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Objective: Hearing loss commonly causes difficulties in understanding speech in the presence of background noise. The benefits of hearing-aids in terms of speech intelligibility in challenging listening scenarios remain limited. The present study investigated if phoneme-in-noise discrimination training improves phoneme identification and sentence intelligibility in noise in hearing-aid users., Design: Two groups of participants received either a two-week training program or a control intervention. Three phoneme categories were trained: onset consonants (C1), vowels (V) and post-vowel consonants (C2) in C1-V-C2-/i/ logatomes from the Danish nonsense word corpus (DANOK). Phoneme identification test and hearing in noise test (HINT) were administered before and after the respective interventions and, for the training group only, after three months., Study Sample: Twenty 63-to-79 years old individuals with a mild-to-moderate sensorineural hearing loss and at least one year of experience using hearing-aids., Results: The training provided an improvement in phoneme identification scores for vowels and post-vowel consonants, which was retained over three months. No significant performance improvement in HINT was found., Conclusion: The study demonstrates that the training induced a robust refinement of auditory perception at a phoneme level but provides no evidence for the generalisation to an untrained sentence intelligibility task.

Background: Children with hearing impairments, especially those using hearing devices such as the cochlear implant (CI) or hearing aid (HA), are sometimes not encouraged to attend music classes, as they or their parents and teachers may be unsure whether the child can perform basic musical tasks., Purpose: The objective of the current study was to provide a baseline for the performance of children using CIs and HAs on standardized tests of rhythm and pitch perception as well as an instrument timbre identification task. An additional aim was to determine the effect of structured music training on these measures during the course of a school year., Research Design: The Intermediate Measures of Music Audiation (IMMA) Tonal and Rhythmic subtests were administered four times, with 6 wk between tests. All children in the study were also enrolled in "Music Club" teaching sessions. Measures were compared between groups and across the four testing sessions., Study Sample: Twenty children from a single school in Melbourne, Australia, were recruited. Eleven (four girls) had impaired hearing, including six with a unilateral CI or CI and HA together (two girls) and five with bilateral HAs (two girls). Nine were normally hearing, selected to match the age and gender of the hearing-impaired children. Ages ranged from 9-13 yr., Intervention: All children participated in a weekly Music Club--a 45 min session of musical activities based around vocal play and the integration of aural, visual, and kinesthetic modes of learning., Data Collection and Analysis: Audiological data were collected from clinical files. IMMA scores were converted to percentile ranks using published norms. Between-group differences were tested using repeated-measures analysis of variance, and between-session differences were tested using a linear mixed model. Linear regression was used to model the effect of hearing loss on the test scores., Results: In the first session, normally hearing children had a mean percentile rank of ∼50 in both the Tonal and Rhythmic subtests of the IMMA. Children using CIs showed trends toward lower scores in the Tonal, but not the Rhythmic, subtests. No significant improvements were found between sessions. In the timbre test, children generally made fewer errors within the set of percussive compared to nonpercussive instruments. The hearing loss level partially predicted performance in the Tonal, but not the Rhythmic, task, and predictions were more significant for nonpercussive compared to percussive instruments., Conclusions: The findings highlight the importance of temporal cues in the perception of music, and indicate that temporal cues may be used by children with CIs and HAs in the perception of not only rhythm, but also of some aspects of timbre. We were not able to link participation in the Music Club with increased scores on the Tonal, Rhythmic, and Timbre tests. However, anecdotal evidence from the children and their teachers suggested a wide range of benefits from participation in the Music Club that extended from increased engagement and interest in music classes into the children's social situations., (American Academy of Audiology.)

The study tests the hypothesis that vibrotactile stimulation can affect timbre perception. A multidimensional scaling experiment was conducted. Twenty listeners with normal hearing and nine cochlear implant users were asked to judge the dissimilarity of a set of synthetic sounds that varied in attack time and amplitude modulation depth. The listeners were simultaneously presented with vibrotactile stimuli, which varied also in attack time and amplitude modulation depth. The results showed that alterations to the temporal waveform of the tactile stimuli affected the listeners' dissimilarity judgments of the audio. A three-dimensional analysis revealed evidence of crossmodal processing where the audio and tactile equivalents combined accounted for their dissimilarity judgments. For the normal-hearing listeners, 86% of the first dimension was explained by audio impulsiveness and 14% by tactile impulsiveness; 75% of the second dimension was explained by the audio roughness or fast amplitude modulation, while its tactile counterpart explained 25%. Interestingly, the third dimension revealed a combination of 43% of audio impulsiveness and 57% of tactile amplitude modulation. For the CI listeners, the first dimension was mostly accounted for by the tactile roughness and the second by the audio impulsiveness. This experiment shows that the perception of timbre can be affected by tactile input and could lead to the developing of new audio-tactile devices for people with hearing impairment. [ABSTRACT FROM AUTHOR]

This study systematically investigated the effects of frequency, level, and spectral envelope on pitch matching in twelve bimodal cochlear implant (CI) users. The participants were asked to vary the frequency and level of a pure or complex tone (adjustable sounds) presented in the nonimplanted ear to match the pitch and loudness of different reference stimuli presented to the implanted ear. Three reference sounds were used: single electrode pulse trains, pure tones, and piano notes. The data showed a significant effect of the frequency and complexity of the reference sounds. No significant effect of the level of the reference sounds was found. The magnitude of effect of frequency was compressed in the implanted ear: on average a difference of seven semitones in the non-implanted ear induced the same pitch change as a difference of 19 to 24 semitones for a stimulus presented to the implanted ear. The spectral envelope of the adjustable sound presented to the non-implanted ear also had a significant effect. The matched frequencies were higher by an average of six semitones for the pure tone compared to a complex tone. Overall, the CI listeners might have matched the stimuli based on timbre characteristics such as brightness. [ABSTRACT FROM AUTHOR]

Musical enjoyment for cochlear implant (CI) recipients is often reported to be unsatisfactory. Our goal was to determine whether the musical experience of postlingually deafened adult CI recipients could be enriched by presenting the bass and treble clef parts of short polyphonic piano pieces separately to each ear (dichotic). Dichotic presentation should artificially enhance the lateralization cues of each part and help the listeners to better segregate them and thus provide greater clarity. We also hypothesized that perception of the intended emotion of the pieces and their overall enjoyment would be enhanced in the dichotic mode compared with the monophonic (both parts in the same ear) and the diotic mode (both parts in both ears). Twenty-eight piano pieces specifically composed to induce sad or happy emotions were selected. The tempo of the pieces, which ranged from lento to presto covaried with the intended emotion (from sad to happy). Thirty participants (11 normal-hearing listeners, 11 bimodal CI and hearing-aid users, and 8 bilaterally implanted CI users) participated in this study. Participants were asked to rate the perceived clarity, the intended emotion, and their preference of each piece in different listening modes. Results indicated that dichotic presentation produced small significant improvements in subjective ratings based on perceived clarity. We also found that preference and clarity ratings were significantly higher for pieces with fast tempi compared with slow tempi. However, no significant differences between diotic and dichotic presentation were found for the participants' preference ratings, or their judgments of intended emotion. [ABSTRACT FROM AUTHOR]

The cochlear implant is rightfully considered as one of the greatest success stories in Australian biomedical research and development. It provides sound sensation to hundreds of thousands of people around the world, many of whom are able to understand and produce speech. The device was developed in order to optimize speech perception, and parameters such as the choice of frequency bands and signal processing used were chosen in order to maximise perceptual differences between speech vowels. However, these settings are far from being suited for the perception of music, which might partly explain why many cochlear implant recipients cannot enjoy music through their implant. [ABSTRACT FROM AUTHOR]

Background: Studies using vocoders as acoustic simulators of cochlear implants have generally focused on simulation of speech understanding, gender recognition, or music appreciation. The aim of the present experiment was to study the auditory sensation perceived by cochlear implant (CI) recipients with steady electrical stimulation on the most-apical electrode. Methodology/Principal Findings: Five unilateral CI users with contralateral residual hearing were asked to vary the parameters of an acoustic signal played to the non-implanted ear, in order to match its sensation to that of the electric stimulus. They also provided a rating of similarity between each acoustic sound they selected and the electric stimulus. On average across subjects, the sound rated as most similar was a complex signal with a concentration of energy around 523 Hz. This sound was inharmonic in 3 out of 5 subjects with a moderate, progressive increase in the spacing between the frequency components. Conclusions/Significance: For these subjects, the sound sensation created by steady electric stimulation on the most-apical electrode was neither a white noise nor a pure tone, but a complex signal with a progressive increase in the spacing between the frequency components in 3 out of 5 subjects. Knowing whether the inharmonic nature of the sound was related to the fact that the non-implanted ear was impaired has to be explored in single-sided deafened patients with a contralateral CI. These results may be used in the future to better understand peripheral and central auditory processing in relation to cochlear implants. [ABSTRACT FROM AUTHOR]

Background: Enjoyment of music is an important part of life that may be degraded for people with hearing impairments, especially those using cochlear implants. The ability to follow separate lines of melody is an important factor in music appreciation. This ability relies on effective auditory streaming, which is much reduced in people with hearing impairment, contributing to difficulties in music appreciation. The aim of this study was to assess whether visual cues could reduce the subjective difficulty of segregating a melody from interleaved background notes in normally hearing listeners, those using hearing aids, and those using cochlear implants. Methodology/Principal Findings: Normally hearing listeners (N = 20), hearing aid users (N = 10), and cochlear implant users (N = 11) were asked to rate the difficulty of segregating a repeating four-note melody from random interleaved distracter notes. The pitch of the background notes was gradually increased or decreased throughout blocks, providing a range of difficulty from easy (with a large pitch separation between melody and distracter) to impossible (with the melody and distracter completely overlapping). Visual cues were provided on half the blocks, and difficulty ratings for blocks with and without visual cues were compared between groups. Visual cues reduced the subjective difficulty of extracting the melody from the distracter notes for normally hearing listeners and cochlear implant users, but not hearing aid users. Conclusion/Significance: Simple visual cues may improve the ability of cochlear implant users to segregate lines of music, thus potentially increasing their enjoyment of music. More research is needed to determine what type of acoustic cues to encode visually in order to optimise the benefits they may provide. [ABSTRACT FROM AUTHOR]