A Multilab Study of Bilingual Infants: Exploring the Preference for Infant-Directed Speech

From the earliest months of life, infants prefer listening to and learn better from infant-directed speech (IDS) compared with adult-directed speech (ADS). Yet IDS differs within communities, across languages, and across cultures, both in form and in prevalence. This large-scale, multisite study used the diversity of bilingual infant experiences to explore the impact of different types of linguistic experience on infants’ IDS preference. As part of the multilab ManyBabies 1 project, we compared preference for North American English (NAE) IDS in lab-matched samples of 333 bilingual and 384 monolingual infants tested in 17 labs in seven countries. The tested infants were in two age groups: 6 to 9 months and 12 to 15 months. We found that bilingual and monolingual infants both preferred IDS to ADS, and the two groups did not differ in terms of the overall magnitude of this preference. However, among bilingual infants who were acquiring NAE as a native language, greater exposure to NAE was associated with a stronger IDS preference. These findings extend the previous finding from ManyBabies 1 that monolinguals learning NAE as a native language showed a stronger IDS preference than infants unexposed to NAE. Together, our findings indicate that IDS preference likely makes similar contributions to monolingual and bilingual development, and that infants are exquisitely sensitive to the nature and frequency of different types of language input in their early environments

A multilab study of bilingual infants: Exploring the preference for infant-directed speech

From the earliest months of life, infants prefer listening to and learn better from infant-directed speech (IDS) compared with adult-directed speech (ADS). Yet IDS differs within communities, across languages, and across cultures, both in form and in prevalence. This large-scale, multisite study used the diversity of bilingual infant experiences to explore the impact of different types of linguistic experience on infants’ IDS preference. As part of the multilab ManyBabies 1 project, we compared preference for North American English (NAE) IDS in lab-matched samples of 333 bilingual and 384 monolingual infants tested in 17 labs in seven countries. The tested infants were in two age groups: 6 to 9 months and 12 to 15 months. We found that bilingual and monolingual infants both preferred IDS to ADS, and the two groups did not differ in terms of the overall magnitude of this preference. However, among bilingual infants who were acquiring NAE as a native language, greater exposure to NAE was associated with a stronger IDS preference. These findings extend the previous finding from ManyBabies 1 that monolinguals learning NAE as a native language showed a stronger IDS preference than infants unexposed to NAE. Together, our findings indicate that IDS preference likely makes similar contributions to monolingual and bilingual development, and that infants are exquisitely sensitive to the nature and frequency of different types of language input in their early environments

Do Bilingual Infants Possess Enhanced Cognitive Skills?

Prior studies have reported that bilingualism enhancescognitive ability due to the regular conflict management oftwo language systems (Bialystok, 2015). Here, we explorewhether infant bilingualism improves cognitive ability at 9.5months. Twenty-four monolingual English and 23 bilingualFrench-English infants were first trained to predict a rewardon the right based on a set of tone-shape rule structure (AABpattern). Infants were later trained to predict a differentreward on the left based on another set of new rule structure(ABB pattern). Correct anticipation of reward locationsindicates successful learning. If bilingualism improvesinfants’ cognitive skills, bilingual infants would be better atlearning a new pattern-reward association. However, we didnot find evidence that bilinguals looked at the correct locationmore than monolinguals or learned the new pattern-rewardassociation faster. Thus, our results suggest bilingualism maynot enhance cognitive ability at 9.5 months, as least using thecurrent paradigm

Should we always log-transform looking time data in infancy research?

Researchers often measure infants looking time (LT) as a dependent variable to measure how infants pay attention to certainstimuli. Using a large repository of data from their lab and the literature, Csibra and colleagues (2016) reported that thedistribution of LT is positively skewed and thus proposed that researchers should log-transform LT before running anyparametric analysis. In this study, we investigated whether log-transformation of LT will make the distribution normallydistributed by using data from a large-scale replication infancy study (ManyBabies Consortium (MB1), in press). Further,we simulated positively skewed LT data to examine whether log-transformation of LT would improve power. We foundthat log-transformation of the MB1 LT data did not make the LT data normally distributed. Also, we found that log-transformation of LT only slightly increased power. Implications and benefits of log-transformation of LT data will bediscussed

A Multilab Study of Bilingual Infants: Exploring the Preference for Infant-Directed Speech

From the earliest months of life, infants prefer listening to and learn better from infant-directed speech (IDS) compared with adult-directed speech (ADS). Yet IDS differs within communities, across languages, and across cultures, both in form and in prevalence. This large-scale, multisite study used the diversity of bilingual infant experiences to explore the impact of different types of linguistic experience on infants’ IDS preference. As part of the multilab ManyBabies 1 project, we compared preference for North American English (NAE) IDS in lab-matched samples of 333 bilingual and 384 monolingual infants tested in 17 labs in seven countries. The tested infants were in two age groups: 6 to 9 months and 12 to 15 months. We found that bilingual and monolingual infants both preferred IDS to ADS, and the two groups did not differ in terms of the overall magnitude of this preference. However, among bilingual infants who were acquiring NAE as a native language, greater exposure to NAE was associated with a stronger IDS preference. These findings extend the previous finding from ManyBabies 1 that monolinguals learning NAE as a native language showed a stronger IDS preference than infants unexposed to NAE. Together, our findings indicate that IDS preference likely makes similar contributions to monolingual and bilingual development, and that infants are exquisitely sensitive to the nature and frequency of different types of language input in their early environments

Peekbank: Exploring children's word recognition through an open, large-scale repository for developmental eye-tracking data

The ability to rapidly recognize words and link them to referents in context is central to children's early language development. This ability, often called word recognition in the developmental literature, is typically studied in the looking-while-listening paradigm, which measures infants' fixation on a target object (vs. a distractor) after hearing a target label. We present a large-scale, open database of infant and toddler eye-tracking data from looking-while-listening tasks. The goal of this effort is to address theoretical and methodological challenges in measuring vocabulary development. We present two analyses of the current database (N=1,320): (1) capturing age-related changes in infants' word recognition while generalizing across item-level variability and (2) assessing how a central methodological decision -- selecting the time window of analysis -- impacts the reliability of measurement. Future efforts will expand the scope of the current database to advance our understanding of participant-level and item-level variation in children's vocabulary development