Perception of timbre in adult Cochlear implant users: Comparison of Iranian and Western musical instruments

OBJECTIVES

Cochlear implants (CI) have dramatically improved speech perception for patients with sensorineural hearing impairment. However, listening to music is a great challenge for them. This study examined the perception and appraisal of Iranian musical instruments comparing with similar Western instruments.

METHODS

Eleven adult CI users and 25 normal hearing (NH) individuals participated in this study. Musical stimuli of three commonly heard instrument pairs were prepared. Participants were asked to identify the instruments and rate their appraisal on a ten-point Likert scale (0 = dislike very much, 10 = like very much).

RESULTS

The instrument recognition rate was 40.6% among the CI users, and the mean appraisal score was 5.2 ± 2.7. NH listeners had none significant higher scores on both tasks with a recognition rate of 50.0% and the mean appraisal score of 6.9 ± 1.5. Iranian instruments were more recognized in both groups. Regarding their appraisal, the mean score for both types was almost equal in the NH group, while CI users more appraised Iranian instruments.

CONCLUSION

In addition to better recognition of Iranian instruments, they were particularly better appraised in the CI group. Iranian instruments provide suitable musical pieces for CI recipients that can be considered in rehabilitation programs.

Music Appreciation of Cochlear Implant Users versus Normal Hearing Individuals

Introduction

Cochlear implants (CI) provide speech perception for patients with sensorineural hearing impairment; nonetheless, listening to music is a daunting challenge for them. The present study aimed to compare Iranian CI users and normal hearing (NH) controls in terms of musical habits and appreciation and investigate the possible effect of background variables.

Materials and Methods

A total of 37 CI users who underwent surgery at least 18 months before the study and 59 NH listeners were enrolled in this study. The participants were assigned to two age groups: group A (patients ≥15 years old) and group B (patients <15 years old). They were asked to complete the questionnaires to assess their music engagement.

Results

In group A, the mean score of music importance was significantly higher in CI users (8.7±2.1), as compared to that in NH subjects (5.8±2.3) (P=0.005). Participation in professional musical training and singing with music was not significantly different between the groups. In group B, the mean score of desire for music was not significantly different between CI users (8.2±1.8) and NH subjects (7.7±2.0). They participated in professional musical training and had a reaction to music almost equally. Singing with music was significantly less common in the CI group (CI 16[61.5%], NH (40[85.1%]) (P=0.023). Selected background variables had no significant effect on the music tendency and habits of CI users.

Conclusions

Iranian CI users tended to have a high level of music appreciation in both adult and children groups. Moreover, CI users and NH controls did not significantly differ in the importance of music, devoted time, participation in musical activities, and musical habits.

Relationship between Electrically Evoked Compound Action Potential Thresholds and Auditory, Language, and Speech Progress after Cochlear Implant Surgery

INTRODUCTION

Electrically evoked compound action potential (ECAP) is an objective auditory response that can be used in the programing of cochlear implants. The aims of this study were to monitor ECAP thresholds and auditory, language and speech progress for 6 months after cochlear implant surgery and to evaluate any relationship between them.

MATERIALS AND METHODS

Ten children with a mean age of 4.2 (±0.6) years and bilateral congenital and profound sensorineural hearing loss underwent cochlear implant surgery and post-operation auditory and speech training. The auditory, language, and speech abilities (Newsha level) and ECAP thresholds (for apical, medial and basal region of cochlea) were evaluated 1, 3 and 6 months after surgery.

RESULTS

ECAP threshold showed no significant improvement in any of the evaluated areas in the 6 months after surgery (P>0.05); however, the Newsha level improved for all patients (P=0.00).

CONCLUSION

There was no relationship between ECAP thresholds and auditory, language, and speech abilities (Newsha level) in the first 6 months after surgery. ECAP thresholds may be a poor indicator of improvement in auditory, language, and speech abilities, and depend on many factors.

Amplitude changes of the electrically evoked compound action potential in children with cochlear implants: preliminary results

OBJECTIVE

Use of electrical instead of acoustical stimulation has made much objective electrophysiological evaluation possible. This is useful for management process of young children before and after the cochlear implant. These evaluations have been used for assessment of neuronal survival before cochlear implant and for monitoring of prosthesis function during and after the surgery. Electrically evoked compound action potential is one of these tests which makes a valid and reliable objective evaluation possible. The aim of this study was to evaluate the potential's amplitude changes three months after receiving the device in pediatric cochlear implant recipients.

METHODS

In this longitudinal study, changes of the potential's amplitude in four given electrodes in four sessions after receiving the device are evaluated by approximately one month intervals in children implanted in Amir Alam and Hazrat-e-Rasoul hospitals, Tehran in July to December 2007.

FINDINGS

The mean amplitude of the electrodes did not significantly change in different sessions, while there was significant difference between the first and the other electrodes' responses in every session (P<0.05).

CONCLUSION

Due to high reliability of the responses, the clinician can fit the speech processor for a long time. Better responses in apical electrodes may lead to develop an effective coding strategy.