Annals ofOloiogy. Rliinology & Uiryngnlcay 118(5):35()-355.© 2009 Annals l^iblishing Company. All rights reserved.

Self-Reported Listening Habits and Enjoyment of MusicAmong Adult Cochlear Implant Recipients

Lela Migirov, MD; Jona Kronenberg, MD; Yael Henkin, PhD

Objectives: We sought to assess the associations between self-reported listening habits and enjoyment of music, and thefollowing variables: age at implantation, gender, prelingual versus postlingua! deafness, duration of deafness, duration ofcochlear implant (CI) use. type of CI. speech coding strategy, and speech perception abilities.

Methods: A questionnaire on Hstetiing habits and enjoyment of music before the onset of deafness and after implantationwas sent to 85 adult CI recipients who had been using the devices for at least 6 months.

Results: Of the 53 responders. 39 (73.6%) listened to music after implantation. Listening to music was not significantlyrelated to age at implantation, gender, duration of deafness, duration of CI use. type of CI device, speech coding strategy,or open-set speech perception abilities. The 14 nonlisteners were postllngually deafened. The ratings of enjoyment werethe same for 22.6ÇÎ of patients, improved for 26.4'/i. and worse for 50.9'7r. Only 2 of 13 patients who played a musicalinstrument and 14 of 24 patients who sang before the onset of deafness resumed their musical activities.

Conclusions: Despite the decline in listening habits and in the enjoyment of music after cochlear implantation, mostpatients do listen to music. The changes in listening habits and enjoyment were not related to the selected backgroundvariables.

Key Words: cochlear implant, enjoyment, listening habits, music, self-report.

INTRODUCTION

Since the introduction of cochlear implants (CIs)in the early 1980s, cochlear implantation has be-come the tnost effective method for enhancing com-munication and speech perception abilities of hear-ing-impaired individuals with severe-to-profoundhearing loss.' An extensive body of literature indi-cates that most recipients of modem CI devices canunderstand speech using the device alone, at leastin favorable listening conditions. Nonetheless, sig-nificant challenges remain for speech perception inthe presence of noise and for the perception of mu-sic.'-^

Current CI devices provide inadequate auditoryinformation about complex musical sounds. First,they do not provide a sufficient input dynamic rangeto cover the wide range of levels in music.^ Second,they transmit broad features of the spectral envelopein terms of the place-frequency mapping of the mul-tiple-eleetrode array, and the stimulation rates areunrelated to the actual frequency components of theinput signals. Thus, the limitations of a CI devicewith regard to pitch resolution and the transmission

of fine timing features, together with the limitationsof an impaired auditory system, result in poor per-ception of music by CI recipients."* Although mostCI recipients can perceive rhythm similarly to nor-mal-hearing subjects, they experience significantdifficulty in the perception of timbre (totie quality),pitch, and tnelody. especially when rhythmic or ver-bal cues are not available.-^

Subjective appreciation of music docs not neces-sarily reflect the perceptual accuracy exhibited byCI recipients in "laboratory" situations.*-^ This isnot surprising, as in most cases "laboratory" stim-uli that include isolated physical features, such asmelody, rhythm, timbre, harmony, and loudness, areused to evaluate music perception. In real-life situ-ations, however, Cl recipients are more likely to beexposed to varied combinations of melodies, harmo-nies, rhythms, and timbres."" Moreover, the subjec-tive complexity of tnusie, which involves personal,situational, cultural, and emotional variables, is nottaken into account.

The few studies that looked into self-reported lis-tening habits and enjoyment of music suggest con-

From the Department of Otolaryngology-Head and Neck Surgery (Migirov, Kronenberg) and the Speech and Hearing Center (Henkin),Sheba Medical Center. Tel Hashomer. and the Department of Communication Disorders (Henkin). Sackler Faculty of Medicine, TelAviv University. Tel Aviv. Israel.Correspondence: LelaMigirov.MD.Dept of Otolaryngology-Head and Neck Surgery, Sheba Medical Center, Tel Hashomer. 52621,[srael.

350

et al. List ••ning Habits & Enjoyment ofMu.sic After Cochlear Implantation

siderable variability among CI reci])ients.^'^ Studiesfocused on enjoyment and satisfactjion indicate thatmusic sounds unpleasant, mechani

351

:ai, or too com-plex to recognize for some CI rec pients, whereasit is enjoyable for others.̂ •'̂ Two recent studies re-ported that music appreciation and ¡enjoyment werenot associated with the speech cocjing strategy"* ordifférent background variables (eg, residual hearing,duration of deafness, previous heaiing aid use. andside of CI).'" Thus, the factors that contribute to thewide variability are not yet known.

Based on the substantial variab Uty in listeninghabits and enjoyment of music of CI recipients andthe limited available data regardingfactors, the main objective of the p¡to assess the associations between ;tening habits and enjoyment of music and the fol-lowing factors: age at implantation

the contributingesent study was;elf-reported lis-

. gender, prelin-gual versus postlingual deafness, duration of deaf-ness, duration of CI use. type of CI, speech codingstrategy, and speech perception abilities. Our work-ing premise was that because several of these factorsexplain some of the variability in th: speech percep-tion abilities of Cl recipients, they ntiay also be relat-ed to listening habits and enjoyment of music. Sub-ordinate questions were whether previous musicalexperience was related to the resurnption of musi-cal activities, and whether musical style preferenceschange after implantation. Such data may contrib-ute to the unraveling of factors thai affect listeninghabits and enjoyment of music in piand may further assist clinicians inmal counseling to CI candidates.

MATERIALS AND METHODS

Tesi Measures. The questionnaire

tients with a CI,providing opti-

used in the pres-'̂ and adaptedeiU study was developed by Mirza e

to Hebrew. The questionnaire included items per-taining to music listening habits before the onsetof deafness and then with a CI. The answers weregraded on a scale of 0 to 10 to determine how oftenthe patients listened to music (0 = never, 10 = veryoften) and how much the patients enjoyed listeningto music (0 = not at all, 10 = very nuch) before theonset of deafness and with the CI. Additional itemswere related to singing and playing musical instru-ments before the onset of deafness and after implan-tation, the quality of musical sounds heard whileusing the device, and personal preferences for thetypes of music (ie, classical, pop/i'ock, jazz, folk,country, and religious music).

Statistical Analysis. Comparisons between listen-ers antl nonlisteners were performed by the Mann-Whitncy nonparametric test for continuous and ordi-

nal variables and the x~ tt-'st for categorical variables.The Wilcoxon test was used to assess the change inordinal variables after implantation. The McNemartest was used to evaluate the change in listeninghabits (eg. musical style preference) after itnplan-tation. A linear regression model was applied to thedata in order to examine the independent contribu-tion of each of the background variables to li.steninghabits and enjoyment of music alter implantation.Three model-building methods were used: forcedentry, forward selection, and backward elimination.

RESULTS

Fifty-three patients responded,yielding a responserate of 62.4%. The mean age of the 21 male and 32female responders was 44.9 ± 18.3 years. The meanduration of deafness was 22.05 years (range, 1 to 58years), and all patients had been using their CIs for atleast 6 months (mean duration of CI use. 5.07 years;range. 0.5 to 17 years). Thirty-five patients were us-ing Nucleus CI devices (7 with Nucleus 22 CI pro-grammed with SPEAK ISpcctral Peakj strategy, 19with Nucleus 24 CI with ACE | Advanced Combina-tion Encoder] strategy, and 9 with Nucleus FreedomCI with ACE strategy), and 18 patients were usingMed-El devices (8 with Combi 40+ CI programmedwith CIS+ ¡Continuous Interleaved Sampling] strat-egy and 10 with Pulsar Cl with CIS+ strategy). For-ty-four patients were postlingually deafened, andwith the exception of 2 patients, all exhibited open-set speech recognition (range, lO'/t to 90% on theAB [Arthur Boothroyd] monosyllabic word test").Nine patients were prelingually deafened, and withthe exception of 2 patients, all exhibited some levelsof open-set speech recognition (range of AB test re-sults, 5% to 40%).

Ofthe 53 CI recipients who responded. 39 (73.6%)listened to music after implantation and 14 (26.49Ê>)did not (see Table). These 14 patients were post-lingually deafened, whereas all prelingually deaf-ened patients reported listening to music (X" test,p = 0.04). Listening (versus not listening) was notsignificantly related to age at implantation, gender,duration of deafness, duration of CI use, type of CIdevice, speech coding strategy, or open-set speechperception abilities as measured by the monosyllab-ic AB test.

The responses of patients to the question of howoften they listened to music before the onset of deaf-ness and after implantation are shown in the Figure,A. The mean scores (±SD) decreased from 7.4 ± 3.0before the onset of deafness to 6.2 ± 3.3 after im-plantation, a difference that did not reach a level ofsignificance (p = 0.08).

"1'

352 Migirov et al. Listening Habits & Enjoyment of Music After Cochiear Impluntation

BACKGROUND INFORMATION AND ENJOYMENTRATING BEFORE AND AFTER COCHLEARIMPLANTATION OF LISTENERS VERSUS

NONLISTENERS

No. of patients (%)Age (y: mean ± SD)Duration of deafness

(y; mean ± SD)Duration of CI use

(y. mean ± SD)Male/female (No. of patients)Prelingual/postlingual deafness

(No. of patients)Enjoyment rating before onset

of deafness (mean ± SD)Enjoyment rating after implantation

(mean ± SD)Speech perception (AB scores

with CI: mean ± SD)

Listeners

39 (73.6)42.4 ± 18.722.8 ± 12.8

4.9 ±4.8

13/269/30

7.92 ±2.5

7.56 ±2.5

42 ± 25.3

Type of Cl and strategy (No. of patients)

Med-El Combi 40+ (CIS+)Med-EI Pulsar (CIS+)Nucleus 22 (SPEAK)Nucleus 24 (ACE)Nucleus Freedom (ACE)

496

128

Nonitsteners

14 (26.4)51.7 ± 16.419.9 ±17.8

5.3 ± 3.2

9/50/14

8 ± 3.2

1.93 ± 1.9

49.2 ±29.2

4117

1CI — cotrhlcar implant; AB — Arthur Boothroyd; CIS+ — Continu-ous Interleaved Sampling; SPEAK -vanced Combination Encoder.

- Spectral Peak; ACE - Ad-

Patients* ratings of how much they enjoyed lis-tening to music before the onset of deafness and af-ter implantation are displayed in the Figure, B. Theratings decreased significantly, from 7.9 ± 2.7 be-fore the onset of deafness to 6.1 ±3.4 after implan-tation (p = 0.01, paired Wilcoxon test). The ratingsof enjoyment of music before the onset of deafnessand then with a CI were the same for 12 responders(22.6%). worse with a CI for 27 (50.9%). and im-proved with a CI for 14 (26.4%). Of the 39 patientswith CIs who listened to music, 31 (79.5%) rated

10

their overall satisfaction with a score of 6 or greater,and 14 (35.9%) assigned this item the maximum sat-isfaction score of 10.

Effect of Background Variables. The number ofmusic listeners gradually decreased with increasingage: from 89.4% (17 of 19 patients) in the young agegroup (16 to 39 years), to 69.6% (16 of 23 patients)in the middle-aged group (40 to 59 years), to 54.5%(6 of 11 patients) in the older age group (60 years ormore). These differences, however, did not reach alevel of significance, even when the youngest andoldest groups were compared. Tweniy-six of the 35Nucleus users (74.3%) and 13 of the 18 Med-El us-ers (72.2%) reported that they listen to music withtheir CI. The Mann-Whitney test revealed that therewas no significant association between CI deviceand speech coding strategy and satisfaction wilh thesound provided by the CI. the postimplantation fre-quency of listening to music, or the postimplanta-tion level of enjoyment of music.

Of the 32 patients who were satisfied with thesound provided by the CI on a scale of 1 to 3 ( I =satisfied, 2 = ambivalent, and 3 = disappointed). 19were Nucleus users and 13 were Med-El users. The14 disappointed patients iticluded 11 Nucleus and 3Med-El users. The 7 patients who were ambivalentincluded 5 Nucleus and 2 Med-El users.

A linear regression model was applied to the datain order to examine the independent contributionof each of the selected background variables on theratings of patietits in temis of how often they lis-tened to music and how much they enjoyed it. Tbebackground variables were age at implantation, gen-der, duration of deafness, prelingual versus postlin-gual deafne.ss. duration of CI use. type of CI device,and speech perception abilities. The results indicat-ed nonsignificant associations between these back-ground variables and the patients' ratings.

0 141 12i 10^ 8

642O

D After (o = 53)

n

B10

Ratings of A) how often patients listened to music and B) how much patients enjoyed listening to music before onset of deafnessand after cochlear implantation. Ratings were provided on scale from 0 to 10 (0 = not at all; 10 = very often or much).

Migirov et al. Lisi ?ning Hahits & Enjoyment of Music After Coehlear Implantation 333

Resumption of Musical Activilies and Prior Musi-cal Experience. Oí ihc 39 CI palientK who li.stcned tomusic after implantation, II (28.2';musical activities immedialely aft

r ) resumed their;r initial .stimu-

lation. 13 (33.3%) after 1 to 3' moAths. 12 (30.8%)after 3 to 12 months, and the oth^r 3 patients af-ter more than I year. Twelve patiehts who enjoyedlistening to music before the onset of deafness didnot resume musical activities after implantation, be-cause they were disappointed with tjhe quality of the.sound. Two additional patients did not enjoy musiceither before the onset of deafnesstation.

Of the 13 responders who had

or after impian-

played a musi-cal instrument before the onset of deafness, only 2Med-HI Combi 40+ users, twin brolhers. continuedId play the organ, drums, and guitat Moreover, oneof them is a composer and the othe • is a singer in aprofessional group.

Fourteen of 24 responders (58.3|í!) who had en-joyed singing before the onset of döafness resumedsinging after implantation. (Six of them had contin-ued singing before implantation despite their hear-ing loss.) The others stopped sinking because ofhaving difficulties in discriminating .sounds or in

;nts returned toyears before re-

monitoring vocalization. Three patisinging after having stopped severalceiving aCl.

Musical Source ami Style Preferences. The dis-tribution of the preferred musical source was as fol-lows; 3 patients listened to music from all of theusual sources. 21 from radio. 14 from television. 4from computers. 16 from tapes, and 2 from MP3s.and 11 were able to enjoy live eoncörts. The report-ed change in the ability to enjoy music after implan-tation varied according to the preference of musicstyle among the 53 responders: there were 45.2%who had enjoyed classical music betlire hearing lossand 53.8%' after implantation. The pre-hearing lossand postimpiantation scores showed different trendsfor pop/rock, jazz. folk, country, amj religious mu-sic: 46% versus 35.9%. 24% versus 28r2%. 60%versus 30.8%'. 14% versus 7.7%, and 4% versus 0%,respectively. Classical and folk sounded the best for17 listeners (43.6%) each, pop/rock; and jazz for 9

2(5.1%).

had listened tomusic before their hearing loss widened their prefer-ences of musical styles after implantation. 16 of 37(43.2%) narrowed them.5 (13.5%)changed them toanother style, and 12 (32.4%) stayed with their orig-inal preferences. Notably, country rnusic devoteesenjoyed music more than the other;; before losingtheir hearing, and they returned to it and to music

(23.1%) eaeh, and country musie for

Four of 37 patients (10.8%) who

appreciation more quickly than the others.

Cochiear Implantation for Music Perception. Six-teen of the 53 responders (30.2%) stated that theywould have been interested in undergoing implanta-tion just for being able to listen to music. All but Iwere postlingualiy deafened, and 3 were musicians.This group of patients rated the enjoyment of musiesignificantly higher than the 37 patients who werenot motivated to undergo implantation for the pur-po.se of being able to listen to music (mean rating.8.4 versus 6.8; p = 0.036). Finally, the resumptionof listening to musie after implantation was rapid inthis group of 16 patients, varying between immedi-ately after initial activation to several months afler-ward.

DISCUSSION

The results of the present study indicated that de-spite the significant limitations of CI déviées in pro-viding adequate information required for the percep-tion of music, the majority of patients 047v) listenedto music after implantation. This rate is higher thanthe 65% reported by Brockmeier et al̂ and the 46%reported by Mir/a et al.'' From the growing body ofliterature regarding music perception in CI recipi-ents^ and the limited data regarding subjective self-reported listening habits and appreciation of music,it becomes elear that there is substantial variation inthe findings.

To date, the factors that contribute to the variabil-ity in listening habits and appreciation of music byCI recipients are controversial and not fully under-stood. Moreover, subjective appreciation of musiedoes not fully reflect the perceptual accuracy ex-hibited by CI recipients,-** since it involves person-al, situational. and emotional variables. Our studypatients had highly diverse musical backgrounds,ranging from composers and professional musiciansto individuals with very limited and even no interestin music. Listening (as opposed to not listening) tomusic after implantation was nol significantly relat-ed to age at implantation, gender, duration of deaf-ness, duration of CI use, type of CI device and cod-ing strategy, or speech perception abilities with theCI. A trend of decrease in the number of music listen-ers with increasing age was, however, still evident.In a previous study that utilized the same question-naire, listeners were more likely to be younger, hadhigher speech perception abilities, and had a shorterduration of deafness.^ These different results maystem from the inclusion of prelingually deafened CIrecipients in our cohort, whereas the study by Mir-za et al'' consisted of postlingually deafened recipi-ents only. Interestingly, all 9 prelingually deafened

354 Migirov et al. Listening Habits & Enjoyment of Music After Cochlear Implantation

patients of the present cohort were music listeners,whereas 32% of our postlingually deafened patientswere nonlisteners. Although postimplantation musicappreciation has been almost exclusively studied inpostlingually deafened recipients.^-^ an early studyby Eisenberg'- indicated that all 12 prelinguallydeafened CI recipients studied did listen to music. Itis reasonable to consider that not having prior musi-cal experience makes music more acceptable to pre-lingually deafened recipients. Postlingually deaf-ened patients, on the other hand, acquired the mentalrepresentations of musical sounds during their yearsof hearing and presumably use them for comparisonwith incoming stimuli provided by the impaired au-ditory system coupled to the CI device with its limi-tations. It is not surprising, therefore, that listeningto music may become devastating for postlinguallydeafened patients and lead the real aficionados ofmusic among them to become nonlisteners.

Despite the relatively high percentage of musiclisteners in the present study, the ratings of patientson how often they listened to music and how muchthey enjoyed it decreased after implantation. Thesefindings are in agreement with previous reports.^-^Fifty-one percent of our patients reported that theirenjoyment from music deteriorated, 26% reportedan improvement, and 23% reported that it was thesame. Notably. 36% of the listeners assigned themaximum enjoyment score of 10. A different trendwas evident in a study by Leal et al,'^ in whieh 86%(25 patients) reported deterioration in enjoyment,4% (I patient) reported an improvement, and 10%(3 patients) reported no change when compared tohow they enjoyed music before the onset of deaf-ness. Similarly, Tyler et al'-+ found that 83% of theircohort reported a decline in musical enjoyment.

This large variability in self-reported listeninghabits and enjoyment of music requires evaluationofthe contribution of potentially associated factors.Similar to previous reports, the present study indi-cates that listening habits (eg, how often patients lis-tened to music) and enjoyment of music are not sig-nificantly affected by age at implantation, gender,duration of deafness, duration of CI use, type of de-vice and speech coding strategy, or speech percep-tion abilities.^-'" Age was significantly correlatedwith enjoyment of music in previous studies, whichindicated a decline in enjoyment with increasingagg 6.8 Those authors suggested that changes in per-ceptual processing associated with aging may nega-tively affect the ability of the older CI recipient toenjoy complex stimuli such as *̂

For the CI recipients who were actively involvedin music (ie, playing, singing) before implantation.

the present findings are disappointing. Ofthe 13 pa-tients who had played a musical instrument beforethe onset of deafness, only 2 young, postlinguallydeafened twin brothers using Med-El Combi 40+devices continued to play the organ, drums, and gui-tar. Moreover, one of them is a composer and theother is a singer in a professional group. Of the 24recipients who enjoyed singing before the onset ofdeafness, only 14 resumed singing after implanta-tion. Taken together, all but 1 patient who playedmusical instruments and most (71%) ofthe singersreported that they were music listeners after implan-tation. Although musical experience and training be-fore implantation had been found to be weakly cor-related with accurate recognition of music,-*̂ our datasuggest that prior musical experience does affect,at least to some extent, the listening habits of mu-sic in patients with a CI device. In addition, where-as Gfeller et al*̂ noted that the same musical styleswere enjoyable for patients both before and after im-plantation, our results indicated that many Cl recipi-ents changed their preference of musical styles afterimplantation and some of them even widened therange of music to which they chose to listen.

In our experience, highly motivated CI users re-sumed musical activities soon after being fitted withthe device, and they trained themselves to use thenew device in musical settings, as well. Early ex-posure to music following cochlear implantationcan be especially beneficial to postlingually deaf-ened individuals, because they may successfully usetheir past musical experience and memory. The gapbetween ceasing and returning to musical activitiesis apparently not a major factor, because even thepatients who resumed listening to music more thanI year after implantation were able to enjoy musicvery much and participate in different musical ac-tivities. This finding is in line with the results ofGfeller et al.** who reported the positive infiuence oftraining on music appreciation after implantation.

Finally, it is interesting to note that 16 of our 53responders (30.2%). 3 of whom were musicians,stated that they would have been interested in un-dergoing implantation just for being able to listen tomusic. They rated their enjoyment from music sig-nificantly higher than did the patients who were notinterested in undergoing implantation for the sake ofmusic. Although differences in the background vari-ables (eg, duration of deafness, duration of implantuse) between these two groups were not evident, it ismost likely that patients who were willing to under-go implantation just for the sake of listening to mu-sic were more appreciative of music via a CI com-pared to via other sensory aids, such as hearing aids

el al. Lis ening Habits & Enjoyment of Music After Cochlear Implantation

and assistive listening devices, thithe onset of deafness.

CONCLUSIONS

Beyond the complex physical characteristics ofmusic, there are diverse subjective-al. situational, and cultural elemenself-reported music appreciation i.

355

t they used after

quality, emotion-:s, as well. Thus.part of a wider

picture of the perception of music among CI recipi-ents. Despite the decline in listening habits and en-joyment of music with a CI as compared to before

1. Friedland DR. Venick HS, Niparko.ciîchlcar iniplaiitation; the ctiecl of historyon predicted postofjerative performance.24:582-9.

2. Brown KD. Balkany TJ. Benefitsimplantation; a review. Curr Opin Otolaryrgoi2007:15:315-S.

?>. McDermott HJ. Music perception with cuchlear im-plants: a review. Trends Anipljf 2()04;8:49-82.

4. Gfeller K.Witt S,Adamek K.etal. [¡fleets of training ontimbre recognition and appraisal by postlirgually deafened co-chlear implant recipients. J Am AcadAudJdï 2002:13:132-45.

Glcllf r K. Olszewski C, Rychener M, et al. Recognitionof" ïcal-wurld" musical excerpts by cochle

the onset of deafness, the majority of CI recipientslisten to music. Listening habits and enjoytiient ofmusic were not associated with speech perceptionabilities or with any of the selected backgroundvariables, some of which are known to be related tospeech perception. This information should be pro-vided to CI candidates during counseling. Further-more, opportunities for music training at the earlystages of device fitting should be considered as ameans to enhance the willingness of CI users to lis-ten to music and derive enjoyment from it.

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