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Updated: Jun 6, 2026
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Dorsal Column Steerability with Dual Parallel Leads using Dedicated Power Sources: A Computational Model
Published on: February 10, 2011
Influence of widening electrode separation on current steering performance
Jorien Snel-Bongers1, Jeroen J Briaire, Filiep J Vanpoucke
1ENT-Department, Leiden University Medical Centre, Leiden, The Netherlands.
Ear and Hearing
|November 11, 2010
Summary
Spanning electrodes in cochlear implants is feasible but requires more current for loudness and reduces pitch discrimination. However, pitch perception remains linear, mimicking intermediate electrodes.
Area of Science:
- Auditory neuroscience
- Biomedical engineering
- Otolaryngology
Background:
- Current steering in cochlear implants enables more spectral channels than physical electrodes.
- Spanning, or current steering to nonadjacent electrodes, offers potential for bridging defective contacts or reducing electrode count.
Purpose of the Study:
- To investigate the effectiveness of electrode spanning in cochlear implants.
- To assess pitch perception, loudness effects, and linearity of current weighting coefficients during spanning.
Main Methods:
- Twelve postlingually deafened cochlear implant users participated.
- Psychophysical experiments assessed intermediate pitches (3AFC), loudness balancing (2AFC), and pitch matching (2AFC) at basal and apical cochlear locations.
- An adaptive staircase procedure was employed.
Main Results:
- Spanning required significantly more current compensation for equal loudness compared to adjacent electrode steering.
- A significant decrease in discriminable intermediate pitches was observed with spanning.
- Pitch progression remained linear, and pitch matching aligned with theoretical coefficients.
Conclusions:
- Electrode spanning over wider distances is feasible in cochlear implants.
- Increased spanning distance necessitates greater current compensation and slightly degrades pitch discrimination.
- Linear pitch progression is maintained, with equal current proportions to spanned electrodes mimicking intermediate electrode pitch.
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