Remote-Microphone Technology Fitting Procedures for Normal Hearing Children with Auditory DisordersArun Joshi, BS, Suzanne Wright, BA, Christine Anderson, BS, & Erin Schafer, PhD

The University of North Texas

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METHODS

CONCLUSIONS

American Academy of Audiology. (2008) Clinical Practice Guidelines for Remote Microphone Hearing Assistance Technologies for Children and Youth from Birth to 21 Years. Reston, VA: Strategic Documents Committee, Hearing Assistance Technology Task Force.

Schafer EC, Bryant D, Sanders K, et al. (2014a). Fitting and verification of frequency modulation (FM) systems on children with normal hearing. J Am Acad Audiol, In press

Schafer, E. C., Traber, J., Layden, P., Amin, A., et al. (2014b). Use of wireless technology for children with auditory processing disorders, attention-deficit hyperactivity disorder, and language disorders. Seminars in Hearing, 35(3), 193-205

REFERENCES

There are several populations of children who havenormal hearing but exhibit auditory listening difficulties inthe classroom. Moreover, there is strong subjective,behavioral, and objective research evidence to supportthe presence of auditory processing dysfunction innormal hearing children with auditory disorders, includingthose diagnosed with Autism Spectrum Disorder (ASD)(Schafer et al., 2014b). Recent publications support theuse of wireless, remote-microphone (RM) technology forimproving speech-recognition performance in noise andclassroom-listening abilities in children diagnosed withauditory processing disorder (APD), attention-deficithyperactivity disorder (ADHD), and ASD. As a result, anevidence-based remote-microphone (RM) technologyfitting procedure is warranted. An overview of twoprevious studies will be used to outline fitting proceduresfor normal hearing children with auditory disorders. Theprimary goal of the first study (Schafer et al., 2014a) wasto determine the validity of the AAA real-ear approach(2008) to fitting FM systems on children with normalhearing. The second study (Schafer et al., 2014b)replicated the fitting procedures from the first study onchildren who were diagnosed with the aforementioneddisorders.

ParticipantsStudy 1: 26 children, 5 to 12 years, with typical speech/language development and normal hearing thresholds of less than 25 dB HL from 250 to 6000 Hz.

Study 2: 12 children, 6 to 11 years, with normal hearing thresholds of less than 20 dB HL from 250 to 6000 Hz.

EquipmentParticipants in both studies were fit with bilateral PhonakiSense Micro FM receivers with Standard xReceivers andsmall domes. The receivers were synched to an inspirotransmitter. Real-ear measures were conducted using an Audioscan Verifit.

METHODSINTRODUCTION

Fitting Procedures1. Meet DSL targets at 1000, 2000, 3000, & 4000 Hz FM mic in the test box; real-ear mic in child’s ear; Verifit: select ‘FM’; ‘On-ear’; Speech-std[1]; FM volume adjusted, if necessary 2. Do not exceed estimated UCLSame settings, but MPO selected as the stimulus; Compared MPO to the estimated UCL3-4. Examine difference between REOR & REURTransmitter turned off; Verifit: ‘Open’ instrument; Speech-std[1] at 65 dB SPL.

Speech Recognition in NoiseIn both studies, fixed-intensity BKB-SIN sentences were presented at 0 degrees azimuth (60 dBA) with multitalker babble from 3 spatially-separated loudspeakers (65 dBA). Participants completed 4 conditions: (1) no FM system, (2) FM receiver on the right ear, (3) FM receiver on the left ear, and (4) bilateral FM receivers.

Loudness RatingsIn both studies, participants listened to BKB-SIN stimuli (+5 SNR) and were asked to rate the loudness of the same four conditions on a rating scale to confirm similar loudness ratings.

Study 2 Questionnaires & Listening ComprehensionBefore and after a RM technology trial period, parents and participants completed the Children’s Home Inventory for Listening Difficulty (C.H.I.L.D.). Some participants and teachers also completed the Listening Inventory for Education-Revised (L.I.F.E.-R) Children’s Auditory Performance Scale (C.H.A.P.S.). The children’s listening comprehension in noise was determined with an investigator-recorded version of the Listening Comprehension Test 2 in the presence of continuous four-classroom noise.

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The proposed fitting procedures met DSL targets, did not exceed UCLs, and produced minimal occlusion. The fitting resulted in “comfortable” or “comfortable but slightly loud” loudness ratings for all condition. All behavioral measures and questionnaires yielded significantly better results with the RM technology.

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No significant effect of output type

RESULTS

Figure 1. Fitting Goal #1: Meet DSL targetsIdentical results for Study 1 & 2

RESULTS

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Figure 2. Fitting Goal #2: Do not exceed UCLIdentical results for Study 1 & 2

MPO significantly lower than estimated UCL

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Figure 3. Fitting Goal #3: Avoid occlusion effectOnly done in Study 1

Significant difference of 3 dB, not clinically relevant

Figure 4. Speech recognition (Identical results for Study 1 & 2)

No significant differences; but we only do bilateral

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Significantly higher comprehension with FM

Figure 5. Listening Comprehension Only done in Study 2

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Figure 6. Parent C.H.I.L.D. RatingsOnly done in Study 2

Significantly higher ratings with FM

Funding for participant payment and equipment was provided by Phonak. We would also like to thank the participants in our study!

ACKNOWLEDGEMENTS