Natural vowel and consonant recognition by Laura cochlear implantees

Objective: This study was performed to examine whether spectral and tempora l properties of speech sounds are transferred effectively by the Laura coch lear implant device, and to determine whether listeners with different leve ls of performance use the same type of information to understand speech. Design: Twenty-five adult Laura cochlear implantees identified 12 repetitio ns of 10 vowels in /hVt/ utterances and 16 consonants placed in intervocali c /a/ context. The stimulus-response confusion matrices were analyzed in te rms of relative information transmission scores (Miller & Nicely, 1955), an d they were subjected to multidimensional INDSCAL analyses to examine wheth er a similar pattern of results would emerge when no prior assumptions were made about the division of categories. Results: To examine perception for different levels of performance, the vow el and consonant confusion data were divided into three groups of subjects: the better, intermediate, and poorer performers. In general, the INDSCAL a nalyses confirmed the results obtained from the information transmission an alyses. However, they also supplemented it with other perceptually relevant cues for cochlear implantees, as web as with the weightings over different perceptual dimensions for different types of performers. These analyses su ggest that although all subjects use the same type of information, the bett er performers are more capable of using these different cues than poor perf ormers.