Project Grant F31DC023422

HOW LANGUAGE INPUT SHAPES ASL VOCABULARY DEVELOPMENT - PROJECT SUMMARY EARLY LANGUAGE INPUT IS ESSENTIAL FOR CHILDREN'S LANGUAGE DEVELOPMENT, BUT IT REMAINS UNCLEAR HOW MUCH INPUT IS NEEDED, AND AT WHICH AGES, FOR OPTIMAL EARLY VOCABULARY DEVELOPMENT. MOST CHILDREN ARE SURROUNDED BY LANGUAGE FROM BIRTH, HEARING WORDS DURING DAILY ROUTINES AND CONVERSATIONS. FOR DEAF AND HARD OF HEARING CHILDREN, LANGUAGE EXPERIENCES CAN VARY WIDELY. SOME MAY GO THROUGH PERIODS EARLY IN LIFE WITHOUT STEADY EXPOSURE TO EITHER SPOKEN OR SIGNED LANGUAGE. CURRENT GUIDANCE SUGGESTS THAT FAMILIES CONSIDER TEACHING THEIR CHILDREN SIGN LANGUAGE AMONG THEIR COMMUNICATION OPTIONS. HOWEVER, MOST FAMILIES ARE HEARING AND DO NOT KNOW A SIGN LANGUAGE WHEN THEIR CHILD IS BORN, AND PROVIDING SIGN LANGUAGE EXPOSURE MAY BE CHALLENGING FOR PARENTS WHO THEMSELVES ARE JUST LEARNING THE LANGUAGE. SOME FAMILIES IMMERSE THEMSELVES IN SIGN LANGUAGE, WHILE OTHERS BEGIN WITH ONLY A FEW SIGNS. THIS VARIATION CREATES A RARE OPPORTUNITY TO ASK: HOW MUCH AND WHAT KIND OF EARLY LANGUAGE INPUT IS ENOUGH TO SUPPORT STRONG SIGN LANGUAGE DEVELOPMENT? THIS STUDY FOCUSES ON DEAF AND HARD OF HEARING CHILDREN WHOSE HEARING PARENTS INTRODUCED THEM TO SIGN LANGUAGE EARLY IN LIFE. THE PURPOSE OF THIS STUDY IS TO DOCUMENT THE ROLE OF LANGUAGE INPUT ON VOCABULARY DEVELOPMENT BY INVESTIGATING HOW EARLY LANGUAGE INPUT RELATES TO SIGN LANGUAGE VOCABULARY ACQUISITION. BY STUDYING THIS GROUP OF CHILDREN, WE CAN BETTER UNDERSTAND HOW DIFFERENT LANGUAGE EXPERIENCES SHAPE VOCABULARY DEVELOPMENT. THIS WILL BE ACCOMPLISHED THROUGH THREE SPECIFIC AIMS: 1) DESCRIBE THE LANGUAGE INPUT THAT CHILDREN RECEIVE IN EARLY CHILDHOOD AND HOW IT CHANGES OVER TIME. 2) IDENTIFY HOW MUCH ASL IS NEEDED TO SUPPORT EARLY ASL VOCABULARY DEVELOPMENT. 3) IDENTIFY DATA-DRIVEN PATTERNS OF EARLY LANGUAGE INPUT AND RELATE THESE INPUT PATTERNS TO THE SIZE OF A CHILD'S ASL VOCABULARY. TO DO THIS, WE WILL INTERVIEW PARENTS ABOUT THEIR CHILDREN'S EARLY LANGUAGE EXPERIENCES AND EXTRACT DETAILED INFORMATION ABOUT HOW MUCH LANGUAGE INPUT CHILDREN RECEIVED ACROSS SIGNED AND SPOKEN LANGUAGE IN THE FIRST YEARS OF LIFE. WE WILL THEN RELATE CHILDREN'S CUMULATIVE SIGN LANGUAGE INPUT TO THEIR ASL VOCABULARY. WE WILL ALSO USE A MACHINE LEARNING ALGORITHM TO IDENTIFY PATTERNS IN CHILDREN'S LANGUAGE INPUT TO SEE IF CERTAIN PROFILES OF LANGUAGE INPUT RELATE TO LARGER SIGN LANGUAGE VOCABULARIES. THESE FINDINGS WILL OFFER BOTH SCIENTIFIC AND PRACTICAL VALUE. SCIENTIFICALLY, THEY WILL DEEPEN OUR UNDERSTANDING OF HOW LANGUAGE DEVELOPS WHEN INPUT VARIES. PRACTICALLY, THEY WILL ALSO PROVIDE MUCH-NEEDED GUIDANCE FOR FAMILIES AND PROFESSIONALS WORKING WITH DEAF CHILDREN, HELPING THEM UNDERSTAND HOW MUCH SIGN LANGUAGE INPUT IS NECESSARY TO SUPPORT THEIR CHILD'S SIGN LANGUAGE GROWTH.