Relative roles of consonants and vowels in perceiving phonetic versus talker cues in speech

Abstract

Perceptual experiments tested whether consonants and vowels differentially contribute to phonetic versus indexical cueing in speech. In 2 experiments, 62 total participants each heard 128 American–English word pairs recorded by 8 male and 8 female talkers. Half the pairs were synonyms, while half were nonsynonyms. Further, half the pairs were words from the same talker, and half from different, same-sex talkers. The first word heard was unaltered, while the second was edited by setting either all vowels (‘‘Consonants-Only’’) or all consonants (‘‘Vowels-Only’’) to silence. Each participant responded to half Consonants-Only and half Vowels-Only trials, always hearing the unaltered word once and the edited word twice. In experiment 1, participants judged whether the two words had the same or different meanings. Participants in experiment 2 indicated whether the word pairs were from the same or different talkers. Performance was measured as latencies and d values, and indicated significantly greater sensitivity to phonetic content when consonants rather than vowels were heard, but the converse when talker identity was judged. These outcomes suggest important functional differences in the roles played by consonants and vowels in normative speech.