Why is it important to get a hearing assessment if my child has a speech delay?
One of the first questions a speech pathologist will ask you in an initial speech assessment is whether you have had your child’s hearing assessed. Having a hearing assessment done is a vital part of the assessment and diagnostic process for a number of reasons. Children learn to speak through listening and replicating our speech output. Therefore it is important that children are receiving a clear speech sound input to produce speech sounds correctly. Even a temporary ear infection can cause speech sounds to be distorted and sound muffled, making it impossible to understand speech. Their hearing may sound similar to when you go swimming and you hear someone speaking when you are under water.
A common misconception that parents have in regards to hearing is that they assume because a child is able to hear other noises such as pots and pans or the garbage truck outside they are able to hear fine. This may be the case; however, different sounds have different frequencies. The child may be able to hear these loud low frequency sounds but still have an impairment affecting a certain frequency range that encompasses some or all of the speech sounds. The Speech Banana to the left shows how speech sounds falls into a small range of the sound spectrum highlighted yellow. An impairment in high frequency sounds for example the 0-40dB range may mean they just have difficulty hearing the ‘f’, ‘th’ and ‘s’ sounds. This type of hearing impairment is similar to how we confuse ‘f’ for ‘s’ on the telephone, as high frequency sounds tend to be cut off by the telephone just as they would for someone with a mild hearing impairment.
The results of the hearing assessment are important in determining the type of speech therapy required and can give an indication of how long the child may require therapy. The hearing impairment may be a conductive hearing loss which is usually a temporary condition or a sensorineural hearing loss which is permanent. A conductive hearing loss means there is a problem with the transfer of sound through the outer or middle ear often due to ear infections (e.g. glue ear). These are commonly treated with a course of antibiotics. Once the ear infection has cleared the child may then need to see a speech pathologist for a short period to assist in getting his/her language up to speed to an age appropriate level. A Sensorineural hearing loss means there is damage to the inner ear or the 8th auditory nerve. In most cases this requires ongoing therapy for longer periods of time and may need surgical intervention such as cochlear implant or hearing aids to improve hearing, in conjunction with regular speech therapy.
This article was written by our speech pathologist Ashleigh Fattah. If you have questions about speech pathology and hearing or any speech related fields, contact ENT Clinic on 1300 123 368 and make an appointment with our speech pathologists.