Sound waves are meaningless until they are processed by the auditory cortex where these electrical impulses are interpreted and meaning is given to these sounds. Constant stimulation is required for the brain to develop and this is why pediatric hearing loss is referred to as a neurodevelopmental emergency!
Children with normal hearing (0 – 15 decibels across all frequencies) learn up to 85% of information through incidental listening (over hearing). This ability allows them to constantly develop and stimulate their auditory cortex for language and communication with no direct instruction to learn new concepts and vocabulary. A child with hearing loss does not have this capacity, even a mild hearing loss can cause the sound to be softer and unclear. As a result, children with hearing loss require direct teaching of most skills and knowledge that other children learn through incidental listening.
Signs & symptoms that your child may have hearing loss
- Your baby doesn’t startle at loud noises by one month
- Your baby doesn’t turn to the source of a sound by three to four months of age
- He doesn’t notice you until he sees you.
- He concentrates on gargling and other vibrating noises that he can feel, rather than experimenting with a wide variety of vowel sounds and consonants.
- Her speech is delayed or hard to understand, or she doesn’t say single words such as ‘dada’ or ‘mama’ by month twelve or fifteen.
- She doesn’t always respond when called (this is usually mistaken for inattention or resistance, but could be the result of a partial hearing loss).
- He seems to hear some sounds but not others (some hearing loss affects only high pitch sounds; some children have hearing loss only in one ear).
- She seems not only to hear poorly, but also has trouble holding her head steady, or is slow to sit or walk unsupported (in some children with sensorineural hearing loss, the part of the inner ear that provides information about balance and movement of the head is also damaged).
Information supplied by Surida Booysen, Pediatric Audiologist at Carel du Toit Centre.
A variety of tests are performed when a child is diagnosed with hearing loss. Please view more details about these tests here.
How to read your child’s audiogram:
Once these test have been conducted, your child’s hearing loss will be plotted on an audiogram.
Across the top of the graph are the numbers representing pitch/frequency from low to high. On the left side of the graph are the numbers representing loudness of sound. Your Audiologist will be interested in measuring the softest sound your child can hear, this is referred to as your child’s hearing threshold.
On the graph ‘x’ is the responses for the left ear and ‘o’ is the responses for the right ear.
- 15 – 25dB slight hearing loss
- 25 – 40dB mild hearing loss
- 40 – 55dB moderate hearing loss
- 55 – 70dB moderately-severe hearing loss
- 70 – 90dB severe hearing loss
- 90dB and above is profound hearing loss
What does it sound like:
As a parent or caregiver you may wonder what your child’s hearing loss sounds like. Watch this video to get a better idea of your child’s hearing.