ABSTRACT 2. METHODS Subjects 1. INTRODUCTION Evaluations

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1 OTOP.UBS # Speech Perceptin and Spken Language in Childrenwith-mpaired Hearing P Blarney, J Sarant J, T Serry J, R Wales J, C James J, J Barry J, G Clark J, M Wright 1, R Ther 1, C Psarrs 1, G Gdwin 1, M Rennie, & T Meskin 1 1 University f Melbume, Children's Cchlear mplant Centre, Sydney ABSTRACT Fifty seven children with impaired hearing aged 4-1 years were evaluated with speech perceptin and language measures as the first stage f a lngitudinal study. The Clinical Evaluatin f Language Fundamentals (CELF) and Peabdy Picture Vcabulary Test (PPVT) were used t evaluate the children's spken language. Regressin analyses indicated that scres n bth tests were significantly crrelated with chrnlgical age, but delayed relative t children with nrmal hearing. Perfrmance increased at 45 f the rate expected fr children with nrmal hearing fr the CELF, and 6 fr the PPVT. Perceptin scres were nt significantly crrelated with chrnlgical age, but were highly crrelated with results n the PPVT and CELF. The data suggest a cmplex relatinship whereby hearing impairment reduces speech perceptin, which slws language develpment, which has a further adverse effect n speech perceptin. 1. NTRODUCTON Over the last 5 years, technlgical advances in hearing aids and cchlear implants have made it pssible fr children with severe (7 t 9 db HL) and prfund (ver 9 db HL) hearing lsses t6 hear speech sunds at cnversatinal levels. This' des nt guarantee that they will develp nrmal spken language, and a wide range f speech perceptin and language abilities are typically fund fr this ppulatin. The factrs affecting perfrmance and the relatinship between hearing abilities and language develpment are under investigatin in a lngitudinal study being cnducted in Melburne and Sydney n a grup f primary-schl-aged children. The general hyptheses t be addressed in the study are that: There is a critical age (estimated t be arund 6 years) beynd which gd pen-set speech perceptin cannt be established. There is a critical level f hearing belw which gd pen-set speech perceptin cannt be established. Hearing such that n aided threshlds fall within the nrmal speech amplitude range fr frequencies f 15 Hz r abve is hypthesized t be belw the critical level. Hearing with a cchlear implant is hypthesized t exceed the critical level. Children using cchlear implants are especially interesting as there are reasnably large numbers wh have been deaf since birth, whse auditry capacity is suddenly and dramatically imprved. Study f this ppulatin is likely t result in new insight int the adaptability and/r limitatins f the develping human brain, as well as direct benefits t hearing-impaired children thrugh imprved habilitatin methds.. METHODS Data cllectin fr the lngitudinal study referred t abve cmmenced in The study will eventually include abut 1 children f primary-schl age, and will invlve five annual evaluatins f speech perceptin, language and speech prductin fr each child. This paper reprts and analyses all data cllected prir t May Subjects Fifty seven children with severely r prfundly impaired hearing had participated in the study prir t May The children were aged frm 4y m t 1y and were all enrlled in ral/aural prgrams in preschls r primary schls. Twenty fur children used the -electrde cchlear implant prduced by Cchlear Limited [] and thirty three were fitted with Cchlear implant users Hearing aid users Number f children 4 33 N. with cngenital lss 33 Mean age at device fitting 3.6 (1.7) vears unknwn Mean age at evaluatin 7.7 (1.9) years 8.4 (.) years Hearing lss pre-p. > 1 db HL 81(1'7) db HL Table 1: Children's details. Values in brackets are standard deviatins. hearing aids. Tw f the implant users became deaf at ages ne and three years, and all ther children had impaired hearing frm birth... Evaluatins Speech perceptin was evaluated with a mnsyllabic wrd test (CNC wrds []) and a sentence test (BKB sentences [3]) presented with auditin alne (A cnditin) and with auditin plus visin (AV cnditin). The tests were presented with live vice at a cmfrtable listening level at a distance f abut metre frm the child. The child's respnses were videtaped and scred ff-line independently by tw scrers. n a few cases, lder children gave written respnses. CNC wrds were

2 scred by whle wrds crrect. BKB sentences were scred by key wrds crrect, using a strict criterin which required the cmplete wrd t be prduced crrectly including mrphlgical markers fr plurality, tense, etc. 1 CNC wrds and 3 sentences cntaining 1 key wrds were presented in each cnditin fr mst children. Half this amunt was presented t 17 children whse evaluatin needed t be cmpleted within a single day. The Clinical Evaluatin f Language Fundamentals (CELF-3 and CELF-Preschl [4]) and the Peabdy Picture Vcabulary Test (PPVT-R and PPVT- [5]) were used t evaluate the children's spken language. Bth tests have been nnned with large grups f nnnally-hearing children and each scre may be expressed as an equivalent age, ie the age at which an average nnnally-hearing child wuld attain the given scre N 6 4 m,m ~,,, DAuditry Auditry-Visual ~ r Percentile range f scres Figure : Number f children gruped by CNC wrd scres Dlmplant D Hearing Aid Figure shws the distributins f scres n the CNC Wrd Test in the A and AV cnditins fr implant and hearing aid users cmbined. Scres were spread ver extremely wide ranges fr bth cnditins, and this applied t the BKB sentence test and CNC phneme scres in bth cnditins als. Althugh each perceptin test yielded a wide range f scres, there were n strng crrelatins with the chrnlgical ages f the children (Table ). As an example, Figure 3 shws the BKB Sentence scres in the A cnditin as a functin f age. CNCav CNCa Figure 1: Mean speech perceptin scres. 3. RESULTS 3.1. Speech Perceptin BKBav BKBa Figure shws the mean scres fr each perceptin test fr the A and AV cnditins with the children separated int implant and hearing aid users. There was n significant difference between the implant and hearing aid users in the mean speech perceptin scres fr either perceptin test in either cnditin (p>.5). Rel!:ressin line r D CNC AV = 3.5 x Age CNC A = 1. x Age BKB AV = 3.6 x Age BKB A =.7 x Age Table : Regressin analyses f perceptin scres in versus chrnlgical age in years D D Age in years Figure 3: BKB Sentence scres in the auditry cnditin. The equatin f the regressin line is given in Table. 3.. Spken Language Mean chrnlgical ages and equivalent ages fr the PPVT and CELF language measures are shwn in Figure 4 fr the children

3 divided int implant and hearing aid user grups. The CELF-3 is designed fr ages 6 and ver, and the CELF-Preschl fr ages up t 7 years. All children were evaluated with the mre apprpriate f the tw CELF tests accrding t their language abilities, and many were tested with bth. The bars labelled "CELF" use the mre apprpriate f the tw tests (ie, if a child's equivalent language age was measured t be within the range fr the CELF-Preschl, then this test scre was used. f the child's equivalent age was greater than 6 years, the CELF-3 scre was used.) There were statistically significant differences (p<.5) between the implant and hearing aid users fr all three sets f CELF scres. These prbably arse because the hearing aid users were lder n average and had prbably been fitted with hearing aids earlier than the implant users, giving them lnger t learn t use the auditry signals. The scres n the PPVT and CELF were very highly crrelated (r =.85, p<o.oo) r:[J~-m-p~la-n-:-t-:D:-:H-:-e-a-r:-in-g~A:-:i~dl yrs 4' 3 1 +'==u-"""t""'=.jl "...l.rjl...-.ll lr Age PPVT CELF3 CELFpre CELF Figure 4: Mean chrnlgical ages and equivalent ages fr language measures. 16 r;:====::::::; oo 14 l:j,.lmplant 1 HAid 1 yrs O+-,r--...,...-~,-...,...-~---,- rl Chrnlgical Age in years Figure 6: Equivalent age fr the PPVT vs chrnlgical age. 1 -r '=""""'" l:j,.lmplant 1 OHAid 8 yrs 6 4 The subtests f the CELF-3 and CELF-Preschl can be classified as "receptive" r "expressive" and a standard scre f 1 is assigned t average perfrmance f nrmally-hearing children at each age, with a standard deviatin f 15 units. Thus it is expected that 68 f children with nrmal hearing will btain scres between 85 and 115 (within ne standard deviatin f the mean). Figure 5 shws that nly 17 ut f 57 children in this study had receptive language scres greater than 85, and.nly had expressive language scres in this range. Mean standard scres fr receptive and expressive language are equal by cnstructin fr the nrmally-hearing ppulatin, but there was a significant difference in this study. The mean fr receptive was 75, and the mean fr expressive was 7 (p<.5), indicating that expressive language was delayed mre than receptive language in this grup. O r----r------, ,..J ' Chrnlgical Age in years Figure 7: Equivalent age fr the CELF vs chrnlgical age. Rel!ressin line r D CELF Age =.45 x Age PPVT Age =.6 x Age Table 3: Regressin analyses f PPVT and CELF equivalent ages in years versus chrnlgical age in years.

4 r-=::---:---==---:- Receptive Expressive 3 5 N Standard scre ranges Figure 5: Number f children gruped by standard scres fr the receptive and expressive subsets f the CELF t::. t::.1mplant OHAid PPVT Equivalent Age in years Figure 8: BKB audi-visual scres vs PPVT equivalent age. n cntrast t the perceptin scres, the equivalent ages fr CELF and PPVT were significantly crrelated with chrnlgical age. These regressin lines are shwn in Figures 6 and 7, tgether with lighter lines with slpe equal t which indicate the mean perfrmance fr children with nrmal hearing. Equatins fr the regressin lines are given in Table 3. The steeper slpe f Figure 6 cmpared t Figure 7 suggests that the children are mre advanced in their vcabulary knwledge as measured by the PPVT than they are in ther aspects f spken language as measured by the CELF. This cnclusin is cnsistent with the bservatin that the mean standard scre fr the Wrd Assciatins subtest f the CELF-3 was within the nrmal range, while mean scres fr mst ther subtests fell bel~ the nrmal range. Bthryd et al [6] reprted a regressin analysis with a similar slpe f.6 fr 188 children with hearing lsses between 9 and 14 db HL The Relatinship between perceptin & language As shwn in Table 4, there were strng crrelatins between all the perceptin scres and the equivalent ages derived frm the PPVT and CELF language measures. Fr example, Figure 8 shws the BKB sentence scres in the AV cnditin pltted against PPVT equivalent ages. Nte that a small number f cases with BKB scres clse t 1 and PPVT equivalent ages greater than 8 years were mitted frm the regressin because f the ceiling effect at 1 fr the perceptin test t::.lmplant OHAid PPVT Equivalent Age in years Figure 9: BKB auditin alne scres vs PPVT equivalent age. Rel!ressin line r D CNC AV = 9.7 x CELF Age CNC AV = 8.1 x PPVT Age CNC A = 5.9 x CELF Age CNC A = 4.5 x PPVT Age BKB AV = 13. x CELF Age BKB AV = 1.7 x PPVT Age BKB A = 1. x CELF Age BKB A = 8.8 x PPVT Age Table 4: Regressin analyses f perceptin scres in versus CELF and PPVT equivalent ages in years. Figure 9 shws the crrespnding BKB Sentence analysis fr the A cnditin. The verall scres tend t be lwer and there is mre variatin than in the AV cnditin. The regressin cefficient is still highly significant althugh it accunts fr a smaller prprtin f the variance. 4. CONCLUSONS Mst f the children in the study began using an implant r hearing aid befre the age f six, mst have aided threshlds

5 .. within the nrmal speech range fr frequencies abve 15 Hz, and mst demnstrate a gd level f pen-set speech perceptin in accrd with the hyptheses listed in the intrductin. Language skills seem t have a majr effect n the speech perceptin scres f these children. t is likely that pr speech perceptin slws the develpment f spken language skills, s that there is an interactive effect rather than a causal relatinship between these tw variables. n the future, if individuals fllw the trends displayed by the grup, it is likely that their language skills wjj imprve (at abut half the nrmal rate) and their speech perceptin scres in the AV and A cnditins will increase as a cnsequence. Average BKB AV scres shuld apprach 1 fr PPVT equivalent ages f 8 years and ver (Fig 8), which crrespnds t a chrnlgical age f abut 13 years (Fig 6). n the auditin alne cnditin, perceptin scres are strngly dependent n language skills, but shw greater variability than in the AV cnditin, pssibly reflecting the different levels f residual hearing, auditry experience, and ther factrs within the grups f hearing aid and implant users. 5. ACKNOWLEDGMENTS The authrs wuld like t acknwledge the financial supprt f NH&MRC prject grant #9757 entitled "Binaural hearing and spken language develpment in cchlear implant and hearing aid users". The research wuld have been impssible withut the willing cperatin f the families f the children, St Mary's Schl fr Children with mpaired Hearing, Munt View Primary Schl, Princess Elizabeth Junir Schl, and the Sydney Children's Cchlear mplant Centre. 6. REFERENCES 1. Clark, G.M., Tng, YC., and Patrick, J.F. Cchlear Prstheses, Churchill Livingstn, Edinburgh, Petersn, G.E. and Lehiste,. "Revised CNC lists fr auditrytests",j. Sp. Hear. Dis. 17:6-7, Bench, J. and Dyle, J. The Bamfrd-Kwal-Bench / Australian Versin (BKB/A) Standard Sentence Lists, Lincln nstitute, Carltn Victria, Wiig, E.H., Secrd, W. and Semel, E. Clinical Evaluatin flanguage Fundamentals-Preschl, 199 and Clinical Evaluatin flanguage Fundamentals 3'd Editin, The Psychlgical Crp, Harcurt Brace, Dunn L.M. and Dunn L.M. Peabdy Picture Vcabulary Test, 3rd Editin, American Guidance Service, MN, Bthryd, A., Geers, A.E., and Mg, J.S. "Practical implicatins f cchlear implants in children", Ear & Hear. Vl 1, n 4, Supplement 81S-89S, 1991.

6 Minerva Access is the nstitutinal Repsitry f The University f Melburne Authr/s: Clark, Graeme M.; Wright, M.; Ther, T.; Psarrn, C.; Gdwin, G.; Rennie, M.; Meskin, T.; Blamey, P.; Sarant, J.; Serry, T.; Wales, R.; James, C.; Barry, J. Title: Speech perceptin and spken language in children with impaired hearing Date: 1998 Citatin: Blamey, P., Sarant, J., Serry, T., Wales, R., James, C., Barry, J., et al. (1998). Speech perceptin and spken language in children with impaired hearing. n CSLP '98 prceedings. 5th nternatinal Cnference n Spken Language Prcessing, Sydney. Persistent Link: File Descriptin: Speech perceptin and spken language in children with impaired hearing Terms and Cnditins: Terms and Cnditins: Cpyright in wrks depsited in Minerva Access is retained by the cpyright wner. The wrk may nt be altered withut permissin frm the cpyright wner. Readers may nly dwnlad, print and save electrnic cpies f whle wrks fr their wn persnal nn-cmmercial use. Any use that exceeds these limits requires permissin frm the cpyright wner. Attributin is essential when quting r paraphrasing frm these wrks.