In this dissertation, I examine whether infants’ experience with their native language guides their developing expectations about the nature of an appropriate label for an object and the context in which these biases constrain their associative word learning ability.
Chapter 2 examines whether infants’ preference for words as object labels is impacted by native-language phonotactics and/or the phonetic realizations of native language sound categories (phonemes). Across two studies, 12-month-olds’ acquisition of novel English word-object pairings were compared to their acquisition of forms that violate native-language phonotactics (Czech) or forms that violate the low-level phonetic realization of phonemes (Japanese). Results indicate that infants are beginning to apply their language-specific knowledge to their acceptance of word forms and thus, will not map words that violate the phonotactics of their native language to objects.
Chapter 3 examines whether 12-month-olds will treat content versus function word forms differently in a sound-object associative task. Results indicate that 12-month-olds distinguish between different types of word forms on the basis of their phonological and acoustic properties and use this knowledge to guide their expectations about the appropriate word form for an object label.
Chapter 4 examines whether infants will override their bias for specific words as object labels when provided with a training phase that clarifies the referential role of these labels. Infants’ mappings of three different types of forms to objects in a modified referential Switch task were compared: phonotactically illegal CCVC words, consonantal sounds, and novel function-like words. Results indicate that infants will demonstrate flexibility in the types of linguistic forms they will map to objects, however, this flexibility appears to be constrained to structural well-formed words that share the structural properties of noun-like words, even when the referential role of these labels are clarified.
These findings demonstrate that infants rely on the sound properties of the to-be-learned label to determine whether it is an appropriate label for an object, namely, a phonotactically legal content-like word. Furthermore, when provided with an additional cue that clarifies the purpose of the Switch task, infants can weigh this information along with the linguistic properties of the label to help guide their word-object mappings.