Hearing-and-Visual-Disabilities听觉与视觉障碍课件.ppt

1、Hearing and Visual ImpairmentslDr.Shawnee WakemanHearing and Visual ImpairmentslTypeslCharacteristicslPrevalencelCauseslPreventionlAcademic Instructional PracticeslTechnologyHow does hearing work?lSound waves pass through mediumlEardrum vibrateslVibrations sent to inner earlPass to receptor cellssen

2、d impulses to brainlBrain translates impulses to soundTypes of Hearing ImpairmentslDeaflHard-of-HearingHard-of-HearinglMeans significant hearing losslMinimal loss:Loss of greater than 15-25 dBCan miss up to 10%of classroom speechlMild to moderate loss:26 to 50-55 dBlSevere hearing loss:71 to 90 dBlP

3、rofound hearing loss:Greater than 91 dBDeaflProfound or severe hearing losslNot able to use hearing to understand speech(may perceive some sound)lSpeech range loss of greater than 60 dBAge of OnsetlCongenitally deafPresent at birthlPrelingually deafOccurs before language develops(95%occurrence)lPost

4、lingually deafOccurs after language is developing(typically after age 2)Types of Hearing LosslConductiveOften corrected through surgery or medical treatmentHearing aids beneficiallSensorineuralInner earUsually cannot be corrected Sound distorted,if any at allAmplification may or may not helpPrevalen

5、celHearing loss in children is the#1 birth defect in the USl1/1000 babies born profoundly deafl2-3/1000 babies born with less severe hearing lossl0.14%of children in school are classified as deaf or hard of hearingl44%of children deaf or hard of hearing are from diverse backgroundslHard to count tot

6、al#of children who are deaf/hard of hearing or have multiple disabilities because of varying criteria in different states and becauseThe US Department of Education reports children by their primary disability,which may not be hearing related5 Major Causes of Hearing LossBacterial infectionsMeningiti

7、s(leading cause of post-lingual hearing loss)Pre-or post-lingualPrenatal infections of motherMaternal rubellaCongenital syphilisCongenitalExcessive noisePre-or post-lingualHeredityleading cause of deafness(except during rubella epidemics)Pre-or post-lingualOtitis mediaPre-or post-lingualCauses of He

8、aring LossOther CauseslPrematuritylBlows to headlRh incompatibilitylSide effects of antibioticslViral infectionsmumps,measleslAnoxia(deprivation of oxygen)at birthlExact cause unknown for up to 50%of hearing lossPreventionlEarly detectionUniversal screening of newbornslMedical technologyCochlear imp

9、lantsMiddle ear implantslIncreased public awarenessEarly identification and intervention(e.g.,Ottis media)Good health care for childrenlLesson noiseTeaching Approaches for Children with Hearing DisabilitieslBilingual-Bicultural ApproachlTotal communication approachUses American Sign Language(ASL)(ma

10、nual communication)and oral speechlCued speechUses hand signals to accompany oral speechlOral only approachStudents use as much residual hearing as possibleStudents lip-read and speakNo signingBilingual-Bicultural ApproachAmerican Sign LanguageControversy:lOral approach vs.Manual approachAlexander G

11、raham BellEdward GallaudetInstructional PracticeslKeep background noise to a minimumlSeat students where they can see everyone speakinglUse visual displayslDefine key vocabulary words slowly and carefullylUse manipulatives to explain math conceptslShow multimedia presentations with subtitleslHave st

12、udents share their noteslUse maps,globes,charts to demonstrate conceptslProvide students with opportunities for discussionlFace deaf/hard-of-hearing students when speakingTechnologylAssistive listening devicesHearing aidsFM transmission devicesAudio loopslTelecommunication devicesText telephone(TTY)

13、Closed captionsOpen captionslComputerized text-to-speech translationslAlerting devicesWhat does ADA mean for the deaf?lAny building with 4 or more pay phones must have a TTYlEach type of public accommodation must have a TTYlMeeting rooms for more than 50 people must have permanent assistive listenin

14、g systemslHotel/motel rooms must have accommodations for the deaf.4%of first 100 rooms2%of additional roomsVisual ImpairmentsHow Vision WorksFour elements required for normal visionlLightlSomething that reflects lightlEye processing reflected image into electric impulseslBrain receiving and giving m

15、eaning to these impulsesTypes of visionlVisual efficiencyHow well a person uses sightlVisual acuityHow well a person can see at various distanceslPeripheral visionOuter area of the visual fieldlTunnel visionSevere limitation in peripheral visionlCentral vision/field of visionWhen gazing straight ahe

16、ad,normal eye is able to see objects within a range greater than 20 degrees and up to 180 degreesTypes of visual disabilitieslLow visionIndividuals can use sight to learnVision interferes with daily functioninglBlindnessIndividuals use touch and hearing to learn no functional use of sightEducational

17、 Settingsl52%spend time in regular classesl70%-regular classes with some time in resource class for“Visually impaired”l8%attend private residential centersSigns of Visual Disabilitiesl5%of preschoolers have eye problems which could lead to vision loss if untreated.lHalf of the 2-3 million people wit

18、h glaucoma dont know they have it.l1 in 7 people age 40 and over have cataracts.lPeople with diabetes are 25-30 times more likely to lose sight than the general public.Listening SkillslSound awarenesslAuditory attendinglAuditory attention spanlSound localizationlAuditory discriminationlAuditory memo

19、ryPrevalencel1.3 million Americans are legally blindl10 million with low vision or blindnessMajority of these people over age 65lWorldwide,4%of ALL blind people are childrenlLess than 0.04%of schoolchildren have visual disabilities and receive special servicesOf this group,1/3 are legally blindlHalf

20、 of young children with visual disabilities have more than one disability and are often included in the multiple disabilities categoryBraillelIn 1963,50%of persons with severe visual disabilities used Braille;in 1992,only 10%of blind students use BraillelIDEA says IEP Team MUST address the use of Br

21、aille for children with visual impairmentsCore CurriculumlPart IParallels curriculum of sighted peers,with pre-learning and adaptation necessary for successlPart IICompensatory skills(i.e.,communication modes)Orientation and mobilitySocial interaction skillsIndependent living skillsRecreation and le

22、isure skillsCareer educationUse of assistive technologyVisual efficiency skillsVisual Disability AssociationslVisual and Hearing ImpairmentUshers SyndromelAssociated with LDTurner SyndromelAssociated with AutismAspergers SyndromeSavant SyndromeAutistic SpectrumAutistic behaviors are common in childr

23、en with Fragile X syndromeEducational ApproacheslMust provide TACTILE experiences to aid students with visual impairmentslStudents need concrete examples:ManipulativesAbacusClassroom AccommodationslTeachers must provide consistent organization,expectations,and consequenceslChange teaching style to i

24、nclude:Advance organizersOral summariesEnlarged printHandouts of lecturesExtend time on assignments and testsAudio tape lecturesUse terms that concretely name their referentslAllow students to reposition themselves for different activities to enhance opportunities to see and learnlRemove obstacles a

25、nd hazardsHalf open doors can be dangerousTechnologylOptaconOptical-to-tactileConverts print to readable,vibrating formraised pinslKurzweil Personal ReaderOptical character recognition systemScans and reads printed text up to 350 wpmCosts$1500-$4000lComputersMagnify screen images Speech recognition softwardlBrailleHigher employment rates for those who use itRequires extensive trainingCumbersome and slow12wpmTeachers cant read BrailleNational decline of people who use Braille l1960-50%,l2000-10%