MINIMAL HEARING LOSS

EFFECTS OF MINIMAL HEARING LOSS ON STUDENT PERFORMANCE IN THE CLASSROOM

ONE OUT OF EVERY FOUR STUDENTS WILL HAVE A LOSS

Childhood hearing loss is a very common problem within our schools. There are an estimated 8 million children in North America who have some degree of hearing loss. Even a very mild loss can affect how a student learns. Every teacher in the early elementary school can expect to have one-fourth to one-third of his or her students without normal hearing on any given day. Children spend at least 45% of their day engaged in active listening activities. It is obvious that teachers need to be aware of the impact such a loss can have on learning.

empty classroom noisy classroom

Figure 1 Figure 2

The maximum desirable noise level for children having normal hearing is 35 decibels (dB). The noise level can reach up to 44 decibels in an empty classroom with only traffic noise from the street or hallways (Fig 1).
With 25 students and one teacher, the noise level can reach from 55-75 dB (Fig. 2).

Click here for an example of a typical classroom.

What is a decibel?

audiogram To understand about hearing loss you need to know some basic information about how hearing is measured. Audiologists use an audiogram to plot responses to sounds (Fig 3).

The yellow area represents all the sounds that make up speech.

Figure 3

hertz

Vertical lines on an audiogram represent pitch or frequency measured in Hertz (Hz). Pitch ranges from very low sounds on the left to very high sounds on the right (Fig.4).

           Figure 4

decibel
The horizontal lines represent loudness or intensity measured in decibels (dB). Loudness ranges from very soft at the top to very loud at the bottom (Fig. 5).

               Figure 5

normal hearing Normal hearing for children ranges from 0-20 decibels in all frequencies. ( Fig 6).

           Figure 6

Children in the process of building their language base do not have the same linguistic experience as adults. Adults call on their experience with language (previous knowledge of a topic, known vocabulary, grammatical/sentence structures) to fill in the gaps in hearing. It is only when children reach their teens that their speech recognition in difficult listening conditions comes close to that of an adult.

What causes minimal hearing loss?

Otitis Media

Ear infection or otitis media (OM) is the most frequent medical diagnosis for children. OM is an inflammation in the middle ear that usually causes fluctuating hearing loss averaging 21-40dB. The National Center for Health Care Statistics estimates 70 cases in every 100 children under 5 years old. It ranks second to the common cold in preschool children. Many children with a loss due to OM will pass a school screening test. It is not diagnosed 50% of the time.

Almost all children have one episode by age six
63% have a recurrence
96% have OM in the first year of life
85% have OM in the first six months

An estimated 5 million days are missed every year due to otitis media. When a child has OM, the fluid that arises takes an average of 40 days to be absorbed or drain. If a child has chronic OM (4-5 episodes over a 6-12 month period), he/she could experience a possible 200 days of reduced hearing in a year. 30% of students with learning disabilities have histories of chronic middle ear problems.

Click here for an example of a loss due to otitis media.

Sensorineural Loss

2% of children have a permanent loss from damage to the inner ear/auditory nerve due to illness, heredity, head trauma, complications of birth and other causes. Sensorineural losses often cause damage to the high frequency regions of hearing resulting in a muffled sound-to-speech ratio and reducing speech understanding.

Click here for an example of a sensorineual loss.

Effects on Learning

Hearing loss can cause significant emotional and social problems. It also has a negative impact on verbal language, reading, writing and academic performance. A loss of any type or degree can present a barrier to incidental learning:

90% of the knowledge acquired by a young child is learned incidentally
a hearing loss is a barrier to overhearing and learning from the environment
children with a loss often miss social clues
children with a loss cannot listen and learn--at least 10% of classroom instruction may be missed

Academic losses occur in children as early as kindergarten and first grade. Most children with losses begin to show considerable learning difficulties when they reach third grade. This difficulty may be due to the changes in language complexity, less visual clues, more verbalizations. greater need to sequence and recall, and lack of development of preskills in the previous grades.

Often the symptoms of a hearing loss are mistaken for an Attention Deficit problem. The chart below shows the similarities.

Similarities Between
Mild Hearing Loss &
Attention Deficit Disorder

MILD HEARING LOSS	ATTENTION DEFICIT DISORDER
Inappropriate responses	Blurting out answers before questions are completed
Difficulty following directions	Difficulty following through on instructions and organizing tasks
Difficulty sustaining attention during oral presentations	Difficulty in listening to others without being distracted or interupting
Impulsive	Acts on the spur of the moment
Frequently asks for repetition	Focuses only with frequent reinforcement or is under very strict control
Academic failure	Multiple problems with schoolwork and social activities
Poor self-concept	Isolated and low self esteem
Doesn't complete assignments	Frequently fails to finish schoolwork, or works carelessly
Doesn't seem to listen	"Can't sit still and listen!"

chart courtesy of Phonic Ear

How teachers can help

Teachers need to evaluate the listening environment and the skills of their students. Suggestions for assessment tools to evaluate are: Listening Environment Profile, Screening Instrument for Targeting Educational Risk (SIFTER), and Evaluation of children with Suspected Listening Difficulties.

Suggestions to aid in meeting the specific needs of the hearing impaired child in the classroom are:

Do not turn away to write on the board or cover your mouth while talking
Rephrase if the child does not understand rather than repeat the same words over and over.
Seat the child away from heating/cooling systems, hallways, playground noise, etc.
Allow the child to move around in the room in order to clearly see the speaker
Use as many verbal cues as possible. Take time to explain things. Give context clues-- a written word, object or picture to set the stage to help follow the change of subject
Write key words of an idea or lesson on the board or use an overhead
Assignments should be written on the board so that the student can copy them into a notebook used for this purpose
Appoint a helper/notetaker for the child
If the child's hearing impairment involves only one ear or if the impairment is greater in one ear than the other, seat the child in front of the room with his poorer ear towards the noisy classroom and his better ear towards the teacher
Speak clearly and with moderate speed

Use of Assistive Devices

The introduction of FM systems into the classroom has had a significant impact on student learning. Numerous studies have shown improvement in attention, understanding directions, classroom participation and school behavior. Amplification equipment is meant to enhance the acoustical accessibility to teacher instruction to all children by: increasing the overall level of the teacher's speech, substantially improving the speech-to-noise ratio, and producing a uniform speech level in the classroom that is unaffected by teacher or pupil position.

There are two common types of FM systems:

1. Personal FM: reduces distractions from excessive noise by producing a direct transmission of speech through an individual student's system. Students are required to wear receivers and headphones

2. Freefield System: 2-4 speakers are mounted on the wall and the teacher wears a microphone that amplifies voice 10-12dB above room noise.

Students using the soundfield system have shown:

An 12% average improvement on vocabulary test scores
Improvement in means spelling scores--3^rd grade 14.5%, 4^th grade 9%, 5^th grade 22.4%
Significant improvement in Scholastic Reading Achievement Scores

Many children with hearing loss might be eligible to receive services through Section 504. Section 504 covers children who do not meet the eligibility criteria for special education, but still do not have access to a "free and appropriate public education" (FAPE) because of a disability. If a child is serviced trhough 504, school districts might be obligated to use regular education funds to provide services or accommodations.

The Individuals with Disabilities Act (IDEA), mandates that special education and related services are to be provided through an Individual Education Plan (IEP)

Children identified by both laws could be eligible for purchase of auditory equipment. Phonic Ear provides a nice guideline on how to write a Sound Field Funding Proposal.

Conclusion

I hope this information has been a useful resource for you. If you have any questions or comments please
email me

For further information, please go to the following sites:

Understanding Your Audiogram

How to Read Your Hearing Test

Impact of Hearing Loss on Children in Typical School Environments

Canadian Hearing Society

Phonic Ear

Hear More: Classroom Amplification System

Where do we go from Hear?

DeafWeb

A Little Hearing Goes A Long Way

Gallaudet University

Alexander Graham Bell Association for the Deaf

	To understand about hearing loss you need to know some basic information about how hearing is measured. Audiologists use an audiogram to plot responses to sounds (Fig 3). The yellow area represents all the sounds that make up speech.
Figure 3

	The horizontal lines represent loudness or intensity measured in decibels (dB). Loudness ranges from very soft at the top to very loud at the bottom (Fig. 5).
Figure 5

	Normal hearing for children ranges from 0-20 decibels in all frequencies. ( Fig 6).
Figure 6