Vowel Identification by Listeners With Hearing Impairment in Response to Variation in Formant Frequencies
Conclusions: Both increased presentation level for NH listeners and the presence of hearing loss produced a significant change in vowel identification for this stimulus set. Major differences were observed between NH listeners and HI listeners in vowel category overlap and in the sharpness of boundaries between vowel tokens. It is likely that these findings reflect imprecise internal spectral representations due to reduced frequency selectivity.
The Influence of Auditory Acuity on Acoustic Variability and the Use of Motor Equivalence During Adaptation to a Perturbation
Conclusion: These results provide support for the mutual interdependence of speech perception and production.
Long-term Trajectories of the Development of Speech Sound Production in Pediatric CochlearImplant Recipients
Purpose: This study characterized the development of speech sound production in prelingually deaf children with a minimum of eight years of cochlear implant (CI) experience.
Method: Twenty-seven pediatric CI recipients’ spontaneous speech samples from annual evaluation sessions were phonemically transcribed. Accuracy for these speech samples was evaluated in piecewise regression models.
Results: As a group, pediatric CI recipients showed steady improvement in speech sound production following implantation, but the improvement rate declined after six years of device experience. Piecewise regression models indicated that the slope estimating the participants’ improvement rate was statistically greater than zero during the first six years post-implantation, but not after six years. The group of pediatric CI recipients’ accuracy of speech sound production after four years of device experience reasonably predicts their speech sound production after five to 10 years of device experience.
Conclusions: The development of speech sound production in prelingually deaf children stabilizes after six years of device experience, and typically approaches a plateau by eight years of device use. Early growth in speech before four years of device experience did not predict later rates of growth or levels of achievement. However, good predictions could be made after four years of device use.