Neurodivergence and Sound: The Implications of Central Auditory Processing Disorder 

The gifted in sound, the incredible talents whose music can touch our hearts and souls, who can identify a bird by its song, and so much more, also have sound sensitivity. What I’m going to write about here is how those highly sensitive to sound can also have Central Auditory Processing Disorder, (CAPD), why it is important to understand its implications for the neurodivergent, a little history as to why we don’t know what we should about it, and what can be done about it.  

CAPD. What is it?

CAPD can be caused by high sound sensitivity in the ear – a really precise and good instrument, perhaps designed, and evolved for earlier human times when we were surrounded by less noise. The child (or baby) with a highly sensitive ear can become overwhelmed by sound. In between the ear and the brain is where sound is received is the brain’s white matter and is where sounds are sorted and sifted over time as the child grows, deciding what is more important, and what to filter out, in order to protect the brain. The white matter in a highly sensitive child scrambles or tries to muffle the sound before it reaches the brain and overwhelms the individual. This becomes the way the white matter of the brain then “learns” which sounds to give more importance to. It may even block some pitches of sound altogether before it can have access to the brain. Eventually, the regular pathways have been diverted so much that the sound reaching the brain has not learned correctly what to take in and what not to, so that the airplane flying overhead has the same level of importance as mom’s voice: the filter has gone haywire. 

What can be done about it? 

Make sure to go to a proper audiologist. Some children with highly sensitive hearing who get tested for hearing by a typical audiologist come out with good or even better-than-average hearing results, because they have a good hearing instrument. But when you look further at how their brain is processing the sound, we can find out what needs to be redirected. This can be diagnosed and addressed by knowledgeable auditory specialists. These professionals will check and recheck weekly to make sure the auditory therapy is being received accurately. (See more info in “history,” below.)

What are some signs of CAPD?

Signs of CAPD can be as follows: a child appears to not hear you when you are talking to them from behind (because they can not see your lips move, or have some sign they are being addressed,) they make loud noises at random times (trying to get feedback from the brain that they are missing,) they are very sensitive to noise, so that they are agitated by the sound of traffic, etc., and louder noises can send them over the edge. The child who can focus in small groups, but goes berserk on the playground. The sensory child who can navigate their way up a flight of stairs, but not when there is background noise. They can be behind in reading, and even talking. Most end up in speech therapy. (We can only make the sounds we hear correctly.) 

There is more to know about CAPD, but I give you my explanation here because, as you can see, it is one of (many) ways that neurodivergent learners can be misunderstood. 

CAPD alone can cause misunderstandings about a student’s ability to pay attention (and can co-occur with ADHD), read, comprehend, prove their cognitive potential, and can even impact balance – like the student who can not use the stairs at school when it is loud, but otherwise can give it a shot. This is hyperacusis, – the body is so thrown off by what it hears a very loud sound, that it’s balance is also thrown off. This child probably also has vestibular issues, and correcting hearing can help. My point is that, as in most neurodivergent traits, CAPD is invisible and because of this there are more implications that we need to be aware of. It also complicates the proper diagnosis of other neurodivergent traits. 

Why isn’t this common knowledge? What is the history of addressing CAPD? 

So why aren’t we addressing CAPD? These same audiologists have reported to me that years ago, addressing CAPD claimed to “cure autism.” Parents flocked to get their children treated, and not only did they find it didn’t cure autism (I think we’ve moved on from this ideology by now.,) but that for many, the therapy caused intense anxiety in the children treated for CAPD. Obviously, this is not an outcome any of us want. I have since found that this can occur in some children, perhaps especially the highly sensitive ones. This treatment can raise a child’s anxiety to extreme levels. It is important to interview your audiologist before treatment to discern if they have knowledge of this phenomenon and how to address it, should the heightened anxiety occur. Yes, anxiety is often a mental health issue, but there are instances where sensory processing issues are the primary cause. The treatment for the anxiety is going to involve the integration and balance of the new hearing ability with other sensory systems in the body. This would be an OT (occupational therapist) or professional administering the auditory therapy. If they don’t know what you are talking about, don’t start the therapy with them. Some may have witnessed this, but didn’t know the auditory therapy was the cause. The field is still learning…. 

Lastly, do not assume that when you use the term auditory processing disorder or CAPD, that everyone is on the same page as to what it means. The range of understanding varies from not-at-all to “It’s probably made-up” to just sound sensitivity. “No, he yells a lot, he does not have auditory processing disorder,” is something I have heard. This is all understandable. Understanding and addressing CAPD in the way I describe here went into hiding, for lack of better words,  years ago due to the reasons I state above. But ignoring it is leading to what I consider one of the great invisible disabilities that the neurodivergent population must navigate. And as we all know, when anything is invisible, it can lead to further misunderstanding. 

Impact on Educational and Mental Health Assessments in those with CAPD.

Educational and cognitive testing for neurodivergent individuals is something I write and speak about often. If we are giving any kind of educational or psychological testing to a CAPD child, and do not understand the implications of CAPD on the outcome of the test, there is going to be an incorrect test. Full stop. I have asked several school psychologists and professional psychologists who perform neuropsychological and educational testing, and I have never heard one tell me they understand CAPD and how they would modify their tests if they did know. There are some, however, who know when to recommend an auditory assessment, but their test results still stand. The child and parent are then given an IQ score or told where their cognitive “deficits” lay based on the ability of a typical hearing child. 

As an extreme comparison, we would not have tested Hellen Keller’s cognitive abilities before she learned how to communicate, would we? 

There are many other ways that neurodivergent individual traits are important to understand when teaching, assessing and parenting them. CAPD is one of the few that can be addressed. This is just one of the very many reasons we need to understand not just CAPD, but the specific traits that make up our neurodivergent learners. Stay tuned…

©Teresa Currivan 2023