Bilingualism, Late Talkers, Network Science, Vocabulary Acquisition
Conditions
Keywords
bilingualism, late talkers, parent input, toddlers, word learning, vocabulary
Brief summary
The goal of this clinical trial is to understand how different types of word categories, along with the language children hear from their parents, support bilingual toddlers' word learning. This study will address two main questions: (1) How are the words toddlers know related to the words their parents use? and (2) How does what toddlers already know help them learn new words in two languages? The investigators will compare bilingual toddlers with typical development to those with language delay to determine whether they learn new words in similar ways. Children's vocabulary knowledge will be assessed using standardized parent-report checklists. To examine how different types of categories support learning, the study will focus on two early-acquired categories: animals and clothing. The investigators will compare what parents report about their children's vocabulary with how children learn new words within each category. To understand the role of parent input, children and their parents will engage in shared book reading and play activities using materials from one of the target categories. Parent-child interactions will be video recorded. Children will also complete an eye-tracking task in which they learn new words in two languages within the same category.
Interventions
Participants will learn new words that refer to objects that belong to a category from which toddlers know many words (i.e., animals). They will learn new animal words in two different language conditions: a single language context and a dual language context. In the single language context, they will learn new English-like words in a learning environment where they only hear one language (i.e., English). In the dual language context, they will learn new English-like and Spanish-like words in a learning environment where they only hear both languages. Participants and their parents will also read books about animals and play with animal toy sets.
Participants will learn new words that refer to objects that belong to a category from which toddlers know few words (i.e., clothing). They will learn new clothing words in two different language conditions: a single language context and a dual language context. In the single language context, they will learn new English-like words in a learning environment where they only hear one language (i.e., English). In the dual language context, they will learn new English-like and Spanish-like words in a learning environment where they only hear both languages. Participants and their parents will also read books about clothes and play with toy sets that include clothing.
Sponsors
Study design
Intervention model description
A mixed-factor design where each child will be randomly assigned to one of two word learning conditions (animal or clothing). Within each condition, children will learn words in single and dual language conditions. The clinical group (toddlers with late talking) is compared to the control group (toddlers with typical development) on these conditions.
Eligibility
Inclusion criteria
* At least 10% exposure to both English and Spanish or at least 90% exposure to English and another language
Exclusion criteria
* Hearing impairment * Uncorrected visual impairment * Neurological impairment * Genetic syndromes * Neurodevelopmental disabilities (e.g. autism) * More than 10% exposure to a language other than English or Spanish
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Word learning | Day 1 | The researchers will assess learning through participants' looking behavior via experimental eye-tracking paradigms. Specifically, the researchers will measure how accurately and quickly participants look to the target object after hearing its name. |
| Vocabulary Network Properties | Day 1 | The researchers will characterize participants' vocabulary size and structure using the MacArthur-Bates Communicative Development Inventories (MB-CDI). Vocabulary size will be calculated using the raw number of words produced (range: 0-680 words) and their age-matched percentile score from the MB-CDI (range: 0-100). Higher scores indicate larger vocabulary sizes.The researchers will also calculate how many words each participant knows in in two categories on the MB-CDI (i.e., animals \[0-43 words\] and tools \[0-28 words\]) across the languages they are learning (i.e., English and Spanish). Network properties may include the number of words in a category and the number of connections between words in a category. |
| Parent Language Input | Day 1 | The researchers will calculate the number of words the parent says to their child during book reading and toy play activities. Language input will be defined as the total number of nouns and verbs (tokens) and the number of unique nouns and verbs (types). |
Countries
United States