Hello, my name is Heidi Slager. I'm an audiologist at the University of Michigan cochlear implant Program, and I'll be speaking with you today about hearing aids. I'd like to take a moment to acknowledge the cochlear implant team at University of Michigan, whose collective efforts have brought you this information today. As an overview, a hearing aid is a small electronic device that's worn behind or in the ear. Hearing aids amplify and shape the sound so that a person with hearing loss can listen, communicate, and participate more fully in daily activities. In children, hearing aids have the ability to provide a child with access to the speech sounds that they need to be able to listen and learn. The type of hearing aid a child needs is determined both by the degree or severity, and the shape of their hearing loss. There are different types of hearing aids. Generally, the larger the hearing aid, the more powerful it is. So as someone's hearing loss becomes more severe, they will require a more powerful, larger hearing aid to provide them with optimal benefit. Children are usually fit with behind the ear type hearing aids because they use ear molds, which can be replaced as their ear grows, and they also have child-friendly features. Pediatric hearing aids have a set of features that make them uniquely suited to the needs of a child. These hearing aids are capable of fittings using pediatric prescriptive methods, which emphasize the audibility of sounds because a child will only learn to say what they're able to hear. They also have battery door locks, which prevent accidental ingestion of batteries which are toxic. They have LED indicator lights, which allow a parent to tell when a hearing aid is on, off, or when settings have been changed. They're compatible with hearing assistive technology that children need to be able to hear and background noise, such as in the classroom. These include FM, DM, or remote microphone Systems. Early access to sound in children is critical. This is because children need a clear signal as early as possible in life in order for their brains to develop a complex foundational network of neural connections that will support the development of listening and spoken language throughout their childhood. To meet this goal, children should at a minimum have a hearing screening by one month of age, their hearing loss should we diagnosed by three months of age, and their hearing aids should be fit by six months of age. Ideally, we fit children even younger than these goals. The reason for this rush is that there's a critical window for the development of spoken speech and language, which is from birth through three years of age. This is when the brain's neuroplasticity is the greatest, and stimulation of the auditory cortex during these early years actually influences the organization of the brain's auditory pathways. If the brain isn't stimulated with auditory input, the connections won't develop, they won't be as strong, or they'll be used for different brain functions altogether. So how does a hearing aid work? There are four basic parts to the typical hearing aid. The microphone receives the sound and converts it to an electrical signal. The amplifier increases the power and shapes the signal to the child's hearing loss. The speaker receives the amplified sounds and sends it acoustically back to the ear. The ear mold couples the hearing aid to the ear and prevent sound leakage which can cause feedback. The goal of any hearing aid fitting is for a child to develop age appropriate speech and language. In order to achieve this goal, the aid must first be fit so the child has access to all sounds of speech, including the soft high pitch consonant sounds. The tricky part is that audibility does not always equate to intelligibility. Similar to the sound distortion you hear when you turn a radio up too loud, having a hearing aid set improperly, or having a degree of hearing loss that requires the hearing aid to be turned up extremely loud will result in a distorted speech signal. These distortions will be reflected in the child's speech intelligibility, as well as their progress with speech and language. So it's important that a child undergoes regular speech and language evaluations to help determine the quality of the sound they are receiving. When a hearing aid is fit, it is both to the child's hearing thresholds, as well as their individual ear canal size, and this helps ensure that the correct amount of sound is reaching the child's eardrum. This is done using a test called Real Ear Measures. Real Ear Measures aid the audiologist in matching the gain or power at each frequency to prescribe targets which are based on research, and provides us with an estimate of the speech intelligibility expected with the hearing aid fit. First about that, once you hear a new sound. Yeah. Sometimes, they just get really excited about it. I can't decide, I think you may stop wiggling, I'm going to guess it. So I've turned it on, now I'm going to squiggle it into his ear, he's going to hear a little bit of music while I'm getting started. It's like a warm-up song, it gives you some time to get in your ear. Then hi, well, there it is. Where is he going? What do you think? What's going on? What do you think? Can you hear me? Can you hear me super good? Hi. Hi. I got another one. Let' try it. Let' try it. You look at mummy, and then we'll let daddy talk. Hi, my son. She's going to put it in, and then she's going to fit it. Then she's going to fit it. You got to let her. He's like, what are we doing? Where's that music? Where's that good sound? He's just got the wiggles right now. Yeah, wiggles. Got it. There we go. Same alignment. Yeah. It's still on over to the right side, it's on over there, huh? I'm going to do the same thing, turn it on. That way I don't catch any of his hair because this hair comes comes over his ear. So I kind of cut it a little bit. You absolutely do that when you try to snap and shut back there, and then that can pinch and hurt. Here we go. Hold still. Great. I've got it. Once a hearing aid has been fit, the real work begins. It's important that the child uses their hearing aids all waking hours in order to learn to listen and to develop spoken language. A child needs to use their hearing aids a minimum of 10 hours a day in order to achieve optimal outcomes. In addition to regular device use, appointments are needed to monitor the hearing loss, to adjust the hearing aids if changes in hearing occur, to make new earmolds to account for growth, to ensure appropriate device use and function, and to evaluate the benefit the child receives from their hearing aids. The outcomes of hearing loss study has shown us that children who wear hearing aids full-time, have grammar and vocabulary skills similar to children with normal hearing. Conversely, children who did not where they're hearing aids consistently, regardless of whether they have a little or a lot of hearing loss are at risk for poorer language outcomes. So these choices made when a child is very young will affect them throughout their life. It will affect their expressive and receptive communication abilities, their social skills, their executive function, their literacy, their ability to attend college and their ability to get and maintain a job. These aren't light questions and light decisions that we're making in this child's life. So it's imperative that children wear their hearing aids at least 10 hours a day with a high quality hearing aid fit. So they're likely to have age appropriate skills by the time they enter school. There are tools available for us to help parents keep the hearing aids on their child. Children will pull the devices off their ears. Particularly when they're young and have just started using them. Parents must commit to enforcing device use and teach children early that only adults are allowed to put on or take off their hearing devices. The quicker a child learns this, the better they will tolerate their hearing aids, and they will tolerate them better if use has been enforced since they were very young, ideally a baby. As they get older, fun earmold colors and hearing aids stickers can entice them to wear their aids more often, and there are retention aids available. These include double stick wig tape, pilot caps and shirt clips which ensure the devices stay on and don't get lost. In addition to fitting the aid, we are on an ongoing basis evaluating the benefit of a child receives from their hearing aids. Benefit is evaluated in a few different ways. We look at functional gain in addition to the real ear measures we discussed previously. This ensures the child is hearing very soft sounds including those sounds of speech. A child speech recognition or their ability to correctly identify or repeat words using only their hearing is evaluated in order to ensure they are receiving a clear signal from their hearing devices, and a speech and language evaluation evaluates the child articulation, spoken language, expression, comprehension, language levels and literacy, to ensure that appropriate progress is made. Actually, all children with hearing loss should have a speech and language evaluation, regardless of the device that they are using. To summarize, hearing aids improve the audibility of speech and environmental sounds. They are able to provide children with the access to sound needed to develop spoken speech and language. However, they must be fit early to provide optimal benefit and a child must use them all waking hours. Hearing aids, do not allow children to hear speech clearly in the presence of background noise because they do not restore normal hearing, they restore access to sound. So children will need assistive listening devices such as FM systems and remote microphones in order to hear clearly in the presence of background noise such as in the classroom, and hearing aids may alter the sound quality of both speech and environmental sounds. So it's important that a child undergoes regular speech and language evaluations to ensure appropriate progress is made. So now you know a lot about hearing aids and how they work and how we fit them. But aside from a hearing evaluation, what are some red flags that a child may need hearing aids or need a hearing evaluation? In infants, red flags include not startling or jumping to sudden loud noises, not turning the head or eyes towards the sound by six months, and not imitating some sounds and producing a few words by 12 months of age. In older children, red flags include: limited, poor or no speech, frequent inattentiveness, difficulty learning, listening to the television at a high volume, not responding to conversational speech, answering questions inappropriately, not responding to their name or becoming easily frustrated in background noise. Hearing loss is fairly easy to diagnose or rule out as a cause of any of these symptoms. So I encourage you to consider referral for a hearing test anytime you see these symptoms. So what do we do when hearing aids are not enough? There are situations when a child is not receiving the benefit expected from a hearing aid. This can occur if the device is not fit properly or if their hearing loss progress is over time. In cases of hearing loss progressing over time the child may be referred for a cochlear implant evaluation. This doesn't guarantee that they will receive a cochlear implant, but it does ensure that they receive the thorough evaluation to determine if they could benefit from a cochlear implant, and also if they will not benefit from a cochlear implant it can help facilitate referrals for other evaluations such as neuropsychology or developmental pediatrics, to identify the reason for a limited progress with implification. In conclusion, a child should be referred to be fit with hearing aids as soon as a hearing loss is diagnosed, even if it is a mild or a unilateral hearing loss. A child should be referred for a hearing evaluation, when they fail to meet appropriate speech and language milestones. A child should also be referred for hearing evaluation when a parent or other professional working with the child expresses concern regarding their hearing or language or when red flag behaviors are observed. We used to advocate waiting and watching to see if the child could work out their speech and language issues on their own, but we now know the importance of early development of the brain. So we advocate for early referral for hearing evaluations anytime any red flags are observed. Thank you for taking the time to speak with me about hearing aids today, and I appreciate it.
