CSD 115 1st EditionLecture 25Outline of Last Lecture I. Basic function of the earII. The outer eara. Pinnab. Ear Canalc. Tympanic membraneIII. Middle eara. Ossiclesb. Eustachian tubec. Retracted ear drumd. Otitis mediae. Pressure equalization tubesIV. Inner Eara. Semicircular canalsb. CochleaV. Sequence of EventsOutline of Current Lecture I. Conductive Hearing Lossa. ProblemsII. Sensori-Neural Hearing Lossa. ProblemsIII. Mixed Hearing LossIV. Assessment of Hearing Lossa. Pure Tone Audiometryb. Acoustic Immittancec. Otoacoustic EmissionsV. Treatment Optionsa. Amplificationb. Cochlear Implantsc. Auditory Trainingd. Communication TrainingCurrent LectureHearing Loss: Normal hearing ranges from 10-15 dB Levels of hearing that exceed 15 dB are classified as hearing loss These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Conductive Hearing Loss- Caused by problems in the outer or middle ear - Anything that inhibits the transmission of sound from the environment to the inner ear- Results in a loss of intensity (loudness) of sound- Problemso ATRESIA OF THE EAR CANAL – Canal fails to develop at birth, or has been damaged by trauma; no treatment optiono BLOCKED EAR CANAL – Impacted Cerumen or foreign objects; removed by audiologist or physiciano EXTERNAL OTITIS – infection in the outer ear; treated with medicationo OTITIS MEDIA – infection and fluid in the inner ear; treated with medication and/or pressure equalization tubes o OTOSCLEROSIS – Spongy bone growth at the oval window and stapes; restricts transmission of sound; requires surgical removal of bone growthSensori-Neural Hearing Loss- Loss associated with a problem in the cochlea and/or acoustic nerve - Damage inhibits the structures in the inner ear from converting fluid movements into neural impulses or prevents them from being transferred to the auditory portion of the brain- Results in loss of intensity (loudness) AND distortion of frequencies (clarity) of sound- Problemso CONGENITAL – Born with poorly developed or misformed structures in the inner ear.o Much of congenital deafness is genetic – parents are deafo 9/10 children born deaf have parents who hear normallyo ACQUIRED – Damage to the inner ear occurs after birtho Bacterial infection such as untreated otitis media which leads to meningitis o Meningitis is inflammation of the brain coveringo Viral diseases such as chicken box, mumps, measleso PRESBYCUSIS – hearing loss associated with aging; usually begins in 60’s; progressive o NOISE INDUCED HEARING LOSS – chronic or repeated exposure to noise, such as that found in factories, produced by rock bands, experienced in the military, use of portable music players at loud levels…o ACOUSTIC NEUROMA – tumor on the acoustic nerveo OTOXICITY – damage to the inner ear as a side effect of drugso MENIERE’S DISEASE – sudden unilalteral hearing loss; additional symptoms include dizziness & vertigo, and tinnitus – ringing or roaring in the ears; recurring symptomsMixed Hearing Loss- Loss that result from problems in not only the outer/middle ear, but also the inner ear orauditory nerveAssessment of Hearing Loss- PURE TONE AUDIOMETRYo Using an audiometer to present single frequency tones to the patiento Allows audiologist to determine hearing thresholdo With children: Play audiometry (blocks/bucket) Visual reinforced audiometry (toys in response to response to attention)o Assesses the outer and middle ear- ACOUSTIC IMMITTANCEo Using a tympanometer (or immittance meter) to assesses function of middle earo Tests movement of the eardrum and acoustic reflexes in middle ear- OTOACOUSTIC EMISSIONSo Present clicks to the ear & measure the sounds produced by the shearing action of the hair cells as the sound is transmitted to the Organ of Corti o Assesses functioning of cochlea - Newborn Hearing Screeningso Use Otoacoustic emissions to diagnose deafnesso When hearing loss is identified by six months of age and treated, children are lesslikely to have delayed speech and language skills.- Auditory Brainstem Response (ABR)o Used when behavioral responses are unable to be obtained.o Measures brain wave or electrical potential that is generated when the ear is stimulated with sound; recorded through the use of surface electrodes.o Assesses function of auditory nerve and brainstem Treatment Options- Amplification o Hearing aidso FM systems Microphone & transmitter for speaker Receiver/amplifier for listener - Cochlear Implantso Early as 12 monthso Profound hearing loss, there will be a 6 month hearing aid trial before implanto Transforms sounds to neural signalo Electrodes stimulate the auditory nerve to send signal to the brain- Auditory Trainingo Begins after selection/fitting of hearing aid, FM system, or cochlear implanto Helps maximize ability to use residual hearing and listening deviceo May include: Speech (lip) reading - Focus on visible movements of lips, jaw, tongue Using body posture & facial expression to assist in perception of meaning - Communication Trainingo Oralists  Strongly promote teaching of oral speech to deaf children Goal is to help child function in hearing communityo Manualists  Believe that deaf child won’t be able to use oral language well enough to function well in hearing world Strongly promote teaching sign language  Goal is to help child be as successful as possible, by maximizing communication skills Desire is to fit into the non-hearing