MELUDIA - Online music training for cochlear implant users.

BACKGROUND: Music enjoyment is of importance for many cochlear implant (CI) users, and the interest in music training is high. But many CI users report that it is a challenge to find suitable training resources and that they stall because they don't know how to practice. Meludia is an online music training program that provides structured and guided music training for musically experienced and inexperienced children and adults. OBJECTIVE: The aim of the study was to evaluate the suitability of the Meludia music training software for CI recipients based on two research questions: (1) are the easiest exercises available easy enough for CI users, and (2) are there any gaps when progressing through levels and stars with increasing difficulty? METHODS: Thirty-eight adult MED-EL CI users completed fourteen exercises involving 5 different musical dimensions of the online music training program. RESULTS: Our results show that the easiest exercises available in Meludia are easy enough for CI users to be able to use this training resource independent of age, indication, duration of CI use or musical background. CONCLUSION: With Meludia we assessed and found a suitable and comprehensive training tool that allows CI recipients to work on individual goals regardless of their present abilities.

Interaural level differences and sound source localization for bilateral cochlear implant patients.

OBJECTIVES: The aims of this study were (i) to determine the magnitude of the interaural level differences (ILDs) that remain after cochlear implant (CI) signal processing and (ii) to relate the ILDs to the pattern of errors for sound source localization on the horizontal plane. DESIGN: The listeners were 16 bilateral CI patients fitted with MED-EL CIs and 34 normal-hearing listeners. The stimuli were wideband, high-pass, and low-pass noise signals. ILDs were calculated by passing signals, filtered by head-related transfer functions (HRTFs) to a Matlab simulation of MED-EL signal processing. RESULTS: For the wideband signal and high-pass signals, maximum ILDs of 15 to 17 dB in the input signal were reduced to 3 to 4 dB after CI signal processing. For the low-pass signal, ILDs were reduced to 1 to 2 dB. For wideband and high-pass signals, the largest ILDs for ±15 degree speaker locations were between 0.4 and 0.7 dB; for the ±30 degree speaker locations between 0.9 and 1.3 dB; for the 45 degree speaker locations between 2.4 and 2.9 dB; for the ±60 degree speaker locations, between 3.2 and 4.1 dB; and for the ±75 degree speaker locations between 2.7 and 3.4 dB. All of the CI patients in all the stimulus conditions showed poorer localization than the normal-hearing listeners. Localization accuracy for the CI patients was best for the wideband and high-pass signals and was poorest for the low-pass signal. CONCLUSIONS: Localization accuracy was related to the magnitude of the ILD cues available to the normal-hearing listeners and CI patients. The pattern of localization errors for the CI patients was related to the magnitude of the ILD differences among loudspeaker locations. The error patterns for the wideband and high-pass signals, suggest that, for the conditions of this experiment, patients, on an average, sorted signals on the horizontal plane into four sectors-on each side of the midline, one sector including 0, 15, and possibly 30 degree speaker locations, and a sector from 45 degree speaker locations to 75 degree speaker locations. The resolution within a sector was relatively poor.

ALA-induced fluorescence in the canine oral cavity.

OBJECTIVE: We examined whether 5-aminolevulinic acid (ALA) could enhance the spectroscopic contrast between normal and diseased oral tissues, without prolonged photosensitivity. BACKGROUND DATA: ALA is a promising photosensitizing agent. METHODS: Adose of 25 mg/kg of ALA was administered intravenously to five dogs with gingivitis and three dogs with oral cancer, respectively. Fluorescence was recorded from the diseased sites in the oral cavity in addition to normal sites. RESULTS: ALA-induced proto-porphyrin IX fluorescence at all gingivitis sites reached a peak in 2-3 h and returned to baseline in 24 h. Fluorescence from the gingivitis site was observed earlier and was higher than the fluorescence from the normal site. For dogs with cancer, fluorescence from the cancerous sites occurred earlier in time compared to gingivitis sites and was comparatively higher in intensity. CONCLUSION: The fluorescence from the diseased sites was found to be higher than the normal site. Clinical and fluorescence data suggest that a dose of 25 mg/kg may be satisfactory for diagnostic purposes and would have minimal side effects.