Conversational speech samples were analysed over a six-year period postoper
atively for nine profoundly deaf children implanted with the Cochlear Limit
ed 22-electrode cochlear implant between ages 2-5 years. Four years post-im
plant, at least 90% of all syllables produced by each child were intelligib
le, although only one of the children (who had suffered a progressive heari
ng loss) had over 10% intelligible syllables Drier to implantation. Over th
e B-year period, the mean number of intelligible words per utterance increa
sed from 0.15 to 4.2 and the mean number of syllables (counting both intell
igible and unintelligible syllables) increased from 1.7 to 5.2, indicating
an increase in complexity as well as intelligibility. The speech samples we
re transcribed phonetically and percentage correct analyses were conducted
on the transcripts. These analyses showed a steady improvement in the perce
ntage of correctly produced monophthongs, diphthongs and consonants. There
was a corresponding rise in the percentage of words that were produced with
out phonetic errors, Following six years of implantation, the speech acquis
ition process was incomplete, although there was no evidence to suggest a p
lateau in performance.