A Comparison of Place-Pitch-Based Interaural Electrode Matching Methods for Bilateral Cochlear-Implant Users.
Kenneth K Jensen, Stefano Cosentino, Joshua G W Bernstein and 2 others
PMID 34057382WHAT IT FOUND
When matching electrodes between two cochlear implants, the ranking method is faster and more accurate than discrimination or matching.
Discrimination is slow and heavily biased by the testing range, making it unreliable for clinical mapping.
Key findings
01The ranking method was the only one immune to testing-range biases, whereas discrimination showed large biases and matching showed smaller but significant biases.
02Discrimination took nearly twice as long as ranking or matching and was the most susceptible to procedural errors.
03A single bias check is insufficient; valid pitch comparisons require checking testing-range effects, starting-point effects, and reference-electrode slopes.
STILL TO COME
How it was doneWhat they foundWhat it means for SLPs
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
The study included only six listeners, all with extensive practice in pitch tasks, which may not reflect naive patients. There is no ground-truth measurement for interaural pitch in CI users, so the 'correct' answer is unknown. The results are specific to bilateral CI users and may not generalize to bimodal or single-sided deafness patients. The ranking method assumes a monotonic place-pitch function, which can be violated in some patients.
Declared interests
The authors declared no potential conflicts of interest. The study was funded by the National Institute on Deafness and Other Communication Disorders (NIDCD) of the National Institutes of Health.
The easy way to misread this
Do not assume that a patient's inability to match electrodes perfectly indicates a cochlear implant problem or plasticity. The method used for matching significantly influences the result, with discrimination tasks showing large biases that are artifacts of the testing procedure rather than the patient's hearing.