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
Hearing Assistive Technologies for Deaf and Hard of Hearing Children Perry C. Hanavan, Au.D. Midwest Conference on Deaf Education Sioux Falls, SD July 11-12, 2011 HA Developments • Nanotechnology providing water resistant hearing aids HA Directional Microphones • Most HA have directional microphones • Proven beneficial technology • Data support use of directional hearing aids in some noisy school environments • Suggest use of directional mode should be limited to situations in which all talkers of interest are located in front of the student. (Ricketts & Galster 2007) HA Digital Feedback Reduction • Technology has dramatically improved the reduction of acoustic feedback • Helps increase HA gain without “whistle” HA Digital Noise Reduction • Significant increase in “ease of listening” with DNR (Bentler, Wu, Kettel & Hurtig 2008) • Spectral changes from noise suppression ALWAYS improve speech. – Therefore, we tentatively recommend DNR systems be routinely enabled for children of all ages…just like adults. (Dillon, Ching & Golding 2008) • DNR does NOT have negative effect on perception of nonsense syllables, words or sentences – Stelmachowicz et al 2010) HA Extended HF Frequency Bandwidth Stelmochowitz found bandwidth beyond 5 kHz (Stelmachowicz et al 2004) (Stelmachowicz 2010) Pittman found that children with HL require 3X the exposure to learn each new word and concepts due to reduced acoustic bandwidth caused by HL (Pittman 2008) • Most modern HA have bandwidth from 6 to 10 plus kHz • However telecoil use may only amplify to 4 kHz • Thus FM technology for speech and language develop may be better than telecoil-induction loop technology • However telecoil option remains critically import for: – Phone – More public facilities (churches, theaters, sports arenas, etc.) are getting looped (Get in the Loop initiative) AAA, HLAA, Sertoma 10,000 kHz Bandwidth Bandwidth & Phoneme ID in Students CAM2 • CAM2 software prescribes the amount of amplification of high-frequency sounds above 6000 Hz-required to restore audibility • Most HA software only prescribes amount of amplification to 6000 Hz • Higher frequencies help distinguish sounds such as “sh”, “ch” and “f” • Listening situations, such as in a room where several people are speaking at once—higher frequencies make it much easier to understand the person you want to listen/hear. • Higher frequencies can improve sound localization Loops &Telecoils-What Is It? Telecoil--Advantages • Universal • Convenient--no additional apparatus, special equipment , streamers, remotes, etc. • No battery drain • No pairing – universal signal worldwide/standardized • Most HA have T/TM/M options for classroom use • Inexpensive (little or no cost to parents) • No time delay from microphone to HA • Can accommodate hundreds of listeners in the loop • Most HA and all CI have telecoil • Used with all landline phones, many cell phones with T3/T4 ratings HA with Telecoils • • • • • • 7 of 28 CIC 8 of 10 ITC 20 of 42 RIC/RITE 24 of 35 “Slim- & Thin-Tube” HA 38 of 38 ITE 29 of 30 BTE (Oct 2010) (May/Jun 2009) (Jan 2010) (Feb 2010) (Sep 2010) (Jan 2009) Telecoil Available for CI Telecoil—Frequency Response • Currently, frequency response characteristics limited in low and high frequencies (decreased bandwidth) Telecoil—Orientation • Telecoil situated perpendicular to installed loop wire or telephone • Incorrect orientation of telecoil results in attenuated signal • Head orientation and tilting head may result in poor signal reception • Placement not ideal for landline phone Orientation & Frequency Response CI Telecoil Orientation • • • • MED-EL Opus 2: Advanced Bionics Harmony: Cochlear Nucleus 5: Cochlear Nucleus Freedom: Vertical 45 deg angle Horizontal Vertical Looping Options Beyond the Classroom • School – Auditorium – School secretary office – Librarian desk • Community – – – – – – Church Grocery store checkout Library checkout Transportation Ticket booths Drive-up windows Frequency Lowering HAs • Studies show that frequency lowering aids improve speech recognition with severe to profound high frequency SNHL – – – – – Simpson et al, 2005 Glista et al, 2009 Nyffeler 2008 Wolfe et al, 2010 Wolfe et al 2011 • “Non-linear frequency compression algorithm is the most important development in pediatric amplification in over a decade.” (Richard Seewald) Non-Linear Frequency Lowering High Frequency Loss • Phonak (Naida) and Widex (Inteo) hearing aids • Frequency lowering (frequency transposition) hearing aids for persons with un-aidable high frequency hearing loss. • Creates new acoustic cues for hearing /s/ sound important in plurals (e.g., books, it’s) • Speech recognition cues improve over time from initial fit • Students function better in classroom and in various communication situations (Glista et al 2009) High Frequency Lowering Compression • NLFC improves speech recognition and speech production for children with moderate to profound hearing loss • NLFC should be considered for all children moderate to profound high-frequency hearing loss • Verification is essential for success of these children • Kids with essentially no hearing above 1500 Hz should be referred for CI evaluation (Wolfe et al 2010) Hearing Tests for High Frequency • • • • University of Western Ontario Plurals Test Phonak Logatome Test BKB-SIN Recorded /sh/ and /s/, University Western Ontario UWO Plural Test • • • • Recorded test Open set test Female speaker 15 words familiar to school-aged children in both singular and plural form (/s/ or /z/ in final position) – – – – Skunk/skunks Book/books Fly/flies Crayon/crayons • Presented at 50 dB SPL from loudspeaker 1 meter directly in front of child UWO /s/--/sh/ Video Game Phonak Logatom Test • Adaptive, computer controlled test • Developed by Phonak • Female speaker: “My name is…” – – – – – – – ASA ASA (filter to 6 kHz) ADA AKA AFA ASHA ATA • Software track level in dB SPL that corresponds to 50% correct performance BKB-SIN BKB-SIN • 10 sentences presented twice • Increasing noise with each sentence • Indicates ability to understand speech in noise • Helps audiologist select appropriate hearing aid and hearing assistance technologies RITA, RIC & MARIC • RITA Receiver in the aid • RIC Receiver in canal • MARIC Mike and receiver in canal HA Streamers • Bluetooth streamers/Remote controls • System that allows HA to connect with virtually any audio device – cell phones, IPods, PDAs, TV, etc. • Short distance wireless communication • Can be worn around neck or held in hand • Battery drain increase • No standardization between various HA manufacturers Personal FM • FM/Radio Frequency Devices • The benefits of FM systems are well documented and include: – Eliminating negative effects of noise and reverberation on speech perception, and – maintaining constant speech input regardless of distance between the speaker and listener • (Boothroyd, 2004; Chisholm et al, 2007). – FM use specifically with cochlear implants, the overwhelming majority of these studies pertain to children in educational setting (Davies et al, 2001; Schafer & Thibodeau, 2006). – Research with children has shown significant improvement in speech understanding in noise when an FM system is used in conjunction with a cochlear implant (Davies et al, 2001; Schafer & Thibodeau, 2006). Personal Adaptive (Dynamic) FM • On the objective measures, Phonak adaptive FM processing resulted in significantly better speech recognition in noise compared to fixed FM processing for 68- and 73dBA noise levels. • On the subjective measures, all individuals preferred adaptive over fixed processing for half of the activities. • Adaptive processing was also preferred by most (8–9) individuals for the remaining 4 activities. (Thibodeau 2010) Phonak FM Recievers Binaural CI Advantages CIs and FM Systems • Remote Microphone • Bilateral Wireless Systems • Includes HA for non-CI ear if aidable with remote microphone • Meta-analysis: – Classroom amplification systems (3% improvement — not significant improvement) – Desktop amplification systems (17% improvement— significant improvement) – Personal FM systems—38% improvement—significant improvement over the other two) (Schafer & Wolfe 2010) Note FM component on CI MLxi Universal Receiver • Phonak’s universal Dynamic FM receiver. • When attached to the user’s hearing instrument, MLxi provides all the benefits of Phonak’s Dynamic FM technology. • Dynamic Speech Extractor - an algorithm that improves signal-to-noise ratios by up to 15 dB and speech scores in noise by dozens of percentage points. • Fully automated product; the user just needs to switch it on; child-proof and backwards compatible • Compatible with virtually all BTEs and cochlear implants • Compatible with all Phonak transmitters CI Performance in Noise w/o FM CI plus Personal FM • Personal FM system have been used to assist HA users for improving hearing in difficult listening environments • Personal FM systems are the most effective means to assist CI users to hear better in noise (Wolfe & Schafer, 2008; Wolfe et al, 2009) • Audiologists have been reluctant to consider personal FM because: – Multiple parameters that must be adjusted with some FM systems including: • Ratio of the FM input to the processor mic input (i.e., Mixing Ratio) • Gain of the FM receiver • Input Dynamic Range (IDR) CIs and FM Systems • Meta-analysis – HA or CI on 2nd ear (bilateral)—1.1 dB improvement on average – CI with FM on one side—13.3 dB improvement – 2nd CI or HA on second side— – Binaural FM—best signal option (Dynamic FM will improve listening in noise, social situations, restaurants, etc.) • Recommendation: – If family/school can afford, best option is binaural Dynamic FM with binaural CI or CI and HA – Next best option is Dynamic FM on 1st cochlear implant side (Wolfe 2010) Classroom Soundfield Amplification • Benefits – – – – – – – Children with temporary HL Improve S/N ratio Reduce teacher vocal fatigue Children with APD and ADHD (hearing in noise) Improves academic achievement and behavior Increased word and sentence recognition Improves literacy growth • Disadvantages – – – – – Do not use in place of Dynamic FM for HA and CI users Will not compensate for poor classroom acoustics Poor installation/systems may not be helpful Poor microphone management by teacher not helpful Unclear speech by teacher not helpful Classroom Amplification Systems Self install systems: • LightSpeed REDCAT • Phonak Dynamic SoundField Phonak Dynamic Soundfield • Inspiro Dynamic microphone • Compatible with Dynamic FM receivers, BAHA, other HA • Software updatable • Remote computer access • Monitors classroom environment and adjusts volume and frequency • Provides optima S/N ratio • Connects to Smartboard Questionnaire/Inventory/Survey • Adolescent SAC / SOAC Questionnaire • SSQ • Listening Inventories For Educators (L.I.F.E.) • Children’s Auditory Performance Scale (CHAPS) • SIFTER • CHILD • ELF Go to www.hear2learn.com for additional surveys Ling 6 Sound Check • Evaluate student at variety of distances to determine maximum distance Ling sounds heard • Ling 6 Sound Check Chart • Ling 6 Behavioral Daily Checklist • Ling 6 Recording Chart Functional Listening Evaluation • Determine how listening abilities are affected by noise, distance, and visual input in an individual’s natural listening environment • Designed to simulate listening ability in situations that represent actual listening conditions in student’s classroom– not sound booth • Administration of the evaluation, the student’s teachers, parents, and others gain understanding affects of adverse listening conditions encountered by the student. • The evaluation results are also useful in justifying accommodations, such as assistive listening devices, sign language or oral interpreters, notetakers, captioning, special seating, and room acoustic modifications. • Functional Listening Evaluation (Ying , 1990), (Ross, Bracken & Maxon, 1992) FLE (cont.) • Test administration takes approximately 30 minutes, including set up, with sentences and 20 minutes with words. 1. Auditory-Visual Close Quiet 2. Auditory Close Quiet 3. Auditory-Visual Close Noise 4. Auditory Close Noise 5. Auditory-Visual Distant Noise 6. Auditory Distant Noise 7. Auditory Distant Quiet 8. Auditory-Visual Distant Quiet Practical Hearing Aid Skill Tasks (PHAST) • Can student and parents pass the PHAST? • Perhaps modify this for use with assistive devices? (Desjardins & Doherty 2009) HA Functioning in Preschool Setting • Over half of the HA tested were determined to have at least one or more problems • Problems detected using listening and visual checks • Failure rates based on basic listening and visual checks among the HA examined in this study demonstrate no improvement over those reported in the 1970''s • The results re-emphasize the need for a national dialogue on this topic (Burkhalter et al 2011)