A. C. Walley
J. E. Flege
L. A. Randazza
Depts. of Psychol. and Biocommun., Univ. of Alabama at Birmingham, Birmingham, AL 35294-1170
Monolingual, English-speaking 5-year-olds, 9-year-olds, and adults heard stimuli from two ``native,'' synthetic continua, in which the vowels ranged from English /(small capital eye)/ to /i/ in the context /b_b/ or /b_p/. Thus the endpoints of the first continuum constituted a word and a nonword (``bib'' vs *``beeb''); the reverse held for the second continuum (*``bip'' vs ``beep''). Other subjects heard stimuli from two ``foreign'' continua, where the vowels ranged from English /(small capital eye)/ to a foreign vowel /(small capital why)/ in the contexts described above. Thus the endpoints of the first continuum corresponded to a word and a nonword (``bib'' vs *``bYb''); both endpoints of the second continuum corresponded to nonwords (*``bip'' vs *``bYp''). After training on endpoints, subjects' identifications of the nine stimuli of a given continuum were examined to assess whether: children, like adults, exhibit a ``lexical bias'' effect for familiar vowels (from the ``native'' continua); vowel categories not bounded by another native vowel (as in the ``foreign'' continua) expand outward or become better defined with increasing age and/or lexical status.