The acquisition of voicing contrasts in Spanish and English learning infants and children: a longitudinal study.

The production of voice-onset time (VOT) was studied in a group of Spanishand English-learning subjects at 1 and 2 years of age. Voiceonset time of initial stop consonants from canonical utterances was measured oscillographically. At one year no significant difference in VOT production was found between Spanish and English learners at any place of articulation. Mean VOT values for infants fell in the short lag range. By two years, four of the seven children in the English group and four of the children in the Spanish group showed significant evidence of having acquired the VOT distinction in stop consonants appropriate for their native language.