Grant: Discovery Grants Program - Individual

Statistical learning refers to the ability to track regular patterns in sensory input from ambient environments. Given its regularities and hierarchical structures, language is essentially a pattern-based system and therefore researchers have argued that statistical learning is fundamental to language acquisition. Indeed, young infants and adults can find words in artificial languages by tracking syllable co-occurrence probabilities and extracting words on that basis. However, prior studies have mainly focused on whether learners can statistically segment words from a single language; whether learners can segment words from two artificial languages remains largely unknown. Given the global prevalence of bilingualism, it is necessary to dual-input segmentation. Some studies have demonstrated that learners succeed in segmenting two overlapping artificial languages when supported by strong speaker-specific contextual cues (i.e., each language paired with a different person). However, by nature, a single bilingual individual has to alternate between two distinct languages, sometimes even in one conversation (i.e., code-switching). It is therefore important to explore whether phonetic contextual cues in a single individual's speech can facilitate adult segmentation of two artificial languages. Therefore, we will examine adult and infant learners to answer three questions: (i) Can learners make use of phonetic cues within a single individual's speech to segment words successfully from two artificial languages?; 2) Do bilinguals outperform monolinguals?; and 3) Do specific factors, such as cognitive ability or bilingual experience, underlie any potential bilingual advantage in word segmentation across two languages? In our first group of studies, we examine if adult learners generally could make use of French and English phonetic cues to segment words from two overlapping artificial languages. Pilot data indicated limitations based on certain phonemes and a simultaneous bilingual advantage. We therefore propose to test simultaneous multilinguals, use more salient phoneme differences, and use non-native phonetic cues across a series of experiments to fully explore adults' flexibility in processing information in new environments and their sensitivity to subtle cues that mark the changes of language inputs. Further, we will explore if adults' cognitive abilities are related to learners' segmentation performance. In the second set of studies, we will test infants of 9, 11, and 13 months on the same French-accented versus English-accented artificial language stimuli in a dual input segmentation task adapted for infants. This developmental approach will test if any bilingual advantages emerge in infancy. Further, we will again test cognitive skills using a executive functioning task to explore any relationship between segmentation and cognitive ability.