Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Evolution of mammalian auditory ossicles wikipedia , lookup
Telecommunications relay service wikipedia , lookup
Hearing aid wikipedia , lookup
Hearing loss wikipedia , lookup
Noise-induced hearing loss wikipedia , lookup
Sensorineural hearing loss wikipedia , lookup
Audiology and hearing health professionals in developed and developing countries wikipedia , lookup
Child Hearing Loss 3 Child Hearing Loss Overview/Definition of the Disorder Hearing loss is an invisible condition that results in communication problems that can ultimately interfere with learning and social development (Nelson, 1997). It is becoming a widespread problem for a significant amount of children. Stedman’s Medical Dictionary defines hearing loss and hearing impairment as “a reduction in the ability to perceive sound; may range from slight to complete deafness” (1990). Sound is measured by its frequency and its loudness. Hearing loss occurs when impairments occur in either area or both. The tool to measure your hearing is an audiogram, which plots an individual’s response to sounds as shown in Figure 1. In a sense an audiogram is a picture of you hearing. The vertical lines represent the pitch, which is measured in Hertz. The pitches move from the lowest pitch to the left and the highest pitch to the right. The most important pitches would there for be in the middle around 500 Hz to 2000 Hz. The horizontal lines represent loudness, which is measured in decibels. The ranges are measured from the top down (Mehr, 2001). Normal hearing for children ranges from 0-20 decibels in all frequencies. Figure 1. Child Hearing Loss 4 Hearing loss is separated in two different categories. First there are congenital causes and second there is acquired hearing loss. Congenital hearing loss that exists or dates from birth and Acquired is hearing loss which appears after birth, at any time in one's life, perhaps as a result of a disease, a condition, or an injury (ASHA, 2004). Acquired hearing loss would also fall in the same field as conductive hearing loss. This hearing loss occurs when the construction pathway which are the either the middle or outer ear have problems transmitting sounds to the inner ear. This type of hearing loss does not result in severe hearing disabilities (NICHCY, 2004). The number one causes of hearing loss in the conductive category are ear infections, which in medical terms is called Otitis Media. The National Center for Health Care Statistics estimates that annually there are 70 OM cases for every 100 children under the age of 5 years (Nelson,1997). An infection from fluid in the middle ear (right behind the eardrum) is the cause of Otitis Media. In most causes these ear infections will clear up on their own or with the help of a doctor’s prescription of antibiotics (Mehr, 2001). Rarely do these infections cause permanent damage to the eardrums of long term hearing loss. However when otitis media does occur over again, damage to the eardrum, the bones of the ear, or even the nerve can occur and cause permanent sensorineural hearing loss. Meningtitis is an acquired hearing loss. Meningitis is an inflammation in the lining of the brain. Hearing loss can occur from actually result of the infection or the body’s response to the infection. Measles and mumps can cause viral infections to the auditory nerve Congenital Hearing can result from genetic factors or prenatal defects at or during birth. There are three types of genetics factors: auto dominant, auto recessive, and x- Child Hearing Loss 5 linked hearing. Auto dominant means that if one parent has the dominant gene of hearing loss than there is a 50% chance that child will be affected. Auto recessive mean that if both parents carry the recessive gene of hearing loss than there will be a 25% chance of the child to experience hearing loss. X-linked hearing is completely sex related. A mother could carry a recessive trait for hearing loss on the sex chromosomes and pass it t her male children (ASHA, 2004). Prenatal complications can harm a child’s hearing. Premature births can cause a child not to able to form the little bones in is ear or other essential growth parts. Sexually transmitted diseases like syphilis and herpes can also be transmitted to the child through the birthing procedure. These diseases can also be a cause of hearing loss. Characteristics If a child is diagnosed with hearing loss that does not mean that the child is deaf. There are varying degrees of hearing loss. These degrees range from mild to severe hearing. Kluwin and Stinson (2001) did a longitudinal study of the deaf students in public schools. After their study they were able to label the deaf students in one of four different hearing loss classifications. The first group was a collection of students who depicted moderate hearing loss. This category of students portrayed above average grades, intelligible speech and did not need the assistance of an interpreter. These students were able to function well independently. There moderate hearing loss did not affect them. The second group was a collection of students who depicted a more severe hearing loss. These students still read on the same grade level and had comprehendible speech but were helped with assistive listening devices or and interpreter. The third group was a collection of students who were profoundly deaf. These students read below Child Hearing Loss 6 the grade level. Though they will use speech when appropriate they prefer to sign instead. The last group was a collection of students who suffered the severest hearing loss. These students read considerably below the grade level and prefer pointing and grunting as a source of communication. Discrepancy in these four types occurs when background information of the child is brought into the picture. For example a student’s race or economic situation may be a major factor. A lower income family may not have the necessary funds to help their child who is in group two and as a result their child’s hearing loss might worsen and the child will be moved to group three. Also it is very common for a child labeled in group four to have very poor family support. These students might have families that have not adjusted or responded to the diagnosis of hearing loss (Kluwin and Stinson, 2001). The way a child performs in school may also result in the different communication philosophies, friendship patterns, and history of placement situations. The age at the onset of deafness, the age of the diagnosis of the child’s hearing loss, the availability of early services and the families responses to those services could also be school performance factors (Kluwin & Stinson, 2001). There are three main characteristics of hearing loss, language communication, psychosocial dimensions, and education (Turnball, 2004). Children who experience hearing loss tend to communicate either using oral/aural, simultaneous or American Sign Language communication. These children with hearing loss have to develop unique communication skills through their eyes rather than their ears. Oral/aural communication is communication in spoken English through the use of speech, speech reading, residual hearing, and amplification of sound (Turnball, Child Hearing Loss 7 2004). American Sign Language is the primary language used in the United States for the hard of hearing or deaf individuals. In sign language, facial expression including the raising or lowering of the eyebrows while signing and body language are integral parts of communicating. These actions help give meaning to what is being signed, much like vocal tones and inflections give meaning to spoken words (Sternberg, 1994). Simultaneous communication uses the components or both oral/aural communication and American Sign Language together. A child’s emotional and social personality can be highly affected and suffer if communication is a problem. In most cases children who suffer from hearing loss have parents whom are not deaf. These hearing parents find it very difficult to communicate with their children. This communication problem becomes a roadblock for the parents by not being able to fundamentally teach their children and give them positive interaction (Turnball, 2004). If communication between peers and teachers is partial and incomplete then this can affect a child’s ability to be part of a social group and develop a positive self-image. With out good communication a child can be in the dark about the different social norms, rules of conversation and appropriate ways to respond to certain situations (Turnball, 2004). Turnball cut the last characteristic of hearing loss, education, into two major concerns (2004). The first issue was whether they should put students in inclusion of a regular classroom of if the students should be segregated in deaf-only classrooms. The second issue is the performance level of non-white deaf students. Turnball concludes that hearing loss students perform at different levels than normal hearing students. Statistics of Hearing Loss Child Hearing Loss 8 After numerous studies and reports statistics have shown that: Everyday in the United States, approximately 1 in 1,000 newborns (or 33 babies every day) is born profoundly deaf with another 2-3 out of 1,000 babies born with partial hearing loss, making hearing loss the number one birth defect in America (Hearing Loss Organization). Males of all ages are more likely to suffer from hearing loss than women (National Academy on an Aging Society, 1999). When children are not identified and do not receive early intervention, special education for a child with hearing loss costs schools an additional $420,000, and has a lifetime cost of approximately $1 million per individual (Hearing Loss Organization). Whites are more likely to suffer from hearing loss than blacks (National Academy on an Aging Society, 1999) Families with lower incomes are more likely to suffer from hearing loss than higher income families (National Academy on an Aging Society, 1999). Of the 12,000 babies in the United States born annually with some form of hearing loss, only half exhibit a risk factor – meaning that if only high-risk infants are screened, half of the infants with some form of hearing loss will not be tested and identified. In actual implementation, risk-based newborn hearing screening programs identify only 10-20% of infants with hearing loss. When hearing loss is detected beyond the first few months of life, the most critical time for stimulating the auditory Child Hearing Loss 9 pathways to hearing centers of the brain may be lost, significantly delaying speech and language development (Hearing Loss Organization) Only 69% of babies are now screened for hearing loss before 1 month of age (up from only 22% in 1998). Of the babies screened, only 56% who needed diagnostic evaluations actually received them by 3 months of age. Moreover, only 53% of those diagnosed with hearing loss were enrolled in early intervention programs by 6 months of age (Hearing Loss Organization). African American and Hispanic students who are hard of hearing of deaf perform significantly lower on measures of achievement compared to their white, non-Hispanic peers who are hard of hear or deaf. Educational Issues Having any type of hearing loss will not affect a student’s ability to learn or take in education. Children that are hard of hearing or deaf though will find that is extremely difficult to learn vocabulary, grammar, word order, idiomatic expressions, and other aspects of verbal communication (NICHCY, 2004). Every teacher in the United States should expect at least one-third of the classroom to be hearing impaired. This creates a problem in teaching when most normal hearing students spend about forty-five percent of their day engaged in active listening activities (Mehr, 2001). Hearing loss can cause significant educational and social problems. Some children experience academic delays and miss school due to hearing loss problems. Most classrooms are very noisy, which interferes with all children’s performance. The noise can affect speech and understanding of children with hearing loss. Child Hearing Loss 10 Hearing loss can cause a barrier to accidental learning. Young children’s learning is about ninety percent accidental (Mehr, 2001). Children miss important socials from not being able to overhear conversations. Around the third grade is about the age that students with hearing loss problems start to fall behind compared to the rest of their normal hearing peers. This may be due to the changes in language complexity, less visual cues, and more verbalizations. One major educational issue is that students with hearing loss are misdiagnosed with Attention Deficit Disorder. Inconsequently these two disorders share very similar characteristics. Figure 2 shows similarities between mild hearing loss and Attention Deficit Disorder. ATTENTION DEFICIT MILD HEARING DISORDER LOSS 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 interrupting Impulsive Frequently asks for repetition Academic failure Acts on the spur of the moment Focuses only with frequent reinforcement or is under very strict control 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 Figure 2. (Mehr, 2001) "Can't sit still and listen!" Under the Individuals with Disabilities Education Act (IDEA) every child with a disability is guaranteed a free and appropriate education under federal law. Hearing Child Hearing Loss 11 impairment and deafness fall under two of the categories of IDEA in which children with those disabilities may be eligible for special education and related services (NICHCY, 2004). As mentioned earlier in this paper the placement of where students with hearing loss get their educational learning is very controversial. In the IDEA law it states that students should be placed in the least restrictive environment. In other words educational placements that will help them advance to higher levels of education. This definition is could either mean a regular classroom for some or a private, restricted classroom from others. Every child should go through an Individual Educational Plan (IEP) that will determine where the child should be placed to best benefits his or her goals. Treatments Early intervention is the key to academic success for hearing loss students. It is important to diagnose a hearing loss as early as possible so that early intervention services can begin before 6 months of age. Early intervention can take many forms, such as getting children fitted for hearing aids, providing counseling and support for parents, and teaching parents how to stimulate speech and language in their child (AAO-HNS, 2002). The treatment of hearing loss all depends on the severity of the child’s disorder. With most causes of Otitis Media doctors can prescribe medications. Hearing aids are probably one of the more known about treatments. Hearing aids though do not cure hearing loss they just help make sounds louder which in return help a student hear better. A hearing aid is powered by a battery and operates by picking up sound, magnifying its energy and delivering this amplified sound to a child’s ear. The use of cochlear implants have had a dramatic impact on the linguistic competence of the profoundly hearing Child Hearing Loss 12 impaired children (Geers, Nicholas, and Sedey, 2003). A cochlear implant is an electronic device that compensates for the damaged or absent hair cells in the cochlea by stimulating the auditory nerve fibers (Turnball, 2004). The implant has two parts an, internal and external part as shown in Figure 3. The internal part is surgically placed inside the ear where the cochlear is. The external part is worn like a regular hearing aid. The literature on language development in children who use cochlear implants develop language at a faster rate than children with similar degrees of hearing loss who use just hearing aids (Geers, Nicholas, & Sedey, 2003). Figure 3 Assistive listening devices are amplification equipment that are meant to enhance the acoustical accessibility of the teachers instructions to all the children by: increasing the overall level of the teachers speech, substantially improving the speech-to-noise ratio, and producing a uniform speech level in the classroom that is unaffected by the teacher or the pupil position (Mehr, 2001). One of the newer assistive listening devices is the frequency modulation system. Students using assistive listening devices have shown a twelve percent average improvement on their vocabulary scores and significant improvement in Schlastic Reading Achievement Scores (Geers, Nicholas, and Sedey, 2003). Interpreters are often used in school to transmit spoken English to sign language. These are qualified professionals that serve as a link between a teacher and the student. There are two types of interpreters, oral and cued speech. Oral interpreters’ mouth Child Hearing Loss 13 speech to students using facial expressions and cued speech interpreters mouth the words to students and use hand signs (AAO-HNS, 2002). Captioning also helps a student to learn by being able to read the words of what is being said. Caption videos can have English subtitles printed across the screen. C-Print Captioning is a speech to print system in which a hearing captionist (transcriber) types the words of the teacher and the other students as they are being spoken in to a laptop computer. Helpful websites and organizations Alexander Graham Bell Association for the Deaf and Hard of Hearing 3417 Volta Place, NW, Washington, DC 20007 202.337.5220; 202.337.5221 (TTY) WWW.AGBELL.ORG American Society for the Deaf Children P.O. Box 3355, Gettysburg, PA 17325 717.334.7922 (TTY) WWW.DEAFCHILDREN.ORG American Speech-Language-Hearing Association 10801 Rockville Pike, Rockville MD 20852 301.897.5700 (TYY) WWW.ASHA.ORG Child Hearing Loss 14