CVI and Central Auditory Processing Disorder (CAPD)

By Rachel Bennett

Maurice Belote has decades of expertise in the field of Deafblindness. Belote is a Deafblind specialist, Co-chair of the National Coalition on Deafblindness, adjunct faculty for two teacher training programs, and retired Project Coordinator for California Deafblind Services. In his video about Central Auditory Processing Disorder (CAPD) and its connection to CVI, Belote explores why we need CAPD on our radar when serving kids with CVI, the signs of CAPD, and strategies to support access to learning and the environment.

Why we need CAPD on our radar when serving children with CVI

Belote explores the question: What if there are some children and young adults who have CVI and who don’t seem to have typical responses to sound and speech but for whom Central Auditory Processing Disorder (CAPD) cannot and may never be accurately diagnosed?

I have over 30 years of providing child-specific technical assistance in California. I have had the privilege of going into probably thousands of school programs throughout California and have met children who have CVI and who pass all of the hearing screenings and hearing assessments but who don’t seem to have typical responses to speech or environmental sounds.
Maurice Belote

CVI and CAPD is a common topic in the CVI parent community, and some adults with CVI report difficulty processing sound and speech. This is an area that needs more research. Is CAPD common in people with CVI? Or does the difficulty with sensory integration for many with CVI impact auditory processing? For example, many with CVI are not able to look and listen at the same time, so if they are actively using their vision, they are not fully taking in auditory information.

Belote argues that if we suspect possible CAPD, there are things we can do that will help that child use their hearing better and won’t do the child any harm, and will also benefit other students in the classroom. These are simple strategies that we can all employ as educators, professionals, and families.

What is Central Auditory Process Disorder (CAPD)?

CAPD is the difficulty or deficits in the neural processing of auditory information, or when the brain has difficulty processing the sound taken in by the ears (asha.org). It’s when the brain and the ears don’t work well together. Sound familiar? CAPD is a brain-based hearing impairment similar to how CVI is a brain-based visual impairment. Belote describes, “Yes, that child with CAPD hears, but the sound that reaches the brain doesn’t reach the brain in a way that’s meaningful or useful in the same way for a child with CVI, where the eyes may be working okay [if there are no coexisting eye conditions], but the visual information that reaches the brain isn’t being processed in a way that’s meaningful or useful.”

Yes, that child with CAPD hears, but the sound that reaches the brain doesn’t reach the brain in a way that’s meaningful or useful.

Risk factors common to CVI and CAPD: hypoxia, anoxia, prematurity, seizure disorders, prenatal drug exposure, Cytomegalovirus (CMV), Hyperbilirubinemia, low birth weight, brain injury (e.g., head trauma, meningitis), stroke, hydrocephalus, hypoxic-ischemic encephalopathy, and genetic determinants.

Common signs of CAPD

Trouble paying attention to and remembering information presented orally
Problems carrying out multistep directions given orally, so they need to hear only one direction at a time
Poor listening skills
More time to process information
Distractibility
Difficulty localizing sounds
Difficulty hearing in noisy environments with a lot of competing sounds
Difficulty understanding speech that is too fast
Low academic performance
Behavior problems
Language difficulties (for example, confusing syllable sequences, problems developing vocabulary and understanding language)
Difficulty with reading comprehension and spelling, and vocabulary

How is CAPD diagnosed?

CAPD is typically in children over seven years or older who have traditional verbal language. CAPD cannot yet be diagnosed in children who do not have traditional verbal language. An audiologist assesses and diagnoses CAPD. Here are a few components of a typical CAPD testing protocol:

Auditory figure-ground: listen to a target voice over a lot of background noise
Dichotic listening: having different information in each ear and being able to listen to either both of them or being able to listen to one and ignore the information that’s coming in through the other ear
Auditory closure: finish a sentence or a statement or phrase in a song
Binaural processing: ability to localize sound to know where sound is coming from; tests the distance and the time it takes for sound to reach both ears
Temporal masking: when there are two competing sounds at different frequencies and the human ear will miss part of the sound just before and just after that the other sound is introduced

It’s important to note that traditional language is not required to be an effective communicator. Belote has worked with hundreds of children who are deafblind and who never acquire formal language but communicate very effectively through various communication approaches. So for students who are not able to be diagnosed with CAPD and who show signs of difficulty processing sounds and speech, what do we do?

6 strategies to consider for children with CAPD or suspected CAPD

Belote shared six strategies that will help students who have CAPD or suspected CAPD. He noted, “These strategies will likely help all kids, including students on the autism spectrum, students who have ADHD or learning disabilities, and students who have no disabilities.”

1. Decrease auditory clutter

The noise in an environment interferes with being able to attend to and process a single source of auditory information. If a teacher is saying something important about bringing permission slips or about an assignment that’s due, for example, and at that moment the air conditioning comes on in full force, that environmental sound is auditory clutter, and the student will miss what the teacher is saying. It’s critical to continuously be aware of noise in the classroom at any given moment.

Ways that teachers make the classroom environment quieter:

Tennis balls on the feet of chairs, so when a student moves their chair, it won’t make a sound on the floor
Add curtains or drapes to the windows, walls, or in front of bookshelves to dampen the sound in the room (which can also help reduce visual clutter and distracting light from windows)
Set times to sharpen pencils

There are also high-tech options to help reduce auditory clutter in the classroom and help students hear the signal over the noise.

A sound field system is an amplification system where the teacher typically wears a microphone, and there are a series of speakers either in the ceiling or placed in the corners of the room that amplifies the teacher’s voice just a little bit (not like a PA system, but just a little boost). This helps the child hear the teacher’s voice over the everyday noise of the classroom.
Remote microphone technology (RMP) or FM systems is where the teacher wears a microphone, and the sound goes directly into the child’s headphones, hearing aid, cochlear implant, or whatever kind of amplification device they have.

2. Allow sufficient time for auditory processing

Build in plenty of time for the child to process information (30, 45, 60 seconds, or a certain period of time revealed during assessment). These periods of wait time are not unusual for children who are on the deafblind spectrum. Those with CVI and CAPD, or suspected CAPD, need more time for both auditory and visual processing (and sensory processing in general), especially if there’s competing sensory information.

3. Consider your rate of speech

One of the most effective things a family member or professional can do to support children is to slow down their rate of speech. Research shows that the central nervous system can only fully process language at certain rates, and there are limitations to how much it can process when the rate of speech is too fast. Often families or school staff are speaking at a rate faster (160-180 wpm) than younger children can physically comprehend (the best range is 124-140 wpm).

Depending on age, studies show a child’s central nervous system can process speech with reasonable accuracy when words are spoken at a rate of approximately 124 to 140 words per minute. The problem is, the typical adult rate of speaking is 160 to 180 words per minute. Many teachers and parents unknowingly speak too quickly to children, and then complain that they aren’t listening.
Dr. Ray Hull

Fred Rogers, the famous children’s television host of Mister Roger’s Neighborhood, is a master at speaking at 124 words per minute. Belote shares an example of this in his video above. When speaking with students, channel Fred Rogers and slow down, really slow down.

4. Use a multisensory approach but consider the limits of simultaneous multisensory input

We know that students with CVI benefit from using multiple forms of learning media to access their learning (auditory, tactile, kinesthetic, visual). But for some with CVI, we have to be careful that it’s not too much sensory input at the same time—they may only be able to effectively take in information through one sensory modality at a time.

When a child is focused visually, looking at something and paying attention, it’s not a good time to expect that same focus and attention auditorily. Stay quiet as the student is using their vision. For some with CVI, even just moving around the world while taking in visual information can take up a lot of effort and energy, which means they may miss auditory information. We hear a lot from people with CVI that if they want to listen to something, they cannot look simultaneously. Listen only or look only. And this is not limited to vision and hearing. If a child is exploring something tactually, they may not be able to use vision or auditory skills. This is why it’s so important to have a comprehensive understanding of the whole child—understand how they use their vision and how they use their compensatory skills.

5. Consider the significance of suprasegmental phonemes

Suprasegmental phonemes refer to the parts of speech and comprehension in spoken language that are above and beyond the sounds we use to form words (phonemes). We use suprasegmental phonemes to convey meaning. Below are five examples of common suprasegmental phonemes and why we have to consider them when talking to a child with CVI and CAPD or suspected CAPD.

Stress

There is a lot of information that is conveyed in spoken English by changing the word (or part of the word) that we emphasize. The meaning of a sentence (or word) can change depending on the word we stress. For example, take the sentence, “You lifted that heavy ball.” If we stress the word “you,” then it conveys surprise and a question about whether or not you are the person who lifted that heavy ball. If we stress the word “heavy,” then focus on the heaviness of the ball is emphasized, changing the meaning to more of an excited statement about achievement. For some of our students, this stress can be missed, so it’s important to be clear about what you are trying to convey. For example, “I’m going to ask you a question: Did you lift that heavy ball?” or “I’m excited because you lifted that heavy ball.”

Juncture

Juncture is when words naturally blend together while speaking quickly and proficiently—you can’t tell where one word ends and the next word begins. This is a natural part of speaking. But when we don’t break up words individually, comprehension can be much more difficult. One example is “ice cream” and “I scream.” Two very different meanings, but without the pause, these distinct meanings can be missed. Insert a little space between particularly important words, whether teaching new vocabulary or sharing something important to the child’s interest.

Pitch

Pitch is when our speech goes up and down, high and low. When we ask yes or no questions, the pitch in our voice goes up at the end of the question. For example, say aloud, “Would you like another donut?” Your pitch likely went up somewhere in the word “donut.” But when we ask open-ended questions, our pitch does not usually go up at the end. For example, “Who made this mess?” If the pitch of “mess” went up, it wouldn’t sound right. When we convey certain emotions, our pitch can change. For example, for some, the pitch can go up with surprise or excitement, while the pitch can go down with sadness or anger. Think about what is happening with the pitch in your voice when you convey certain emotions, ask a yes/no question, or make a declarative statement. Pitch affects meaning, and pitch can often be missed by some students with CVI and CAPD or suspected CAPD.

Tone

Tone is how you say something, whether you say it nicely, angrily, frustratingly, or embarrassingly. Just like pitch, tone affects meaning. Often, people learn the tone of emotions through visual cues, such as facial expressions, body language, and gestures. For students with CVI, these visual cues may be missed, leaving them with a voice change that is unrecognizable in someone very familiar. So an angry tone might sound like a parent is making a silly voice, and the child laughs in response. Or the tone might be missed altogether. Missing tone and pitch can compound and make it difficult to understand what was said. Again, be crystal clear about what you are trying to convey to a child with CVI. For example, “You might hear that my voice sounds different. I am angry right now. My voice shows my feeling of anger. I am angry because…” Consider keeping the tone and pitch as even and predictable as possible.

Tempo

Tempo is the speed at which we say something. Remember, consider Fred Rogers or another example of someone who speaks slowly and clearly.

Key Takeaways

Slow your rate of speech, create space between words, and consider if the stress, pitch, and tone of your voice are accessible. Clearly describe what you are trying to convey in your speech. For example, “I have a question for you,” “I need to tell you something important,” or “I am feeling sad right now and this is why.” Keep it direct, clear, and concise, with an even tone and pitch.

6. Support sound localization by drawing attention to sound sources

Vision and hearing are distance senses. When we hear something, either near or far away, we turn our heads to help our ears and brain to locate the sound, and then our vision verifies what is making that sound and where it’s exactly coming from. We need to move our heads to compensate for the limits of the human ear, which has a hard time hearing the difference between sounds coming in front or behind you.

For some with CVI, various factors can affect the ability to localize sound, such as difficulty scanning the environment, visual field loss, distance vision, and recognizing targets in a cluttered environment. Belote notes that he particularly worries about localization with children who don’t have a lot of voluntary movement. For example, a student who is a wheelchair user and needs a headrest may not be able to turn their head to figure out the sound source.

To help support sound localization, draw attention to sounds in the environment. For example, stand next to a classmate speaking, verbally describe the sound and where it’s coming from, or bring the item making the sound close to the student.

Context is everything

We must ensure that children understand the context of what we’re talking about. If we make a sudden shift in subject matter, we must bring the children along with us on that shift and say, “Oh, I was talking about this book we were reading, but now I’m going to shift gears and mention that I desperately need a tissue. So we’re going to stop the storytelling just for a moment while I go get a tissue.” Directing students through that shift in subject matter helps them understand that the teacher’s need for a tissue is separate from the discussion about the book. For some with CVI, they might miss those visual cues from the teacher that notes that shift. We also know that context is used as a compensatory skill for some with CVI to help predict and make meaning of the environment, task, and learning activity that is not fully visually accessible. Make sure the context is always clear and known to the student.

Always, always think about the whole child when serving students with CVI. There are children with CVI who have passed their hearing screening and assessments but whose families or providers might be saying, “I know they’ve passed all their hearing tests, but I’m telling you, it just doesn’t seem like they hear right. They’re not having typical responses to sound.” Serving the whole child means understanding this learning need, observing, implementing strategies for access, and collecting ongoing data to ensure the student is making effective progress.

Ready for more? Explore CVI Scotland’s article on CVI and the challenges with sound and noise.