Why the APD Label Still Matters, Even if the Tests Aren’t Perfect

Auditory Processing Disorder (APD) is under fire right now. A widely circulated article published just days ago by The Informed SLP questions the validity of APD as a diagnosis and casts doubt on how it’s tested and treated—particularly from the perspective of speech-language pathology.

This article is my direct response. I’ve been in the field of audiology for over 25 years, and for the past seven, I’ve focused almost exclusively on auditory processing, working with hundreds of families across the country and internationally. I am also a pioneer of the programming and applications of the low-gain hearing aid (LGHA) model for APD—a non-invasive, science-based intervention that has changed the lives of many children with subtle but significant listening challenges.

As someone who works with these children every day, I want parents, educators, and fellow professionals to understand that APD is real, it’s physiological, and it cannot be dismissed as attention, language delay, or behavior.

This isn’t just a clinical debate—it’s about whether children get the help they need, or whether we keep blaming them for missing a signal they never heard clearly in the first place.

If you work with or care for kids who “hear fine” but still struggle to understand, this is for you.

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Why the APD Label Still Matters, Even if the Tests Aren’t Perfect

By Dr. Rae Stout

Doctor of Audiology

A new article from The Informed SLP is making the rounds this week. It’s titled “Do You Hear What I Hear? Navigating Controversies in Auditory Processing” and offers a thoughtful critique of how auditory processing disorder is currently identified and treated.

I agree with many of their points. APD testing needs to improve, and bottom-up interventions alone are not enough. But I want to clarify a few things from the perspective of someone who works with these children every single day.

Auditory processing disorder is real. The current tests are imperfect, but that does not mean the disorder does not exist. We would never say dysgraphia or sensory processing disorder are not real just because they are hard to quantify. APD is like that. It is a sensory access issue that affects language, learning, and behavior. If anything, we need more nuanced testing, not less attention.

Let’s be clear. APD is not an attention problem. It is not a behavioral disorder. And while it may affect speech and language, it is not caused by them and should not be diagnosed as such. The problem is that many professionals outside of audiology are treating it backwards. You cannot treat an upstream disorder by working downstream. You cannot treat a cause by treating the symptoms. That defies both logic and clinical experience. If the root issue is sensory, then the intervention has to start with sensory access. Otherwise, we’re chasing symptoms and calling it support.

We are also beginning to explore how physiological testing might support our understanding of listening effort in children with APD. While most current evaluations are behavioral, there are ways to make them more robust. We already have access to subjective listening effort measures and dual-task paradigms. These can be integrated now, though few clinicians are doing so consistently.

In the research setting, tools like pupillometry, heart rate variability, galvanic skin response, and surface muscle activity above the ear, such as contraction of the superior auricular muscles, are showing promise. Late latency auditory evoked potentials are also being studied as objective markers of auditory effort. But most of these tools remain expensive, experimental, or limited to laboratory environments. They are not yet accessible for everyday use.

It’s worth asking why APD is held to a different standard. When I say APD is a physiological condition, I don’t mean that we can always point to a single brain lesion on a scan. Especially in children, the breakdown is more often developmental and due to inconsistent access rather than localized trauma. But that does not make it behavioral. It means the problem lies in the way the brain processes sound—a sensory-level function—even if the markers aren’t yet visible in conventional imaging or neurodiagnostics. We do not require brain imaging to diagnose ADHD, dyslexia, or mixed receptive-expressive language disorder. These are all diagnosed behaviorally. And the tools used in those fields are not more precise than ours. They are just more accepted.

In Australia, spatial hearing tests like the LiSN-S are more commonly used and validated. But they are often not integrated with the broader battery used in the United States. On the flip side, many US-based tests ignore spatial processing altogether. What we really need is a blended, interdisciplinary approach that includes both behavioral and physiological data, drawn from the best tools each region has to offer.

Yes, attention can influence how someone performs on a test. A distracted child may miss more items or seem inconsistent. But that does not mean attention is the root of the problem. We do not call asthma a motivation problem just because kids run slower when they are wheezing.

In fact, the relationship goes both ways. Poor auditory clarity can look like inattention. Kids with APD often zone out or fidget or seem oppositional because they are constantly straining to decode unclear or incomplete input. That effort creates listening fatigue. It is not a choice. It is not laziness. It is what happens when the brain has to work too hard for too little return.

Stimulant medication may help children with ADHD sustain attention longer, and sometimes that means better performance on auditory tasks. But research shows those effects do not carry over to actual auditory processing. The medication supports alertness. It does not change how the brain processes sound.

When Tillery and colleagues tested children with both attention and auditory difficulties, they saw improvement on attention tasks but not on auditory processing scores. The medication helped the child focus. It did not fix the signal.

If APD were just ADHD, Ritalin would solve it. It doesn’t. What actually helps are bottom-up interventions that improve the signal itself. That includes auditory training, remote microphone systems, low-gain hearing aids (a type of subtle amplification that typically increases volume by about 10 dB, just enough to enhance speech clarity without amplifying background noise), and phonological support that makes language more accessible.

Auditory training in particular can help rebuild timing, discrimination, and closure abilities. I primarily use generalized, integrated activities for auditory training—like following multi-step directions in a noisy environment, identifying filtered or altered speech during story-based tasks, or tracking lyrics while singing along to music with adjusted background volume. These activities support attention, auditory closure, and speech-in-noise processing in natural contexts. I occasionally supplement with structured computerized programs to reinforce specific skills. I also use tools like Acoustic Pioneer and SoundStorm, and others may prefer resources aligned with the Buffalo Model. The method matters less than the match. What is important is that the child is engaged in meaningful, targeted listening tasks that strengthen the underlying pathways.

I do not believe bottom-up tools should be used in isolation. The reason is simple—they often don’t generalize well. Bottom-up tools can build precision, but without top-down practice, those gains rarely carry over into real-world communication. You need top-down engagement to integrate and apply these skills across different contexts, especially across areas of both weakness and strength. That’s what allows children to take what they’ve trained and actually use it in conversation, learning, and social connection. But I have seen firsthand how they can change lives when paired with broader supports. These tools give us a way to train the brain to hear more clearly, not just compensate for what is missing.

In fact, I consider the use of low-gain hearing aids a form of auditory training. It may not be behavioral, but it is physiological. When the auditory system is deprived or distorted, you need a physiological intervention.

If a child had a broken leg, you wouldn’t just send them to physical therapy. You would set the bone, use a splint or cast, and then begin rehabilitation. Low-gain hearing aids work the same way. They stabilize the auditory signal, giving the brain a clear, filtered version of sound that supports language, attention, and learning. Some people say they’re just a crutch, but I disagree. Giving kids access to consistent clarity helps brace their processing pathways. It reshapes the auditory map through lived experience, not just drills. These devices are worn all day, not just during therapy, and the passive exposure makes a long-term difference.

On average, most of my patients stop using them after about three years. That’s often when the system becomes strong enough to manage without them. Sometimes they return in high school or college, when listening demands increase and effort becomes a problem again. When that happens, the benefit usually returns too.

It reduces the cognitive effort that would otherwise be wasted on deciphering a garbled message.

These tools give us a way to train the brain to hear more clearly, not just compensate for what is missing. That is not just theory. It is observable. It is functional. And it helps.

In my practice, I offer low-gain hearing aids as a structured treatment trial. These devices typically provide about 10 decibels of subtle amplification to enhance speech clarity, but it’s more nuanced than just adding volume. The amount of power I use is no more than what is commonly used in over-the-counter FM systems like the Roger systems often implemented in schools. By using vented domes, I also block approximately 10 decibels of unfiltered sound. That blocked portion is replaced with a clearer, more filtered version of the signal, allowing for a kind of selective enhancement. It’s a lot like doing auditory dialysis. The system filters out some of the noise and replaces it with something more usable. This approach not only improves awareness of external speech but also heightens awareness of the child’s own voice through mild use of the occlusion effect. That self-awareness can support speech monitoring and social regulation in ways that are often overlooked. Families do not have to commit long term. We run a six- to eight-week period where we can observe real-world changes. This is not a vague or theoretical intervention. It functions like a medication trial. You introduce the treatment, observe the effects, then withdraw it.

If the child improves while using the hearing aids and regresses when they are removed, that is meaningful data. It gives us one of the clearest windows into whether access to sound is part of the problem.

One of the most compelling examples I’ve seen came from a teenager who had been evaluated years earlier and was found to have significant auditory processing challenges. He received no therapy and no drills. Only properly fit hearing aids that improved his auditory input.

Three years later, he returned for a follow-up evaluation with the same clinician. She told the family she had never seen a child make that kind of auditory progress without structured training. The only variable was daily access to a clear signal. That is what auditory support can do.

You see the same pattern in other cases. Children who spend years in articulation therapy without progress often make dramatic gains when the underlying auditory input is improved. One child I worked with had been in speech therapy for seven years. After just two months with low-gain hearing aids, she no longer needed services. Seven years of missed clarity. Seven years of being asked to correct what she may never have heard properly in the first place.

We cannot keep trying to treat what is likely a physiological condition with purely behavioral interventions. The original testing for auditory processing issues was actually based on identifying a site of lesion. Much of it originated from evaluations of soldiers who had sustained brain injuries during military operations. These individuals could no longer understand speech clearly, especially in noise, despite having normal hearing on the audiogram. Their difficulties pointed to a breakdown not in the ears, but in how the brain processed sound. It was rooted in the understanding that this was a physiological issue. Over time, especially with children, the cause often becomes harder to pinpoint. Developmental auditory processing issues may not have a clear, visible wound, but many are the result of early auditory deprivation. That might come from chronic ear infections, fluctuating hearing, or other subtle disruptions to sound access. Just because we can’t always locate the lesion doesn’t mean the problem isn’t real. It simply means the breakdown happens in a system still under construction. But it is still physical in nature. It is still physiological. It is certainly not behavioral.

The reality is, even though we may not be able to find an actual site of lesion, it is clear that auditory processing issues stem from physiological conditions. These include auditory deprivation from chronic otitis media, strokes, noise trauma, and other neurologically impactful events. These are not behavioral disorders. For that reason, they require physiological treatments. You do not fix brain-based auditory input issues by addressing only language or behavior. You need to support the system at the level where the breakdown begins. It’s like standing downstream in a polluted river and trying to clean the fish. You can spend all your energy scrubbing, but as long as the source remains polluted, the problem continues.

If the signal is broken, everything built on that signal will be unstable. Children should not have to fight upstream every day while we debate whose job it is to fix the water.

We cannot build literacy on a garbled signal. And we cannot fix a sensory-level condition with behavioral supports alone. It takes access, clarity, and practice.

There is no way for a speech and language intervention to fix auditory processing. You might be able to improve language or strengthen auditory closure skills, but that does not change the fact that the signal itself is distorted. What you’re doing is teaching the child to work around the distortion—to guess better, to infer more, or to fill in gaps based on stronger language. But that is still interpretation of a distorted signal.

What we should be doing is correcting the signal at the source. That is the only way to reduce the cognitive load and give the brain reliable access to language in the first place.

I once worked with a three-year-old girl with an autism diagnosis who had early access to ASL and received auditory support through low-gain hearing aids starting at age three. Her same-age half-brother, who was officially raised as her cousin, shared the same father. Their mothers are sisters, and both children were raised in overlapping households. They had nearly identical genetics, early diagnoses, and access to care. I began working with him at age five, two years later than his cousin.

For clarity, I often refer to them as “cousins,” but developmentally and genetically they resembled twins. Now, at age eight, the difference between them is striking. The girl is fully conversational and only slightly behind in school. Her cousin, by contrast, still relies heavily on echolalia and gestalt language. His speech often sounds sophisticated, but the language is scripted and inflexible. He remains on multiple medications and continues to need intensive behavioral support.

The difference was not effort, intelligence, or love. It was access. Specifically, it was access to language through ASL and auditory clarity through low-gain hearing aids during the critical window. When the signal is clear, whether through sound or sign, the brain can organize language. When it is not, development becomes fragmented. What changed their paths was not diagnosis or potential. It was timing, access, and support.

The double standard is glaring. No one demands brain scans for diagnosing dyslexia or mixed receptive-expressive language disorder. Those diagnoses rely on behavioral data, just like we do. And their tests are not more precise or predictive than ours. What matters is how you interpret those results within the broader context. When you combine test data with case history and interdisciplinary input, you can pinpoint where the breakdown is happening.

And I’ll tell you where it’s not happening. It is not downstream. It is not caused by poor articulation, effort, or language exposure alone. It begins upstream, with the signal itself. A distorted or degraded input will affect everything that comes after. We need to stop acting like speech and language issues emerge out of nowhere and start acknowledging that many of them are symptoms of auditory access problems.

And here we are, fighting for dominance over territory while the window of opportunity for many of these children is closing. Instead of uniting around the shared goal of giving them access, we are arguing about whose domain it is to address the problem. That delay has a cost. It is paid in missed milestones, misunderstood behaviors, and emotional fallout that could have been prevented if we had just focused on the signal and what it takes to make it clear.

APD still matters. The diagnosis matters. The children matter. And they deserve a full, interdisciplinary approach that includes amplification, training, environmental support, and language access. Not just one or the other.

Let’s do better. Together.

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