Infants are born highly sensitive to the natural patterns found in languages. They use their perceptual sensitivity to acquire detailed information about the structure of languages in their environment. To date, most studies of infant perception and early language acquisition have investigated spoken/auditory languages and hearing infants (e.g.…

This dissertation investigated the caregiving relationships between infants and nonparental caregivers in early childcare settings through the lens of attachment and language behaviors. This study sought to provide an opportunity to extend our understanding of the socioemotional factors that influence children's development in their daily lives.…

The present dissertation extracted 17,291 questions from Aki, Ryo, and Tai and their mother's spontaneously produced speech data available in the CHILDES database (MacWhinney, 2000; Oshima-Takane & MacWhinney, 1998). The children's age ranged from 1;3 to 3;0. Their questions were coded for (1) yes/no questions that include a sentence-final…