Impact of migrating from paired to sequential stimulation on speech recognition in cochlear implant users

For many years, the paired stimulation strategy (P) was the standard configuration recommended by Advanced Bionics for cochlear implant users. However, recent evidence has demonstrated advantages of the sequential strategy (S), leading the company to adopt it as the new standard. Despite this change, many users continue to rely on the P strategy. In this context, the present study aimed to determine whether the S strategy truly provides advantages for users who have been using the P strategy for at least three months. Notably, no studies on this topic have been conducted in Portuguese or other Latin-based languages.

Nine cochlear implant users participated in the study, totalling eleven ears analyzed. All participants initially used maps programmed with the P strategy, with routine clinical follow-up. These maps were configured based on each user's measured comfort level (M). After reprogramming to the S strategy, the maximum stimulation levels (M) were readjusted according to individual comfort reports. Detection thresholds (T) were set at 10% of the M value for both the original and the updated maps. Each ear underwent a sentence recognition test using the P strategy and, subsequently, the S strategy, allowing for direct comparison of performance. For this comparison, the paired Student's t-test was used, the level of significance adopted was 5% (p < 0.05).

All participants demonstrated improved performance with the S strategy. The difference between strategies was statistically significant, with an average increase of 23% in sentence recognition following the transition to sequential stimulation.

The results indicate that the sequential strategy provides significantly better performance than the paired strategy.