Dominance patterns in concurrent vowel recognition

Abstract

When hearers encounter multiple people speaking at the same, they can often pick out the speech of one person from the others, but the mechanisms which they use in their acoustic discrimination process are not fully understood. To look into vowel discrimination processes, this project entailed combining sound files of minimal pairs generated by synthetic speakers. As a point of departure from many similar experiments, these files were standardized for pitch and intensity. Participants were asked to select the word they heard from a list of four potential words that shared the same beginning and ending consonants, differing only in the vowel. Participants were significantly more likely to select a word if its vowel had a higher F1 than the F1 of the other vowel of the combined audio file. Higher F2 and F3 frequencies and greater movement of F1 also contributed to increased selection rates, although not as much as the F1 ratio. Participants were also asked to describe a subset of the combined sound files. That task showed similar dominance patterns, such that participants were often unaware of the presence of one of the concurrent vowels.