Assessment of Fine Structure Processing Strategies in Unilaterally Deafened Cochlear Implant Users

This study aimed to investigate the speech perception and subjective preference of unilaterally deafened cochlear implant users for two different speech coding strategies. Thirteen subjects who received a cochlear implant were provided with 2 maps that differed in the speech coding strategy, FS4 or FS4-p (MED-EL). Subjects were requested to alternate between the two maps daily for two weeks and to complete a questionnaire daily. Speech perception testing was performed using the adaptive Bamford-Kowal-Bench speech-in-noise test (BKB-SIN) after two weeks of alternating FS4/FS4-p use. The subjective benefit of FS4-p was significantly greater than the subjective benefit of FS4 on all five questions of the questionnaire. There was a significant improvement in speech perception scores over time under the S0/N0, S0/NHE, SCI/NHE test conditions. There was no significant difference between the speech perception scores obtained with FS4 and FS4-p coding strategies. For this group of cochlear implant recipients, assessment of the subjective preference for the speech coding strategy is likely to enhance motivation, compliance and consequently, outcomes.