Teaching Students with Sensory Impairments
Definitions, Identification, and Supportive Professionals
Dolly Bhargava, M. Spec. Ed.
Hearing plays an important role in student development and daily performance.
Hearing impairment occurs when there's a problem with or damage to one or
more parts of the hearing mechanism. It is identified as one of the ten most
prevalent causes of disability in the United States. The U.S. Department of
Health and Human Services (1991) reported that five percent of children 18
years and under have a hearing loss. A student with a hearing impairment is part
of a heterogeneous group whose one common characteristic is some degree of
hearing loss. To effectively teach students with hearing impairment, teachers
need to become familiar with hearing related concepts. The purpose of this
chapter is to briefly outline the nature of hearing impairment and provide you with
useful current definitions. The chapter will provide you with information on how
we hear, how hearing is assessed, ways of identifying students with hearing
impairments in the classroom and discuss their learning characteristics. Some
information on the several types of professionals who can be of assistance in
diagnosing and educating students with a hearing impairment will also be
provided.
The Individuals with Disabilities Education Act (IDEA), defines “hearing impairment”
and “deafness” separately. Hearing impairment is defined as an “impairment in
hearing, whether permanent or fluctuating that adversely affects a child’s
educational performance.” Deafness is defined as a “hearing impairment that is so
severe that the child is impaired in processing linguistic information through
hearing, with or without amplification.”
I. Components of the Ear
The organ of hearing is the ear and it is composed of three major parts: the
outer, middle and inner ear. It is important to understand the basic anatomy of
each part and how it works before reading about the different types of hearing
impairments. Refer to
http://www.echalk.co.uk/Science/Biology/InteractiveDiagrams/Ear.htm for a
diagram of the ear. The anatomy and contribution of each part of the ear has
been described below:
Outer ear
Includes the external visible part of the ear (pinna) and the ear canal.
What does it do?
1. Sound waves are received by the pinna from the
…………………………………..environment.
2. Sound waves travel through the ear canal.
3. Sound waves make their way to the beginning of the
middle ear called the ear drum (thin membrane that
separates the outer ear from the middle ear).
(Dugan, 2003; Scheetz, 2000)
Middle ear
Includes the eardrum, ossicles or three tiny bones(hammer/malleus; anvil/incus;
stirrup/stapes) and Eustachian tube.
What does it do?
1. Sound waves reach the eardrum.
2. Ear The ear drum begins to vibrate and makes the
three tiny bones / ossicles to move together.
3. These bones help sound move into the inner ear.
The middle ear is filled with air and for optimal hearing the air pressure inside the
middle ear and outside of the ear needs to be the same. The Eustachian tube
connects the middle ear to the back of the nose. The Eustachian tube helps keeps
the air pressure in the middle ear equal to the air pressure in the environment.
(Dugan, 2003; Fraser, 1996)
Inner ear
Includes a snail-shaped, fluid filled structure called the cochlea, tiny hair cells (cilia)
and the auditory nerve, which travels from the inner ear to the brain.
What does it do?
Some Definitions
1. The vibration of the sound waves causes
the cilia to move.
2. This movement creates electrical impulses or signals
that are sent to the brain via the auditory nerve.
3. The hearing centers in the brain interpret these
signals as sound and help give them meaning.
(Lysons, 2003)
A hearing impairment results when there is a problem in one or more
components of the hearing mechanism. When describing hearing impairment,
three attributes are considered:
1. Type of hearing loss (part of the hearing mechanism that is affected)
2. Degree of hearing loss (range and volume of sounds that are not heard)
3. Configuration (range of pitches or frequencies at which the loss has
occurred).