Developmental changes in perception of nonnative vowel contrasts.

Discrimination of 2 German vowel contrasts was examined in English-learning infants of 6–8 and 10–12 mo of age using a head turn procedure. The younger infants were better able than the older infants to discriminate the nonnative contrasts, but performance at 6–8 mo was below levels that have been reported for nonnative consonant contrasts. A 2nd experiment using a habituation looking procedure showed that 4-mo-old infants discriminated both German vowel contrasts, but the 6-mo-olds could not. The findings are consistent with previous consonant work, revealing a shift from a language-general toward a language-specific pattern during the 1st yr of life. However, that shift begins earlier in development for vowels than for consonants. (PsycINFO Database Record (c) 2010 APA, all rights reserved)