What is hearing loss?
Hearing loss challenges a person’s understanding of speech and other sounds in a way that is different from most people who do not have hearing loss. Hearing loss may be “unilateral” (affecting one ear) , or “bilateral” (affecting both ears).
There are different types of hearing loss which may affect the type of intervention recommended as well as different degrees of hearing loss, which are medical terms used to describe how much your child can or cannot hear. We usually assume that it means that something is wrong (malformed, damaged) with the structures of the ear, but it can also mean challenges in how the brain processes the auditory signals delivered from the ears.
This section provides information about ‘normal’ hearing levels for children, the different types/degrees of hearing loss and some information on how to improve the outcomes so that children with hearing loss can achieve their best.
The most common types of hearing loss are related to the structure of the ear (outer, middle or inner ears) but it can also mean challenges in how the brain processes the auditory signals delivered from the ears.
There are basically two types of structural hearing loss:
Conductive hearing loss indicates a problem with the mechanism that conducts sound from the environment to the inner ear. Problems in the outer ear (pinna and ear canal) or the middle ear (ear drum or the bones of hearing) may cause a conductive loss.
While this type of loss can usually be corrected by medication or surgery, there are some issues that result in a permanent conductive hearing loss. If the hearing loss cannot be corrected, the child can usually do very well with hearing aids. The audiologist will determine the type of hearing aid that would be best for your child.
Some conductive hearing losses are fluctuating or transient. These hearing losses are typically the conductive type, due to an ear infection, and are usually temporary and resolve themselves. However, if the child is experiencing many ear infections that go untreated they can cause collective damage (i.e., cholesteatoma) and possibly a sensorineural (permanent) hearing loss.
Sensorineural hearing loss indicates a problem in the inner ear .There may be damage to the cochlea, or along the nerve pathway between the cochlea and the brain. This kind of loss cannot be medically “cured” at this time. However, children with sensorineural hearing loss can benefit from hearing aids, FM systems, cochlear implants, communication therapies, and a careful analysis and implementation of educational and communication approaches.
Sensorineural hearing loss can be congenital, acquired, sudden or in some rare cases fluctuating. Sensorineural hearing loss can be acquired by over exposure to noise.
Mixed hearing loss refers to a combination of conductive and sensorineural hearing loss. This means that there may be damage in the outer or middle ear and in the inner ear or auditory nerve.
Sorting It Out – Four Types of Hearing Loss – conductive, mixed, sensory, and neural hearing loss issues – downloadable handout
Other types of hearing disorders:
There are other types of hearing disorders that are not necessarily related to the structure of the outer, middle or inner ears.
Auditory Neuropathy Dyssynchrony Spectrum Disorder (ANSD), also known as auditory dysynchrony, means that the cochlea (inner ear) is actually functioning normally but the sound information is not accurately sent to the brain. Auditory neuropathy may be inherited or caused by trauma/disease.
Auditory Processing Disorder (APD) is a hearing problem that affects about 2-3% of children (Chermak and Musiek, 1997). Children with APD typically have normal hearing ability but can’t make sense of what they hear in the same way other children do because something disturbs affects the way the brain recognizes and interprets sounds, especially speech.
Hyperacusis is not a hearing loss. It is on over-sensitivity to sound that can impact daily a child’s ability to function in daily life. Because children are often unable to describe their discomfort they often resort to emotions or behaviors to communicate their experience. These may include crying in noisy environments, clasping hands over the ears, fear of noise or noisy objects, self-harm when exposed to loud noise, i.e. vacuum cleaners, and reluctance to participate in noisy or loud activities (e.g. watch parades, birthday parties, musical presentations). Children with Autsim or Asperger’s Spectrums may experience hyperacusis or children can aquire hyperacusis following frequent or severe ear infections, head injuries, viruses, or medication adverse reactions, or unknown causes.
Degrees of Hearing Loss:
Hearing loss is described using words and numbers. The audiologist will explain the degree of hearing loss on a chart called and audiogram. Where the X and O markings fall on the audiogram will determine the degree of hearing loss. Hearing loss can be:
The words “deaf” and “hard of hearing” are often used to describe individuals with hearing loss. These words do not describe the degree of loss but rather the mode of communication used by that individual. It is possible for two people to have the same degree of hearing loss yet use different way of communicating. For example a child with a profound hearing loss who uses cochlear implants and speaks would be considered “hard of hearing” whereas a child with the same degree of hearing loss who communicates with sign language would be considered “deaf”.
While each level of hearing loss brings with it specific challenges, it is critical to understand that ANY degree of hearing loss is educationally significant and will require intervention and supports.
Want to do a fun activity with children to teach them the parts of the ear and how it works? Try the EDIBLE EAR! Use food items for fun and learning. See the Edible Ear for a list of materials and a visual of the finished ‘ear.’
Chermak, G. & Musiek, F. (1997). Central Auditory Processing Disorders: New Perspectives. San Diego, CA: Singular Publishing Group.
Hyperacusis: Over-sensitivity to Sound
ANSD Auditory Neuropathy/Auditory Spectrum Disorder
Cheat Sheet for Reading and Audiogram – What do the symbols / markings mean?