Parents often worry about whether or not their baby's hearing is normal. There is certainly reason for concern. Lack of hearing can greatly interfere with an infant's development.
Profoundly deaf babies are slowed down in all areas. They are likely to appear depressed and unreactive -- slow to develop motor skills and to reward parents' attempts at interaction. They may lie in their cribs passively, or they may develop autisms -- such as head rolling or other repetitive behaviors -- as if to fill up empty space.At the same time, their other senses, such as sight and touch, become heightened. This can make a baby hypersensitive and easily overwhelmed.
Fortunately, there are ways to test the hearing of a baby. I find it is best to do it when she is asleep or as she is just rousing. I use a soft rattle and a bell, in a quiet room. After several startles, a baby with normal hearing will shut out or ignore either of these sounds.
A quiet room is one of the keys to this assessment. If I test a baby in a noisy environment, she may have already shut out auditory input.
Then she can appear to be deaf, even though she's not. The reason for the two stimuli is to test the range of her hearing.
Another test would be to give the baby a chance to respond to my voice when she's awake and looking at the ceiling. If she quiets and slowly turns to my voice, I know that she hears me. If her mother and I compete on either side of her, she should choose the higher-pitched female voice.
If there is concern about a baby's hearing, the primary physician usually refers the child to an otolaryngologist (ear and throat specialist), who can examine the ears and upper respiratory tract. If the cause is a temporary condition, the otolaryngologist will provide treatment. If the hearing loss seems permanent, the child may be referred to an audiologist who can perform further tests.
Tests, such as auditory evoked responses (AER), can detect major hearing impairment in babies -- before it interferes seriously with the child's development. If there is any indication that a baby is not hearing or hears in certain ranges but not in all, I'd suggest a complete evaluation.
Hearing loss may become more obvious in the second year, as a child who is beginning to speak garbles words in a regular fashion. I would always be aware of hearing impairment as a possibility in a child who is not developing properly, particularly in areas of communication.
Otitis media (infection of the middle ear) can threaten a child's hearing. Many infants develop a tendency to chronic otitis media. After an acute earache, the pressure and the discharge seem to linger despite antibiotics. Otitis media is sometimes called glue ear -- as if the ear contained glue that was hard to mobilize.
Chronic infection of the middle ear can cause hearing impairment. Infants in group care or infants with older siblings in school who are exposed to many different infections are particularly vulnerable.
Ear infections may follow colds as often as every two weeks. Each ear infection becomes more difficult to treat. Parents and physicians get discouraged. The baby's general condition is often affected; she seems to become run-down and vulnerable to everything.
At this point, an ear and throat specialist should be consulted. It may be necessary to use tubes in the child's eardrums. They allow drainage, reduce pressure in the inner ear and prevent hearing loss.
Following the development of speech and other forms of communication is the most important way of determining whether there is hearing loss.
With an older child, if you are concerned about hearing, try whispering in one ear or the other. Be sure to whisper something to which you know she will want to respond, since there are many periods in a child's development when selective attention can be operating. Whisper a welcome question, such as, Do you want to go to town with me? or Do you want a cookie? In my office, I put my finger in one of the child's ears and whisper in the other, Do you want a lollipop? This is almost sure to get a response. If there are no responses and/or speech is developing inappropriately, I refer the child for evaluation by an otolaryngologist or testing by an audiologist.
In future columns Dr. Brazelton will answer selected questions from readers. Questions or comments should be addressed to Dr. T. Berry Brazelton, c/o The New York Times Syndication Sales Corp., 122 E. 42nd St., New York, NY 10168. Questions of general interest will be answered in this column; Dr. Brazelton regrets that unpublished letters cannot be answered individually. T. Berry Brazelton, M.D. Dist. by New York Times Special Features