Auditory Processing Disorder
Feeling my ears after attending a rather loud, though thoroughly enjoyable concert, lead me to contemplate those children I have recently seen with auditory processing disorder (APD). It gave me pause for thought about what it may be like for those with APD, as the next day I struggled to hear clearly. But for me it was only temporary.
What is APD?
While a child can hear the sounds, the difficulty lies with the ability to process that information in the brain. It is a persistent limitation, unlike my temporary struggle, and has consequences for participation within our society.
How common is it?
In New Zealand it has been estimated at 6.2% in a review undertaken by the University of Auckland in 2014(1).
How does it present?
Children with APD may have poor focus, reduced attention span or academic challenges. Though they can hear noises, understanding is not a given, prompting frequent requests to repeat information, or simply ignoring what is being said to them. Following instructions is difficult, they may seem to be oppositional, and behavioural consequences are not unusual.
How is it diagnosed?
A carefully trained audiologist will undertake a battery of tests, but this condition is not reliably diagnosed until the age of 7. This is the age where the robust data around normal values exist. In some cases, children can be assessed at a younger age, but usually the diagnosis is provisional, with a plan for more formal review when they are older.
As there are overlapping conditions with similar symptoms such as ADHD, ASD, Specific Learning Disorders, etc thought should be given to investigating these.
What are the causes?
The literature reports many, but I would suspect that we don’t really know. There is a higher association of the condition in those who have had repeated episodes of otitis media, but not all with ear infections will develop this. It is also seen in a post-traumatic situation, or related to concussion, this mechanism brings about a sudden onset of symptoms rather than the gradual onset usually seen. Like all conditions there is a hereditary component whether that be genetic or environmental, and some children seem to have a maturational delay where they grow out of this.
I wonder about the sound that our children are subject to from an early age with television, devices, ear plugs and earphones. It all begins early now with the use of white noise to get babies to sleep. So, in my view we should be vigilant about what sounds exposure our children are subject to.
How is it treated?
Hearing devices can be useful for some children with APD. There are other strategies such as hearing training, listening, speech language, school support and software packages that can help. In most cases more than one approach is needed (multi-disciplinary). Right now, the many promoted approaches for auditory integrative training techniques have not met scientific standards for efficacy. However, as more is learnt about the brain, it’s ability to change or rewire (neuroplasticity), this is an area to watch.
Summary
APD is an emerging condition with improved understanding and research that is coming out all the time. There is overlap in the presenting symptoms of this condition with many others that may be more familiar, so an open mind to more than one diagnosis is prudent. The Europeans have developed an infographic below (2), which clearly shows that hearing is more than we currently test for.
In my view, APD is something to consider alongside many behavioural or learning presentations. It may not be easy to sort out, but as there is a different management strategy for APD, compared with other conditions and I think it is well worth investigating.
References:
- https://www.health.govt.nz/system/files/documents/publications/auditory_processing_disorder.pdf
- Front Neurol. 2019; 10: 1096. Clinical Expertise Is Core to an Evidence-Based Approach to Auditory Processing Disorder: A Reply to Neijenhuis et al. 2019. Vasiliki Iliadou,1 Christiane Kiese-Himmel,2,* Doris-Eva Bamiou,3 Helen Grech,4 Martin Ptok,5 Gail D. Chermak,6 Hung Thai-Van,7 Tone Stokkereit Mattsson,8 and Frank E. Musiek9