand the nature of this much misunderstood condition.
Professor Stuart Rosen, supervising Shiran Koifman at UCL, are developing an alternative approach to diagnose APD in children by focusing on their ability to understand speech when other sounds are present, sometimes in the same place, and sometimes in a different location. When someone is listening to a person talk and that person is close to a source of background noise, it makes it more difficult to understand what that person is saying. When the person talking and the source of background noise are further apart, the brain more easily recognises and separates them out and focuses on one while ignoring the other, meaning that it is much easier to understand what the person is saying. This is known as ‘spatial release from masking’ and is related to the brain’s ability to hear sounds in three dimensions.
Some children suspected of having APD seem to struggle with this kind of listening, finding it difficult to understand someone talking even when they are not close to a source of background noise. By being able to accurately measure a child’s ability to listen in this type of situation, it could help identify children with APD and better understand the difficulties they are facing at an early stage. The research team is also trying to understand the exact nature of the difficulties children can show in this task, and are developing a new test of attention, which they also hope will be useful to clinicians.
Dr Ralph Holme, Director of Research at charity Action on Hearing Loss says: ‘Diagnosing auditory processing disorder is difficult as there is no ‘gold standard’ test or set of criteria that can be definitively used at the moment, which means that many children are not identified and they often struggle at school. With Action on Hearing Loss funded research at UCL, we hope to develop tests able to diagnose children with APD, which will help parents, teachers and clinicians to support them by providing learning support so that they can thrive in school and everyday life.
‘Often children who haven’t been diagnosed with APD are labelled as having ‘behavioural issues’, but with early diagnosis, they can be given the tools needed to flourish and reduce the frustration that they experience, while giving relief to their parents. It can be extremely upsetting for a child with APD if they go undiagnosed, which is why research to better understand and diagnose this extremely misunderstood disorder is so important.’
Auditory processing difficulties can also affect older people who have no detectable hearing loss, because, as the brain ages, its ability to process sounds deteriorates.
Notes to editors
RNID is the national charity helping people living with deafness, tinnitus and hearing loss to live the life they choose. RNID enables them to take control of their lives and remove the barriers in their way, giving people support and care, developing technology and treatments, and campaigning for equality.
Auditory processing disorder (APD) is a hearing problem where the brain is unable to process sounds in the normal way. APD can affect people in many different ways. A child with APD may appear to have a hearing impairment, but this isn’t usually the case and testing often shows their hearing is normal.
The British Society of Audiology has a useful position statement on APD at: http://www.thebsa.org.uk/resources/apd-position-statement/
A case study of a 19 year-old University student who was only diagnosed with APD at the age of 14 is available upon request, alongside his parent, and Action on Hearing Loss spokespeople.
This project was funded through a donation from the Masonic Charitable Foundation.