Our research explores fundamental questions about the development of communication and language in the first years of life. To find answers, we rely on several different kinds of research designs and procedures, ranging from engaging but carefully controlled experimental studies in our laboratories at Stanford and in East Palo Alto, to naturalistic studies of parent-infant communication based on home observations in the community.

Our research is not clinical in nature, and we do not do assessments of individual infants; rather, our goal is to understand how language abilities emerge in young children and how early language processing skills relate to children's developing linguistic and cognitive abilities later in life.

We study children learning English or Spanish as a first language, as well as children who are learning both English and Spanish at the same time.

Here are some of the fascinating and challenging questions that motivate our research:

Adults can understand spoken language with phenomenal speed and efficiency, processing 20-30 speech sounds per second in normal conversation. As infants begin learning language one word at a time,  how and when do they become "fluent listeners" able to comprehend meanings in rapid speech?

Do infants growing up hearing different languages learn to listen to speech in different ways? One small example: An English-learning child hears the all-purpose article the before nouns in both singular and plural forms, while the Spanish-learning child hears four different versions of the comparable article (la, el, las, or los), depending on whether the noun is feminine or masculine, singular or plural. As speech unfolds rapidly in time, can Spanish-learning infants take advantage of these distinctions unavailable in English to predict what kind of word is coming next?

Some of our studies explore relations between language understanding and other skills. How does becoming a “fluent listener” relate to children’s competence in other areas, for example, grammatical development, working memory)? Do children who have difficulty understanding or using words show particular difficulties with spoken language understanding? By learning more about how children understand spoken language, we hope to develop tools for early identification and evidence for intervention practices for children with language delays.