Mapping non-native pitch contours to meaning: Perceptual and experiential factors

Infants show interesting patterns of flexibility and constraint early in word learning. Here, we explore perceptual and experiential factors that drive associative learning of labels that differ in pitch contour. Contrary to the salience hypothesis proposed in Experiment 1, English-learning 14-month-olds failed to map acoustically distinctive level and dipping labels to novel referents, even though they discriminated the labels when no potential referents were present. Conversely, infants readily mapped the less distinctive rising and dipping labels. In Experiment 2, we found that the degree of pitch variation in labels also does not account for learning. Instead, English-learning infants only learned if one of the labels had a rising pitch contour. We argue that experience with hearing and/or producing native language prosody may lead infants to initially over-interpret the role rising pitch plays in differentiating words. Together, our findings suggest that multiple factors contribute to whether specific acoustic forms will function as candidate object labels.