Detailed vocalic information in Danish 20-month-olds' novel words
Anders Højen, Thierry Nazzi · University of Southern Denmark Research Portal (University of Southern Denmark) · 2010
Infants are endowed with an amazing capacity to perceive speech sounds. However, when learning new words, infants appear to not always use their perceptual capacities to their fullest. Recent research has provided conflicting evidence regarding the extent to which infants form new lexical representations with fully specified vowels. In a recent study, French 20-month-olds were able to learn two new words that differed by a single consonant but not words that differed by a single vowel, even when changing two or more phonetic features, in a name-based categorization task (Nazzi, 2005); similar results were found at 16 months with a simplified word-learning task (Havy & Nazzi, 2009). This indicated that vocalic information is given less weight than consonantal information when learning novel words. On the other hand, English 14- or 18-month-olds were sensitive to vowel mispronunciations of three features in words they had just learned, indicating some degree of phonetic specification for vowels (Mani & Plunkett, 2008). The differences could arise from the use of different methods or different languages. The present study used the simplified word-learning task to examine Danish 20-month-olds' degree of phonetic specificity for vowels when learning novel words, given that Danish has a comparatively much richer vocalic system than both French and English. On each trial, infants were taught two new word-object correspondences differing in the vowel by two phonetic features (e.g. kis vs. kus). Subsequently, a third object was given the same label as one of the first two objects, and the infant was asked to give the experimenter the similarly labeled object. The results showed that the infants picked the correct object 72% of the time, significantly exceeding chance (p < .001). This suggested that the Danish 20-month-olds were able to encode and use the two-feature difference between the minimally paired novel words.