Theories on the mechanisms of phoneme identification generally involve only the actual segment and the transitions to and from neighbouring segments. In two listening experiments we tested the importance for vowel and consonant identification of the presence of speech segments beyond the transition parts. The results clearly show that identification continues to improve when speech is added beyond the boundaries of the transitions to neighbouring phonemes. Adding speech in front of the target segment improved identification more than adding speech at the back of the target segment, even if the sound added in front was actually not part of the target phoneme itself. We also show that the identification of consonantal segments depends on the correct identification of the vowel, and vice versa, in CV-type stimuli, but not in VC-type stimuli. From these results, we conclude that context beyond the CV- and VC-transitions is used for both consonant and vowel identification.
Bibliographic reference. Son, Rob J. J. H. van / Pols, Louis C. W. (1995): "The influence of local context on the identification of vowels and consonants", In EUROSPEECH-1995, 967-970.