Hearing Loss, Cochlear
Conditions
Keywords
Cochlear implant
Brief summary
The aim of this study is to investigate the effect of varying additional factors on loudness summation in Neuro Zti Cochlear Implant users.
Detailed description
Primary objective: \- To assess the effect of the number and spatial distribution of active electrodes on the stimulation charge required to achieve the loudness associated with C and T levels (Experiment 2). Secondary objectives: * To assess how loudness is affected by changes in electrical charge of individual pulses made by adjusting the pulse amplitude versus adjusting pulse duration (Experiment 1). * To assess how loudness elicited by a train of pulses is affected by the duration of that pulse train (Experiment 3). Experiment 1: The test will investigate the effect of loudness on changes in electrical charge of individual pulses, made by separately adjusting pulse amplitude or pulse width. The electrical charge required to elicit different loudness (just-audible, soft, medium, comfortable, loud but comfortable) either when increasing the amplitude or the duration of the pulses. Experiment 2: The test will investigate the effect of the number of stimulating electrodes and their distribution within the cochlea on the stimulation levels required to achieve T-levels and C-levels and to elicit different loudness (just-audible, soft, medium, comfortable, loud but comfortable). Experiment 3: The test will investigate the effect on loudness of trains of pulses elicited by modifications to the duration of those trains, when operating around T and C levels. Stimulation durations ranging from 10 to 600 ms will be tested. Pulse trains will be presented to either one or several electrodes to elicit different loudness (just-audible, soft, medium, comfortable, loud but comfortable).
Interventions
DEVICEExperiment 1
Stimulation of one electrode at a time
DEVICEExperiment 2:
Stimulation in groups of 4, 8 and 12 electrodes
DEVICEExperiment 3
Stimulation total duration from 10 to 600 ms
Sponsors
Oticon Medical
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
OTHER
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Neuro One or Neuro 2 user * Unilateral or bilateral recipient * 12 months CI experience to allow for acclimatization to the CI sound processing and pathological changes that could alter the electrode - tissue interface and therefore T- & C-levels. * Having at least 7 step sizes on three electrodes in their current clinical map (for experimentation 1). * Able and willing to provide reliable threshold and comfort level judgements
Exclusion criteria
* Medical conditions that contraindicate the study tests (e.g. tinnitus, dizziness) * Unrealistic expectations from the candidate regarding the possible benefits, risks, and limitations that are inherent to the device * Unwillingness or inability of the candidate to comply with all investigational requirements * Vulnerable population
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Experiment 2: the effect of number of electrodes on loudness | 2 hours | Changes in electrical charge (nC) needed to achieve C-level and T-level. The charge is the results of Intensity\*Duration of a pulse, in µA and µs respectivelly. If either the amplitude or the duration of the pulse is modified, the charge will be modified as well. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Experiment 1 : the effect of pulse amplitude and pulse duration on loudness | 2 hours | Change of the charge (nC) required to elicit different loudness. The charge is the results of Intensity\*Duration of a pulse, in µA and µs respectivelly. If either the amplitude or the duration of the pulse is modified, the charge will be modified as well. |
| Experiment 3 : the effect of stimulation duration on loudness | 2 hours | Change of the charge (nC) to elicit th most comfortable loudness (C-level). The charge is the results of Intensity\*Duration of a pulse, in µA and µs respectivelly. If either the amplitude or the duration of the pulse is modified, the charge will be modified as well. |
Countries
France
Outcome results
None listed