Improved speech perception in adult congenitally deafened cochlear implant recipients.

OBJECTIVE: To determine whether congenitally deafened adults achieve improved speech perception when auditory and visual speech information is available after cochlear implantation. STUDY DESIGN: Repeated-measures single subject analysis of speech perception in visual-alone, auditory-alone, and audiovisual conditions. SETTING: Neurotologic private practice and research institute. SUBJECTS: Eight subjects with profound congenital bilateral hearing loss who underwent cochlear implantation as adults (aged 18-55 years) between 1995 and 2002 and had at least 1 year of experience with the implant. MAIN OUTCOME MEASURES: Auditory, visual, and audiovisual speech perception. RESULTS: The median for speech perception scores were as follows: visual-alone, 25.9% (range, 12.7-58.1%); auditory-alone, 5.2% (range, 0-49.4%); and audiovisual, 50.7% (range, 16.5-90.8%). Seven of eight subjects did as well or better in the audiovisual condition than in either auditory-alone or visual-alone conditions alone. Three subjects had audiovisual scores greater than what would be expected from a simple additive effect of the information from the auditory-alone and visual-alone conditions alone, suggesting a superadditive effect of the combination of auditory-alone and visual-alone information. Three subjects had a simple additive effect of speech perception in the audiovisual condition. CONCLUSION: Some congenitally deafened subjects who undergo implantation as adults have significant gains in speech perception when auditory information from a cochlear implant and visual information by lipreading is available. This study shows that some congenitally deafened adults are able to integrate auditory information provided by the cochlear implant (despite the lack of auditory speech experience before implantation) with visual speech information.     

Cortical neural activity underlying speech perception in postlingual adult cochlear implant recipients

Auditory event-related potentials (AERPs) and the simultaneously obtained behavioral measures (performance accuracy and reaction time) were used to study speech perception in postlingual adult cochlear implant (CI) recipients and in normal-hearing (NH) controls. AERPs were recorded while subjects were performing oddball discrimination tasks with increasing acoustic-phonetic demand. The tasks consisted of pairs of natural syllables that differed by one of the following phonetic contrasts: vowel place, voicing, vowel height, and place of articulation. Results indicated that the P3 potential was comparable in CI recipients and NH controls when the acoustic cues to the perception of the phonetic contrast were accessible. With the reduction in accessibility to the essential temporal and/or spectral cues, CI recipients exhibited delayed (prolonged P3 latency) and less synchronous (reduced amplitude) central speech-sound processing compared to NH controls. Among the phonetic contrasts used in the present study the place of articulation contrast yielded (1) the most prominent differences between CI recipients and NH controls across all measures, and (2) significant correlations between the neurophysiologic manifestation of speech discrimination (i.e. P3 latency), and conscious integration of perceptual information (i.e. performance accuracy and reaction time). Thus, P3 exposed the difficulties imposed on the impaired auditory system of CI recipients especially when elicited by speech contrasts that required processing of brief temporal-spectral cues. These findings support the P3 potential as a sensitive neural index of cortical processing that may provide information regarding accessibility and neural encoding of distinct acoustic-phonetic cues in CI recipients.     

Audiovisual speech perception in elderly cochlear implant recipients

OBJECTIVES/HYPOTHESIS: This study examined the speech perception skills of a younger and older group of cochlear implant recipients to determine the benefit that auditory and visual information provides for speech understanding. STUDY DESIGN: Retrospective review. METHODS: Pre- and postimplantation speech perception scores from the Consonant-Nucleus-Consonant (CNC), the Hearing In Noise sentence Test (HINT), and the City University of New York (CUNY) tests were analyzed for 34 postlingually deafened adult cochlear implant recipients. Half were elderly (i.e., >65 y old) and other half were middle aged (i.e., 39-53 y old). The CNC and HINT tests were administered using auditory-only presentation; the CUNY test was administered using auditory-only, vision-only, and audiovisual presentation conditions RESULTS: No differences were observed between the two age groups on the CNC and HINT tests. For a subset of individuals tested with the CUNY sentences, we found that the preimplantation speechreading scores of the younger group correlated negatively with auditory-only postimplant performance. Additionally, older individuals demonstrated a greater reliance on the integration of auditory and visual information to understand sentences than did the younger group CONCLUSIONS: On average, the auditory-only speech perception performance of older cochlear implant recipients was similar to the performance of younger adults. However, variability in speech perception abilities was observed within and between both age groups. Differences in speechreading skills between the younger and older individuals suggest that visual speech information is processed in a different manner for elderly individuals than it is for younger adult cochlear implant recipients.     

Music appreciation and music listening in prelingual and postlingually deaf adult cochlear implant recipients

Abstract

Objective: To explore the music appreciation of prelingually deaf adults using cochlear implants (CIs). Design: Cohort study. Adult CI recipients were recruited based on hearing history and asked to complete the University of Canterbury Music Listening Questionnaire (UCMLQ) to assess each individual’s music listening and appreciation. Results were compared to previous responses to the UCMLQ from a large cohort of postlingually deaf CI recipients. Study sample: Fifteen prelingually deaf and 15 postlingually deaf adult cochlear implant recipients. Results: No significant differences were found between the prelingual and postlingual participants for amount of music listening or music listening enjoyment with their CI. Sound quality of common instruments was favourable for both groups, with no significant difference in the pleasantness/naturalness of instrument sounds between the groups. Prelingually deaf CI recipients rated themselves as significantly less able to follow a melody line and identify instrument styles compared to their postlingual peers. Conclusions: The results suggest that the pre- and postlingually deaf CI recipients demonstrate equivalent levels of music appreciation. This finding is of clinical importance, as CI clinicians should be actively encouraging all of their recipients to explore music listening as a part of their rehabilitation.     

Music perception in cochlear implant recipients: comparison of findings between HiRes90 and HiRes120

CONCLUSIONS: Increased spectral resolution via implementation of perceptual channels with HiRes120 (PSP) would seem to provide better perception of music than with standard HiRes, mainly from the point of view of music appreciation as recorded via the questionnaire. More specific tests are required for appreciation of timbre, preferably by application of protocols based on perceptual attributes using rating scales, which would not be biased by knowledge of music. OBJECTIVE: The objective of this study was to verify the hypothesis whereby the implementation of perceptual channels in HiRes120 may lead to an improvement in the perception of music, owing to an increase in spectral resolution. SUBJECTS AND METHODS: Music perception was studied in 12 adult subjects, making a comparison between performance with HiRes90 and HiRes120 with perceptual channels. Quality of perception, loudness and rhythm were all assessed via a questionnaire. Further tests included timbre recognition trials and pitch ranking. RESULTS: Whereas there was a significant improvement in appreciation of music as seen by the questionnaire, timbre and pitch trials seemed to be biased by various subjective factors and require further study using different criteria.     

Music activities and responses of young cochlear implant recipients

Abstract

Objective. The development of auditory receptive skills and spoken language is often delayed in children who use cochlear implants, which may affect their appreciation of and responses to music. This in turn may be interpreted as disinterest in music. A questionnaire was developed to determine whether differences in exposure and responses to music exist between young cochlear implant recipients and their normally hearing peers. Design. The questionnaire was developed by a multidisciplinary team and distributed to parents of preschool children with normal hearing and to parents of preschool children who had been implanted at least one year prior. Study sample. The cochlear implant group comprised 23 children and was gender and age matched (within ±2 months) to a group of children with normal hearing. Results & Conclusions. Young cochlear implant recipients receive similar exposure to audiovisual music media, parental singing and musical instruments at home. However, the data suggest that they receive less exposure to children's music presented without visual stimuli. Parents also reported less sophisticated responses to music for this group. The findings of this study have important implications concerning the provision of age-appropriate music habilitation materials and activities for young cochlear implant recipients.

Sumario

Objetivo. El desarrollo de habilidades para la recepción auditiva y para el lenguaje hablado, se retrasa frecuentemente en niños que usan implantes cocleares, lo que puede afectar su apreciación y sus respuestas hacia la música. Esto a su vez, puede ser interpretado como desinterés en la música. Se desarrolló un cuestionario para determinar si existen diferencias en la exposición y en las respuestas a la música entre usuarios pequeños de implante coclear y sus pares normo-oyentes. Diseño. Se desarrolló el cuestionario por un equipo multidisciplinario y se distribuyó a padres de preescolares normo-oyentes y a padres de preescolares implantados por lo menos un año antes. Muestra de estudio. El grupo de implantados fue de 23 niños, pareados por género y edad (rango de ±2 meses) con un grupo de niños normo-oyentes. Resultados y Conclusiones. Los niños implantados recibieron una exposición similar a la de la música por medios audiovisuales, al canto de los padres y a instrumentos musicales en el hogar. No obstante, los datos sugieren que fueron menos expuestos a la música para niños, presentada sin estímulos visuales. Los padres también reportaron respuestas menos sofisticadas a la música en este grupo. Los hallazgos de este estudio tienen importantes implicaciones que se relacionan con la provisión de materiales y actividades para la habilitación musical, apropiados para la edad, dirigidos a niños pequeños con implante coclear.     

Device nonuse among adult cochlear implant recipients.

OBJECTIVE: To examine the causes and prevalence of previous and current device nonuse among adults who have received cochlear implants. STUDY DESIGN: Retrospective case review. SETTING: Adult tertiary referral center for cochlear implantation. METHODS: Two hundred fourteen consecutively implanted adult patients. The length of implant use ranged from 1 month to 14 years. MAIN OUTCOME MEASURE: A period of 4 consecutive weeks of nonuse of cochlear implant, including both obligatory and elective nonuse. RESULTS: Twenty-nine adults (13.6% of implantees) were identified as having at some stage not used their device for a period of more than 4 consecutive weeks. The main reason was device failure (n = 11). Ten adults are current nonusers (4.7% of implantees). Reasons include surgical complication necessitating explantation (n = 3), comorbid illness (n = 3), elective nonuse (n = 2), audiologic complication (n = 1), and device failure (n = 1). CONCLUSION: The overall prevalence of device nonuse was noted to increase slowly with time. The role of psychologic factors in contributing to the decision of an individual to elect to opt out of device use remains unproven.     

Effects of residual speech and auditory deprivation on speech perception of adult cochlear implant recipients

Objective

Possible predictive factors of cochlear implant (CI) outcomes have been extensively reported in literature for different user groups such as prelingual pediatric or postlingual adult users. However, there remains unexplained outcome variability among adult CI users; therefore, research concerning these patients continues and many different variables have been reported. This study aimed at evaluating the relationship between preoperative speech reception capacity, residual hearing, duration of deafness, age of implantation, and postoperative monosyllabic word recognition scores (WRSs) in postlingual CI users.

The role of intensity upon pitch perception in cochlear implant recipients

OBJECTIVES: Pitch plays a key role in the perception of speech and music, the recognition of a speaker's voice, and in analyzing complex auditory patterns. To date, little consideration has been given to the influence of stimulation level on pitch perception. The aim of this study was to investigate the impact of a sound's intensity on pitch perception in cochlear implant recipients using monopolar stimulation. STUDY DESIGN: Thirteen patients with an average implant use of 4.13 years took part in this study. All patients were implanted with MedEl Combi 40/40+ cochlear implants. METHODS: In the first part of the study, we performed a pitch ranking procedure to confirm that all patients were able to judge pitch changes. Using a visual scale, study participants were then asked to compare the pitch of an intensity-constant reference tone with the pitch of a test tone of varying intensity. RESULTS: Eleven (85%) patients were found to perceive a clear change in pitch with changing stimulus intensity. Statistical analysis showed a strong positive correlation in 10 patients (correlation coefficients between 0.99 and 0.71) and a strong negative correlation in 1 patient (r = -0.92). CONCLUSIONS: The results suggest that a distinct relationship exists between pitch perception and intensity of the stimulus. To date, speech coding strategies do not support these findings. Nevertheless, we believe that for the optimized most natural perception of sounds, especially music, the described particularities of pitch perception need to be respected, and further investigations on this topic are necessary.     

Music mixing preferences of cochlear implant recipients: A pilot study

Abstract

Objective: Music perception and appraisal are generally poor in cochlear implant recipients. Simple musical structures, lyrics that are easy to follow, and clear rhythm/beat have been reported among the top factors to enhance music enjoyment. The present study investigated the preference for modified relative instrument levels in music with normal-hearing and cochlear implant subjects. Design: In experiment 1, test subjects were given a mixing console and multi-track recordings to determine their most enjoyable audio mix. In experiment 2, a preference rating experiment based on the preferred relative level settings in experiment 1 was performed. Study sample: Experiment 1 was performed with four postlingually deafened cochlear implant subjects, experiment 2 with ten normal-hearing and ten cochlear implant subjects. Results: A significant difference in preference rating was found between normal-hearing and cochlear implant subjects. The latter preferred an audio mix with larger vocals-to-instruments ratio. In addition, given an audio mix with clear vocals and attenuated instruments, cochlear implant subjects preferred the bass/drum track to be louder than the other instrument tracks. Conclusions: The original audio mix in real-world music might not be suitable for cochlear implant recipients. Modifying the relative instrument level settings potentially improves music enjoyment.     

Open-set speech perception in adult cochlear implant users with ossified cochleae

Abstract

This study describes open-set speech recognition in cochlear implant subjects with ossified cochleae and compares it to a control group with open cochleae. Twenty-one postlingually deafened adults with a Med-El Combi 40/40+GB splitelectrode implant were matched to patients using a Med-El cochlear implant with a standard electrode. Speech recognition was assessed over an 18-month period. Splitelectrode patients improved significantly over time, but their scores were significantly lower and increased significantly slower than those of controls. Of 14 patients with a duration of deafness less than 20 years, average sentence test scores were 50%, and average monosyllabic word test scores were 31%. This study provides evidence that cochlear implantation is beneficial to patients with ossified cochleae, but early implantation is advisable.     

Speech perception and auditory performance in Finnish adult cochlear implant users

Abstract

Objective This study aimed at investigating the association between speech perception and categories of auditory performance (mCAP) in everyday life for adult cochlear implant users.

Design A prospective repeated measures design over a two-year follow-up period was used.

Methods The speech perception and auditory performance of 19 Finnish-speaking adults were assessed before implantation and 1, 3, 6, 12 and 24 months after switching on the implant. Spearman's rank order correlation coefficients (r_s) were calculated between mCAP and sentence, word, syllable, vowel and consonant recognition. Pearson's product moment correlation coefficients (r) were calculated among the speech perception results.

Results The correlation between mCAP and the speech perception results was high and statistically significant (r_s = 0.81?0.85, p 0.0001), as well as the correlation among the speech perception tests (r = 0.79?0.92, p 0.0001).

Conclusions The speech perception tests used may be considered as good describers of everyday performance of the subjects of this investigation.     

Open-set speech perception in adult cochlear implant users with ossified cochleae

This study describes open-set speech recognition in cochlear implant subjects with ossified cochleae and compares it to a control group with open cochleae. Twenty-one postlingually deafened adults with a Med-El Combi 40/40+GB split- electrode implant were matched to patients using a Med-El cochlear implant with a standard electrode. Speech recognition was assessed over an 18-month period. Split- electrode patients improved significantly over time, but their scores were significantly lower and increased significantly slower than those of controls. Of 14 patients with a duration of deafness less than 20 years, average sentence test scores were 50%, and average monosyllabic word test scores were 31%. This study provides evidence that cochlear implantation is beneficial to patients with ossified cochleae, but early implantation is advisable.