An informational update from the Western PA School for the Deaf November 13, 2014
Training Summary & Additional Info by Tamara Guo, M.Ed. Developmental Specialist
The Eunice Kennedy Shriver National Institute of Child Health and Human Development reported in 2012 that 1 in every 33 babies are born with some type of birth defect. Prematurity and low birth weight are primary causes of birth defects. Other factors that contribute to birth defects include genetic/chromosomal conditions, exposure to bacteria and/or viruses, cigarette smoke, maternal diabetes, drug & alcohol use and exposure to chemicals. There is no definitive report on the number of children born with hearing impairments, although according to the American Academy of Pediatrics hearing loss is one of the most frequently occurring birth defects; approximately 3 infants per 1,000 are born with moderate, profound or severe hearing loss.
What Causes Hearing Loss?
Hearing loss can be caused by a variety of factors including inherited or congenital problems, infections, diseases or trauma (affecting the inner ear or hearing mechanisms).
Hearing loss can be congenital, or acquired. Congenital hearing loss arises from an infection or illness a mother develops during pregnancy such as CMV, rubella, herpes, syphilis or HIV or from various genetic syndromes such as Down Syndrome, Usher Syndrome, Treacher Collins Syndrome, Crouzon Syndrome, Alport Syndrome, Sickle Cell Disease, Tay-Sachs Disease, Waardenburg Syndrome, Pendred Syndrome, Goldenhar Syndrome and CHARGE Syndrome.
Acquired hearing loss can result from ear infections, ototoxic medications, meningitis, measles, encephalitis, chicken pox, mumps, head injury or noise exposure.
Some risk factors for hearing loss in the newborn period include low APGAR scores (below 4 at one minutes and below 6 at five minutes), low birth weight under 3.5 pounds, a NICU stay greater than 5 days and jaundice that requires transfusion.
Some malformations of the head, neck or middle ear such as atresia (absence or incomplete formation of the ear canal), microtia (small, abnormally shaped or absent outer ear) and cleft palate can be related to hearing loss.
The National Center for Hearing Assessment and Management (NCHAM) reports that detecting and treating hearing loss at birth for one child saves $400,000 in special education costs by the time that child graduates from high school.
State Laws (from NCSL.org)
Thirty-six states, Guam, Puerto Rico and the District of Columbia require hearing screening for newborns, including: Arizona, Arkansas, California, Colorado, Connecticut, Delaware, Florida, Georgia, Hawaii, Illinois, Indiana, Iowa, Kansas, Louisiana, Maryland, Massachusetts, Minnesota, Mississippi, Missouri, Montana, Nebraska, New Jersey, New Mexico, New York, North Carolina, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, Tennessee, Utah, Virginia, West Virginia and Wyoming.
Seventeen states, Guam, Puerto Rico and the District of Columbia require specified or all health insurers to cover the screening, including: Alaska, Delaware, Florida, Indiana, Maine, Maryland, Massachusetts, Mississippi, Missouri, Nebraska, New Jersey, New York, Rhode Island, Tennessee, Texas, Virginia and West Virginia.
At least three states—Massachusetts, Ohio, and West Virginia—have laws that specify who shall pay for the screening if the facility is not reimbursed by a third-party payer and parents are unable to pay. A number of states have created task forces or advisory committees on newborn hearing screening.
What Are the Types of Hearing Tests Used for Newborns and Infants?
Otoacoustic Emissions (OAE’s): are used for newborns as a screening or part of a larger diagnostic test battery. When a sound stimulates the cochlea, the outer hair cells vibrate. The vibration produces a nearly inaudible sound that echoes back into the middle ear. This sound can be measured with a small probe that is inserted into the ear canal. With hearing loss greater than 25-30 dB, OAE’s are not present.
Auditory Brainstem Response (ABR): gives information about the inner ear and brain pathways for hearing. An ABR can be used as a screening or diagnostic method depending on equipment and the professional conducting the test (nurse vs. audiologist).
When hearing loss is suspected via a screening a comprehensive hearing evaluation with the input of an audiologist is conducted.
What Types of Testing Are Used for Toddlers?
Children over age 6 months and up to about age 2 years can benefit from Visual Reinforcement Audiometry, where they are trained to look toward a sound source. When a child gives a correct response by looking toward a sound source they are reinforced or rewarded visually. Older children ages 2-5 can be trained to perform an activity each time a sound is heard. The activity can be something like placing pegs into holes, putting a block in a box or putting a ring onto a post.
What is an Audiogram?
An audiogram is a graph that shows the softest sounds a person can hear at different pitches or frequencies.
- Normal Hearing on Audiogram is -10 to 15 dB
- Minimal Hearing Loss on Audiogram is 16-25 dB (may miss sounds TH, S, Z)
- Mild Hearing Loss on Audiogram is 26-40 dB (may miss above sounds +M, D, B, H, G, K)
- Moderate Hearing Loss on Audiogram is 41-55 dB (may miss all above sounds + N, NG, CH, R, SH, ALL VOWELS)
- Moderate to Severe Hearing Loss on Audiogram is 56-70 dB (from moderate loss upwards speech cannot be understood, people can hear some speech, but not understand it)
- Severe Hearing Loss on Audiogram 71-90 dB
- Profound Hearing Loss on Audiogram 91+ dB
Unlike glasses, hearing aids will help a person hear, but not make hearing “normal” like glasses do for correcting vision. You can read our article on Cochlear Implants here.
Here is a link to a hearing loss simulator to help you better understand what speech sounds like to someone with varying degrees of hearing loss:
If your child shows no indication of hearing loss, it is still important to see that they receive a hearing screening as they grow. According to the Centers for Disease Control and Prevention (CDC), the American Academy of Pediatrics (AAP) recommends that school-aged children receive hearing screenings:
- When they start going to school
- At least once at ages 6, 8, and 10
- At least once during middle school
- At least once during high school
For children with other known health or learning needs; speech, language, or developmental delays; or a family history of early hearing loss, hearing screening might be required more often.
Because children learn to speak by listening, children with unidentified hearing loss often have trouble learning to speak, and they experience delays in their language and speech development. For this reason, it is important to pay careful attention to causes of hearing loss in children, and how quickly and well your child is learning to speak and understand language when compared to other children of the same age. If something doesn’t seem right, ask your doctor.
References and helpful websites for hearing loss: