Neural Indices of Vowel Discrimination in Monolingual and Bilingual Infants and Children.

Objectives: To examine maturation of neural discriminative responses to an English vowel contrast from infancy to 4 years of age and to determine how biological factors (age and sex) and an experiential factor (amount of Spanish versus English input) modulate neural discrimination of speech.

Design: Event-related potential (ERP) mismatch responses (MMRs) were used as indices of discrimination of the American English vowels [ε] versus [I] in infants and children between 3 months and 47 months of age. A total of 168 longitudinal and cross-sectional data sets were collected from 98 children (Bilingual Spanish-English: 47 male and 31 female sessions; Monolingual English: 48 male and 42 female sessions).

Neural mismatch indices of vowel discrimination in monolingually and bilingually exposed infants: does attention matter?

Neurophysiological studies of infant speech suggest that mismatch responses (MMRs) have predictive value for later language. Their value, however, is diminished because unexplained differences in the MMR patterns are seen across studies. The current study aimed to identify the functional nature of infant MMRs by recording event-related-potentials (ERPs) to an infrequent English vowel change in internal or final positions of a sequence of ten vowels in six-month-old monolingually and bilingually exposed infants.