Vowels as phoneme detection targets

Phoneme detection experiments, in which listeners' response time to detect a phoneme target is measured, have typically used consonant targets. This paper reports two experiments in which subjects responded to vowels as phoneme detection targets. In the first experiment, targets occurred in real words, in the second in nonsense words. Response times were long by comparison with consonant targets, and error rates were high. Targets in initial syllables were responded to much more slowly than targets in second syllables. Full vowels were responded to faster and more accurately than reduced vowels in real words, but not in nonwords. Vowel duration correlated negatively with response time. We conclude that the process of phoneme detection in English is more difficult for vowels than for consonants, and vowels in words are relatively likely to be responded to on the basis of a lexical representation. We speculate that vowel detection may be less difficult in languages with sparser vowel distributions than English.