Roles of Speed vs. Inhibition‐Concentration in Speech Recognition of Mandarin Cochlear Implant Users

ABSTRACT Objectives Neurocognitive factors contribute to heterogeneity in cochlear implant (CI) success. This study addresses three gaps: (1) whether long, low‐redundancy sentences in quiet vs. short, high‐redundancy sentences in noise recruit different cognitive involvement; (2) the methodological conflation of processing speed with inhibition‐concentration; (3) the scarcity of tone language evidence in understanding the cognitive‐speech relationship. Methods Twenty‐five postlingually deafened Mandarin CI users completed long‐sentence recognition in quiet (Mandarin Chinese Adaptation of AzBio Sentence, CMnBio) and short‐sentence recognition in four‐talker babble noise (the BKB Sentences in Noise, BKB‐SIN). Auditory input quality was assessed using the Spectral‐Temporally Modulated Ripple Test (SMRT). The Shape Trail Test, a pencil‐and‐line task, was used to assess processing speed (STT‐A/B), and inhibition‐concentration (STT‐B). Because STT‐B reflects both processing speed and inhibition‐concentration, the latter was isolated using STT‐B.A (the residual of STT‐B on STT‐A). Independent contributions to recognition were assessed with hierarchical regression analyses. Results SMRT, STT‐A, and STT‐B showed correlations with both sentence outcomes, whereas STT‐B.A correlated solely with BKB‐SIN. In regression models controlling for SMRT, STT‐A explained significant variance in CMnBio ( β = −0.507, p = 0.001) and BKB‐SIN ( β = −0.371, p = 0.012). STT‐B.A contributed only to BKB‐SIN ( β = −0.318, p = 0.014). Conclusion Information processing speed shows a general association with sentence recognition in both quiet and noise, whereas inhibition‐concentration shows a noise‐specific association in Mandarin CI users. This study highlights the importance of methodological distinction separating these two cognitive functions and extends cognition‐speech links to tonal languages. Level of Evidence 3