Perceptual assimilation of French and German vowels by American English monolinguals: Acoustic similarity does not predict perceptual similarity

Previous research in our laboratory has demonstrated that the perceived similarity of vowels across languages is not always predictable from the closeness of their target formant values in F1/F2/F3 space. In this study, perceptual similarity was established using a task in which 11 American English (AE) monolinguals were presented multiple tokens of 9 French vowels and 14 North German vowels (in separate blocks) produced in citation‐form /hVb(a)/ (bi)syllables by native speakers. They selected 1 of 11 AE vowel responses to which each non‐native vowel token was most similar, and rated its goodness on a 9‐point Likert scale. Of special interest was the perceptual assimilation of front rounded French [y, oe] and German [y, Y, o/, oe] vowels. Acoustically, all six French and German vowels are more similar to front unrounded AE vowels. However, all six vowels were perceived to be more similar to back rounded AE vowels (range across vowels = 55% to 100%), although relatively poor exemplars. There were differences across languages in how the same vowel was assimilated (e.g., French /y/ assimilated to front AE vowels 13%, German /y/, 0%; French [oe] 3%, German [oe] 45%). There were also large individual differences in listeners assimilation patterns. [Work supported by NIDCD.]