Abstract
The objective of this study was to compare the psychophysical performance of patients using the Nucleus Contour™ electrode array with that of patients using the straight banded-electrode array. In particular, we wished to consider how psychophysical parameters would differ for an electrode array positioned closer to the modiolus, and how this might influence both patient benefits and the design of speech processing strategies. Nine subjects participated in the study: four used the Nucleus straight array and five used the Nucleus Contour electrode array. Radiographic analyses found that the Contour array lay closer to the modiolus, was more deeply inserted and spanned a larger fractional length of the basilar membrane than the straight banded-electrode array. The results were analysed in terms of array type and of the position of the individual electrode band, both distance from the modiolus and longitudinal placement. Mean threshold was lower for the Contour array but maximum comfortable level was similar. Whereas threshold varied significantly with distance of electrode band from the modiolus, maximum comfortable level did not. Pitch varied fairly regularly with longitudinal position of the stimulated electrode, with the exception of one Contour subject. The forward masking profiles, using moderately loud maskers, were narrower for the Contour array, indicative of more localized neural excitation.
Original language | English |
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Pages (from-to) | 160-175 |
Number of pages | 16 |
Journal | Hearing Research |
Volume | 212 |
Issue number | 1-2 |
DOIs | |
Publication status | Published - Feb 2006 |
Externally published | Yes |
Keywords
- Cochlear implant
- Forward masking
- Loudness estimation
- Perimodiolar placement
- Pitch estimation
- Radial distance
- Spread of neural excitation