title: When Hearing Is Tricky: Speech Processing Strategies in Prelingually Deafened Children and Adolescents with Cochlear Implants Having Good and Poor Speech Performance.
abstract: Cochlear implants provide individuals who are deaf with access to speech. Although substantial advancements have been made by novel technologies, there still is high variability in language development during childhood, depending on adaptation and neural plasticity. These factors have often been investigated in the auditory domain, with the mismatch negativity as an index for sensory and phonological processing. Several studies have demonstrated that the MMN is an electrophysiological correlate for hearing improvement with cochlear implants. In this study, two groups of cochlear implant users, both with very good basic hearing abilities but with non-overlapping speech performance (very good or very poor speech performance), were matched according to device experience and age at implantation. We tested the perception of phonemes in the context of specific other phonemes from which they were very hard to discriminate (e.g., the vowels in /bu/ vs. /bo/). The most difficult pair was individually determined for each participant. Using behavioral measures, both cochlear implants groups performed worse than matched controls, and the good performers performed better than the poor performers. Cochlear implant groups and controls did not differ during time intervals typically used for the mismatch negativity, but earlier: source analyses revealed increased activity in the region of the right supramarginal gyrus (220-260 ms) in good performers. Poor performers showed increased activity in the left occipital cortex (220-290 ms), which may be an index for cross-modal perception. The time course and the neural generators differ from data from our earlier studies, in which the same phonemes were assessed in an easy-to-discriminate context. The results demonstrate that the groups used different language processing strategies, depending on the success of language development and the particular language context. Overall, our data emphasize the role of neural plasticity and use of adaptive strategies for successful language development with cochlear implants.
authors.affiliation: Institute for Biomagnetism and Biosignalanalysis, Muenster University Hospital, Muenster, Germany.|Jean-Uhrmacher-Institute for Clinical ENT-Research, University of Cologne, Cologne, Germany.
authors.forename: Magdalene
authors.initials: M
authors.lastname: Ortmann
authors.affiliation: Department of Psychology, University of Muenster, Muenster, Germany.
authors.forename: Pienie
authors.initials: P
authors.lastname: Zwitserlood
authors.affiliation: Department of Phoniatrics and Pedaudiology, Muenster University Hospital, Muenster, Germany.
authors.forename: Arne
authors.initials: A
authors.lastname: Knief
authors.affiliation: Institute for Biomagnetism and Biosignalanalysis, Muenster University Hospital, Muenster, Germany.
authors.forename: Johanna
authors.initials: J
authors.lastname: Baare
authors.affiliation: Department of Phoniatrics and Pedaudiology, Muenster University Hospital, Muenster, Germany.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Brinkheetker
authors.affiliation: Department of Phoniatrics and Pedaudiology, Muenster University Hospital, Muenster, Germany.
authors.forename: Antoinette
authors.initials: A
authors.lastname: Am Zehnhoff-Dinnesen
authors.affiliation: Institute for Biomagnetism and Biosignalanalysis, Muenster University Hospital, Muenster, Germany.|Department of Otorhinolaryngology, Jena University Hospital, Jena, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Dobel
mesh_terms: D002675:Child, Preschool; D003054:Cochlear Implants; D003638:Deafness / Q000503:physiopathology* / Q000601:surgery; D005260:Female; D006320:Hearing Tests; D006801:Humans; D008297:Male; D013060:Speech / Q000502:physiology; D013067:Speech Perception / Q000502:physiology