THE EAR AND HOW IT WORKS

Sound
Sound waves are made when something moves or vibrates The sound can be loud or soft, or low-pitched or high-pitched. The loudness of sound is measured in decibels (dB) and the pitch of sounds is measured in Hertz (Hz).

            The ear is divided into three main sections or parts.  They are the outer ear, the middle ear, and the inner ear.  A diagram has been included for you to see the ear and how it is divided into three sections.

TYPES OF HEARING LOSS

Hearing loss is usually classified as being either conductive or sensorineural, or a combination of both.

Conductive Hearing Loss
            A conductive hearing loss is often the result of an abnormality in the outer or middle ear, a ruptured ear drum, wax build-up in the outer ear, or an infection in the middle ear.  Children who suffer from middle ear infections will often have a conductive hearing loss that fluctuates (changes from day to day).  When treated medically with antibiotics, or possibly surgery, hearing is often restored to normal.  The degree of hearing loss in a child with a conductive hearing loss usually varies from a mild loss to a severe hearing loss.

Sensorineural Hearing Loss

            A sensorineural hearing loss indicates that there is a problem in the inner ear or the auditory nerve which leads to the brain.  This type of hearing loss is usually permanent as damage to the inner ear (cochlea) and nerve endings cannot be repaired.  The degree of hearing loss in a child with a sensorineural hearing loss can vary from a mild loss to a profound hearing loss.
            The cause of a sensorineural hearing loss that occurs before birth is often unknown.  However, some of the potential causes may include infections in the mother such as rubella, toxoplasmosis, and cytomegalovirus, low birth weight in the child, or lack of oxygen to the infant during birthing.  The hearing loss may also be hereditary.  Some children become deafened in the later years of childhood.  Possible causes may include physical trauma to the head or ear area, chronic ear infections left untreated, meningitis, or exposure to excessive noise and loud sounds.

Degree of Hearing Loss

            Hearing loss is generally divided into five categories.  These include mild hearing loss (20-40dB); moderate hearing loss (41-55 dB); moderately severe hearing loss (56-70 dB); severe hearing loss (71-90 dB); and profound hearing loss (91 dB or greater).  In order to understand what these mean, we need to take a look at how we measure or evaluate hearing loss.
          

MEASURING AND EVALUATING A HEARING LOSS

            Sound is generally measured according to the frequency of the sound and the loudness of the sound.

Frequency of Sound

            The frequency or pitch of a sound can very generally be described on a scale as low pitch sounds through to high pitch sounds.  The frequency of sounds is measured in ‘hertz’ (Hz) or cycles per second.  A low frequency sound such as that measured at 250 Hz means that the sound waves travel at a rate of 250 cycles per second (sound waves travel slowly).  A high frequency sound such as that measured at 4000 Hz means that the sound waves travel at a rate of 4000 cycles per second (sound waves travel quickly).  Humans can hear sounds from 20 Hz to 20,000 Hz, but most sounds that we hear for speech are between 500 Hz and 4000 Hz.
            Below you will find an audiogram.  This is probably very similar to the one you received from your doctor or audiologist when your child was diagnosed with a hearing loss.  The numbers across the top of the graph represent the measures of frequency in hertz.  Imagine this scale as keys on a piano – on the left-hand side of the keyboard are the very low, deep sounds.  As you move from left to right, the sound becomes higher and higher in pitch.

Loudness of Sound

            The loudness or intensity of a sound is measured in decibels (dB).  On the audiogram below, you can see that sound is generally measured from 0 to 110 or 120 dB.  ‘O’ represents the quietest sound that usually can be detected by a human ear.  The bigger the number gets, the louder the sound is.  Some sounds are too soft for us to hear and some sounds are so loud that they may hurt our ears.
            The decibel scale is a logarithmic scale.  This means that 20 decibels is ten-times louder than 10 decibels, or that 50 decibels is ten-times louder than 40 decibels.

AUDIOGRAMS

            An audiogram is a graph that is used to show the results of a hearing test.  The graph will show hearing levels for the right ear and the left ear.  This means that the audiologist has tested your child’s hearing and has indicated on the graph the decibel level at which your child is able to detect a sound at different frequencies.  The audiologist will have tested your child’s hearing levels in decibels over a range of different frequencies.

How to Read an Audiogram

• The numbers across the top of the graph show the frequency or pitch of sounds. 
• The numbers along the side of the graph show the decibel or loudness levels of sound.
• The pictures and letters show you the loudness and pitch of sounds in our environment and sounds in our speech.
• The degrees or amounts of hearing loss are shown on the right side of the chart.

For many of you reading this manual, you will have already received the diagnosis that your child is deaf.  Many of you will already have begun to experience the painful feelings of uncertainty and disbelief that many parents in this situation experience.

What you may be feeling
            You are not alone and the feelings you may be experiencing are very common among families in your situation.  Throughout pregnancy and the early days of bonding with your child you may have thought or expressed your dreams and wishes for your child.  You may have felt comfort in knowing where your child will go to school, some potential friends and sports and activities, as well as the trips you will take as a family.  Those thoughts, wishes, and dreams may now have been replaced with feelings of uncertainty and hundreds of questions that seem to shadow your dreams.  Issues such as communicating with your own child, language development, academic development, and social development may be foremost on your mind.

Coping with your feelings

            First and foremost, many parents report that in order to deal with their feelings, they must allow themselves the opportunity to grieve.  Grieving is a natural and normal expression of emotions.  You may at times choose to grieve alone, or express your grief by talking with someone.
            Throughout this time it is important that you all feel supported.  People may seek out support in different ways, feel supported in different ways, and offer support in different ways.  Perhaps one of the most valuable supports to you as parents of a newly diagnosed deaf child is the support that can be offered by other parents of deaf children.  These parents have experienced the roller-coaster of feelings and emotions that you are experiencing and they have contemplated the issues that you are contemplating.  Many people choose to seek support from family members or friends.  Some will seek support from professionals in the field of deafness, particularly doctors and educators.  Counselors and Family Support Workers are also available to families of newly diagnosed deaf children.
            As a family living in the Okanagan Valley of BC, you face a challenge in accessing services related to raising a deaf child.  Thus it becomes even more important for you to make contact with other families of deaf children in the area.  These families can support you in many ways.  They will be knowledgeable about accessing services in your area as well as services from the Vancouver or Edmonton areas.  They may offer you the opportunity to talk about your feelings and share some of the ups and downs of their own experiences so far.  Dads can get together and discuss their own unique feelings, questions, or concerns (separate from mom!).  Siblings may also feel comfort in talking with other siblings of a deaf child,
           Contact your local Teacher of the Deaf,  the Canadian Hard of Hearing Association Parents Branch or Family Network for Deaf Children to establish contacts with other families.

VISITING THE AUDIOLOGIST

WHAT TO EXPECT

Interior Health Unit (Vernon) Audiology Department

            You may or may not have already experienced a visit to the audiologist.  In either case, the following are some helpful hints and suggestions on how to prepare for your visit, what to expect during your visit and some questions you may want to ask your audiologist.
            Visiting an audiologist for an audiological evaluation involves more than testing your child’s ability to hear sounds.  Your visit may include:

• Gathering a Case History – The audiologist may ask you questions regarding the birth and development of your child, how you began to detect a hearing loss in your child, when and how the hearing loss was diagnosed, medical history of your child, family history of hearing loss, and questions regarding your observations of your child’s speech and language development.

• Physical Examination – The audiologist may look inside your child’s ears with an instrument called an otoscope.  He or she will be looking for any signs of infection in the ear, tears in the eardrum, excessive wax build-up, or any objects inside the ear that should not be there, such as food or toys.

• Testing Hearing – Your child’s hearing will be tested in a soundproof booth.  It is a special room with speakers, earphones, and boxes of toys that move and light up.  You may stay with your child in the sound booth, and an audiometric technician may also be in the room with you.  The audiologist will sit behind a window in another room.  The audiologist will use a machine called an audiometer to produce sounds at different loudness and frequency levels.  Throughout the hearing test, the loudness of the sound will gradually be turned down.  The audiologist will be trying to determine the quietest sound that your child can hear.  The quietest level at which your child can hear is called the “hearing threshold”.  These levels may be different in the right and left ears, and for low-pitched sounds and high-pitched sounds.  Audiologists are specially trained to do hearing tests on all ages of children, even very young infants and toddlers. 

• Types of Hearing Tests – Your child may need different types of hearing tests.

Air Conduction hearing tests are done through speakers or headphones by sending sound waves through the air.

Bone Conduction hearing tests are done by placing a special headset that vibrates on the bone behind the ear.

These two tests are important in helping the audiologist identify whether your child has a conductive or a sensorineural hearing loss.  If your child can hear better with the bone conduction test, then your child could have a conductive hearing loss.  If your child’s hearing is the same with the bone conduction and the air conduction tests, then your child’s hearing loss is a sensorineural hearing loss.

Speech Audiometry and Word Recognition tests may also be done as part of your child’s hearing evaluation.  Because the other tests use only tones to test your child’s hearing, it is also important to evaluate the levels at which your child can identify spoken words.  Single-syllable and two-syllable words may be used in this test.  The words may be presented in a quiet environment and also with background noise in the room.

Auditory Brainstem Response Testing (ABR) may be used if your child is too young to participate in other hearing tests.  It is best if your child is sleeping for this test.  This test measures how the brain responds to sound.  For more information on this type of testing, see the brochure at the end of this chapter or contact your local audiologist.

• Testing the Functioning of the Ear – Two types of tests will usually be done to check how the ear is working. 

Impedance Testing is a test of the functioning of the middle ear.  This kind of testing will help to check for infection in the middle ear as well as to see if the muscles of the middle ear are working correctly.  A puff of air is put into the ear and the audiologist can then measure if the eardrum is moving normally.  A similar test with loud sounds may also be done to measure the reflex abilities of the middle ear muscles.

Otoacoustic Emissions Testing is a test to see if the hairs inside the cochlea are working properly.  Your child will hear sounds and clicks and the machine will measure the response of the hairs inside the cochlea.

            After conducting these tests, your audiologist will discuss the results with you and may refer you to other specialists depending on their findings.  Be sure to ask your Audiologist for a copy of your child’s audiogram!

GLOSSARY OF TERMS

Audiogram – A graph used to record the results of a persons hearing test.  Results will show how loud a sound must be before the person is able to hear it.  The sound is measured according to pitch (frequency) and loudness (decibel) level.  The instrument used to test a persons hearing is called an audiometer.

Audiologist – A specialist whose role is to measure and identify hearing – also assists in the rehabilitation of persons with a hearing loss.

Audiometric Technician – Assists the Audiologist in hearing tests and is the contact person for the aftercare of hearing aids including repairs, ear-molds, or other technological questions.  The technician will also refer persons to the Audiologist when
necessary.

            Your family doctor or audiologist may refer you to other specialists in the field of hearing.  Families living in the Okanagan may have to travel to Alberta or the Lower Mainland area to receive special medical services for your child.

BC Children’s Hospital
4480 Oak Street    
Vancouver, BC  V6H 3V4
(604)875-2345

Glenrose Rehabilitation Hospital
10230 – 111 Ave.    
Edmonton, AB  T5G 0B7
(780) 471-2262   Fax: (780) 471-7976

Sunny Hill Health Centre for Children
3644 Slocan Street 
Vancouver, BC   V5M 3E8
(604) 434-1331  TTY (604) 436-6515
Fax (604) 436-1743   

The Sunny Hill Health Centre provides special services to children and their families from all across British Columbia who have physical and developmental disabilities.

            The Hearing Resource Team at Sunny Hill is set up to provide services especially for children with a hearing loss and their families.  There may be many people involved with the team, depending on your child’s particular needs.  The following is a list of people who may be involved in your child’s hearing resource team:

Audiologist – Specialist in the identification, measurement, and rehabilitation of hearing loss.

Clinical Nurse Specialist – A nurse specializing in the field of deafness and hearing loss.  Often this nurse will work with individual families helping them adjust to the recent diagnosis of hearing loss.

Developmental Pediatrician – A doctor specializing in the area of infant and child physical and mental development.

Occupational Therapist – Provides assessment and treatment to persons with physical challenges related to the performance of daily activities.

Ophthalmologist – A doctor specializing in the functions and diseases of the eye.

Otolaryngologist – A doctor specializing in the functions and diseases of the ear, nose, and throat.  (Ear, Nose & Throat Specialist)

Otologist – A doctor specializing in the functions and diseases of the ear.

Physiotherapist – A specialist in the area of physical rehabilitation and therapy.

Psychiatrist – A doctor specializing in the treatment of mental disorders.

Psychologist – A specialist in mental processes and its effect on behaviour.

Social Worker – An employee of the Ministry of Children and Families that counsels children and their families.

Speech & Language Pathologist – A specialist who designs and implements programs to improve the communication skills of persons with speech impairments.

For more information about the services that Sunny Hill Health Centre offers, see their information under the Services section of this website.

LANGUAGE & COMMUNICATION

            Upon receiving the diagnosis of deafness in your child, you may have felt overwhelmed with questions and concerns regarding the development of language, communication, and speech in your child.  The issues around language and communication development with deaf children probably involve the most complex, difficult decisions that families and educators will encounter.

            Some of the questions that many parents find themselves contemplating include:

• How will I communicate with my child?
• How will other people communicate with my child?
• Will my child learn English? What language will my child learn?
• How will a deaf child learn English?
• Will my child learn to speak?
• How will my child learn to read without hearing?
• Will my child learn sign language?
• How long will it take for my child to learn sign language?
• Will my child have to go to a special school? Will we have to move?
• Will my child have friends?

There are several major factors that may affect a deaf or hard of hearing child’s potential for language development, growth, and learning.

Consider these factors for your own deaf child:

• The age of onset of the hearing loss

At what age did your child’s hearing loss occur?
           

• The age of diagnosis of the hearing loss

How old was your child when the diagnosis of a hearing loss was confirmed?
Does this differ from the age at which the hearing loss occurred?

• The degree of hearing loss

What is the amount of hearing loss that your child has?

Is it the same in both ears?                                                                                   

• The use of amplification

Does your child receive any benefit from the use of hearing aids?
At what age were hearing aids first attempted?
How long after your child’s hearing loss occurred were hearing aids attempted?

• The type of hearing loss

Is your child’s hearing loss a conductive loss (in the middle ear), sensorineural loss (in the inner ear), or a mixed hearing loss (a combination of both)?

• The etiology of the hearing loss

What is the cause of your child’s hearing loss (may be unknown)?

• Other medical factors

Does your child have any other medical conditions (physical or intellectual) in addition to the hearing loss?

All of these factors will have implications for your child's social, emotional, and intellectual growth. Identifying these characteristics will help you and other hearing professionals develop a plan to best meet the developmental needs of your individual child.

LANGUAGE DEVELOPMENT AND DEAF CHILDREN

Children with normal hearing and normal development in other areas will acquire language very naturally.  That is, they do not have to work at it.  They learn language without being formally taught.  They interact with their world and the people in their world using all of their senses.  They interact directly with individuals and groups of people and thus learn the connections between words and meanings to organize their world.  Hearing children also have the special opportunity to be exposed to language through the ambient communication that is around them and not directly spoken to them.  For example, hearing children will overhear the conversations of other adults, children, news on the radio or television and learn from the experiences and conversations of others. Language learning is then a very natural process for those hearing children.
Deaf children do not have the same opportunities for language development.  They are not able to 'overhear' the conversations of others, the radio, the television, and when born to hearing families, are often limited in the number of people they communicate with.  Deaf children cannot access spoken language in a natural way.  Some deaf children are able to learn spoken English with the use of hearing aids and other amplification devices, but for these children, spoken English becomes a skill that must be directly taught rather than naturally acquired.

Many people often mistake spoken English as being language.  They believe that if a child cannot speak, then they do not have a language.  Speaking is a way of communicating one's ideas, feelings, and thoughts.  Speech is simply the tool that we, as hearing people, use to express ourselves.  Speech is not the only means of communicating our thoughts.  Deaf people communicate their thoughts by using sign language.
If your child's deafness occurred before the age of three, your child is considered to be 'prelingually deaf', that is, he or she became deaf before spoken language was acquired.  If your child's deafness occurred after the age of three, your child is considered to be 'post-lingually deaf', that is he or she became deaf after acquiring spoken language.  A hearing child begins acquiring language from birth.  The age at which your child became deaf may have implications for your child's language development.

Although many deaf children do learn to speak, not all deaf children will be capable of learning speech to the extent that it is useful for them in communicating their ideas, feelings, and thoughts.  Many of the factors discussed above, such as the age at which your child became deaf, the degree of hearing loss, and potential benefit from amplification, will impact on your child's ability to learn spoken language.  You should discuss these factors with your audiologist, other hearing professionals such as an early childhood educator or a teacher that specializes in working with deaf children, or a Deaf adult who has speech skills.

In BC and the rest of North America, the majority of deaf persons who use sign language to communicate, use American Sign Language (ASL).  American Sign Language is an official language and it is the accepted mode of communication by Deaf persons.  American Sigh Language, or ASL for short, is a. part of Deaf culture.  It is a growing, living language. ASL is a visual-gestural language.  Words and ideas are communicated according to the location, movement, and shape of the hands as well as various eye" head, body, and facial movements. Because all of the information is communicated visually through the air, ASL is completely accessible to a deaf person. Studies have shown that when a deaf child is born to deaf parents, that child will develop language in the same developmental progression as hearing children born to hearing parents.

            This is perhaps one of the most difficult decisions that families face in raising a deaf child.  Families often make this decision based on the needs and abilities of their
deaf child, as well as the needs of the other family members. Your child's needs and abilities may change over time and so may your decision about which communication method is best method is best for your child.  Many children are able to learn both-speech and sign. Many parents often feel frustrated when choosing among communication methods.  You may read books and articles, or talk to other deaf adults or professionals in the field of hearing and deafness who may offer different advice and perspectives as to what they feel to be the best choice for your child.  This often leaves parents feeling confused and frustrated as they seek out answers, only to find that there are more questions than answers available.  As your child grows and develops it will become increasingly important for you to monitor your child's progress and development in the communication method you have chosen.  Talk to other parents who have made similar choices, and talk to parents who chose alternate communication options.  It is important to remain flexible and open.  The more you observe your child, the more familiar you will become with your child's strengths and abilities, and the easier your decisions will become.

Historically, the education of deaf children has been filled with controversy over the best method of communication to use in raising and educating these children.  Various methods have been introduced and practiced.  Generally, there are two methods -the manual method (use of sign languages) or the oral method (the use of speech and hearing skills only).  There is not anyone method that is best for all deaf children.  Each deaf child is unique and has individual strengths and abilities depending on the factors discussed above.  Yet, the controversy still continues today as to the best approaches and methods to use in raising and educating deaf children.  The following is a list of the most common methods available for communicating with deaf children and a brief description of each:

American Sign Language
ASL is a visual-gestural language used by Deaf/deaf people all across B.C. and North America. It is the official sign language used by Deaf persons and is an official language in itself.  The words, intonation, and grammar of the language are conveyed through the movement, location, and shape of the hands, face, arms, and body. ASL has its own The words, intonation, and grammar of the language are conveyed through the movement, location, and shape of the hands, face, arms, and body. ASL has its own grammatical structure just as other languages such as French or German.

Cued Speech
This is a system that uses hand cues in addition to speech/lip-reading to help make the speech more visible.  The cues do not have meaning but when used with speech will enhance a person’s ability to read speech on the lips by representing the sounds of consonants and vowels.

Fingerspelling
Not all words or meanings can always be interpreted in sign languages such as ASL. Fingerspelling (each letter of the alphabet is represented with a handshape) is used in both Signed English and ASL and may be used alone or together with it's sign counterpart. Often people will use fingerspelling for the names of people and places or when a new sign is being introduced.

Oral/Aural Method
This method focuses on the use of any hearing that the child may have, particularly with the use of hearing aids or other assistive hearing devices, as well as the development of speech and lip-reading skills.

Pidgin Sign English
A combination of ASL and Signed English signs are used often in English word order.

Signed English
This is a form of sign language that is usually used together with spoken English.  The signs represent English words and are conveyed in English word order.  Special signs have been developed to show English markers such as in word endings -s, -ing, -ed.  Signed English is not a language; rather, it is a system used to represent spoken english.

Total Communication
This is a philosophy of communication rather than a method of communication. It combines aspects of many methods of communication such as speech, lip-reading, manual sign languages, fingerspelling, and the use of any hearing that a deaf child may have.

You are now aware that several communication options are available to you, your family, and most of all, your deaf child.  Choosing an option and developing communication skills in that method can be a confusing and frustrating process.  There are professionals in the field of hearing and deafness who are available to you to help you make a decision that you and your family are comfortable with and to help you develop the necessary skills in that area.
The Services Section of this website will provide you with information regarding the supports and services that are available to you and your family in making communication choices as well as educational placement decisions when your child becomes of school age.  The agencies that are available may offer different perspectives and ideas about how best to raise and educate your deaf child.  You are encouraged to explore all of the options, meet with professionals from various agencies, and listen to all of the opinions expressed.  Empower yourself with the knowledge and information that you feel you need to make a decision that you are comfortable with in meeting the unique needs of your deaf child.