Cochlear implant electrode place and pulse rate discrimination improve with training without cross cue transfer

Cochlear implant (CI) users typically have poor pitch resolution compared to normal-hearing individuals. This study investigated whether training on electrode place or pulse-rate cues could improve pitch discrimination in CI users (n = 12; four females, eight males) and whether such training generalized across place, rate, and congruently combined place–rate cues. Half of the participants began with place-pitch training and the other half with rate-pitch training for 2 weeks, then switched to training on the alternate cue for 2 weeks. Discrimination thresholds were measured using a two-interval, forced-choice, pitch-ranking task at baseline, weekly, and post-training for place, rate, and combined cues. Testing was performed at 110, 220, 440, and 880 Hz using a standardized research frequency allocation on each participant's active cochlear nucleus electrode array. These frequencies were typically assigned to electrodes 20, 17, 14, and 11. Post-training performance significantly improved on the specific cue trained during each block, with no evidence of cross-cue generalization. Similarly, training on either cue did not significantly improve combined place–rate discrimination thresholds within individual training blocks, though performance improved across the entire training period. Thus, longitudinal training improved CI users' pitch-ranking abilities, but effects were largely cue specific, suggesting that targeted pitch training can enhance perceptual acuity with limited generalization across pitch cues.