Synthetic two-formant vowel perception by some of the better cochlear-implant patients.

Synthetic two-formant vowel recognition was tested in some of the better cochlear-implant users to determine their ability to resolve sounds that differ essentially in their frequency content. The vowels /i, epsilon, alpha, u/ were synthesized with equal duration and similar sound pressure level. The formant values were chosen to approximate the values of these vowels in French, German and American English. Performance ranged from 29 to 71% for the 6 patients with the Chorimac implant, from 25 to 67% for the 9 patients with the 3M/Vienna implant, from 63 to 92% for the 10 patients with the Nucleus implant from Hannover, from 17 to 79% for the 10 patients with the Duren/Cologne implant, from 54 to 100% for the 9 patients with the Symbion implant, and from 79 to 100% for the 10 Nucleus patients from the USA. Patients with each of these devices can utilize some spectral information when recognizing steady-state vowels.