SPEEDED DETECTION OF VOWELS - A CROSS-LINGUISTIC STUDY

In four experiments, listeners' response times to detect vowel targets in spoken input were measured. The first three experiments were condu cted in English. In two, one using real words and the other, nonwords, detection accuracy was low, targets in initial syllables were detecte d more slowly than targets in final syllables, and both response time and missed-response rate were inversely correlated with vowel duration . In a third experiment, the speech context for some subjects included all English vowels, while for others, only five relatively distinct v owels occurred. This manipulation had essentially no effect, and the s ame response pattern was again observed. A fourth experiment, conducte d in Spanish, replicated the results in the first three experiments, e xcept that miss rate was here unrelated to vowel duration. We propose that listeners' responses to vowel targets in naturally spoken input a re effectively cautious, reflecting realistic appreciation of vowel va riability in natural context.