In this study conducted by Goldstein et al, experimenters used birdsong in songbirds to illustrate the development of speech in humans due to their similarities. This study challenged the traditional viewpoint of human vocal development that proposed learning to talk is an outcome caused by the maturation of infants. The study suggested that maturation perspective might be too narrow as it placed too much emphasis on internal causes and implied that infants could only play an inactive role in terms of speech development. The aim of the study was to find out if the actions of the caregivers affected the vocal development of infants. Specifically, this research wants to find out if social contingency offer opportunities for infants to learn vocalization and if infants can learn from caregiver’s reactions to their sounds. …show more content…
The infants were randomly assigned to either the contingent condition (CC) or the yoked condition (YC). There were a total of 3 sessions. During these sessions, the experimenters recorded the frequency of vocalization that mothers responded to, total number of infant vocalizations, and some infraphonological parameters of the infant’s sounds. The experimenters placed infants in both conditions into two 30 minutes play session and observed both the mother and infant. The first session aided the mothers and infants to familiarize with the environment. In the second session, the experimenters controlled the contingency between mother’s responsiveness as they recorded infant’s vocal production. For example, in the CC scenario, half of the mothers had to react immediately when their infants vocalized while in the YC scenario, mothers only responded when the experimenter told them to do