Infant smiles can predict later adaptive functioning, but little is known about the temporal course of infant smiles or their perceived emotional intensity. This collaborative project combines computer-based measurements of infant smiles with parents' ratings of those smiles. The project goals are to understand how infants smile, and to document the features that make infant smiles appear more or less joyful.
To understand how infants smile, the smile strength and co-occurring mouth opening of 50 six-month-old infants' smiles will be measured using computer software (CMU/Pitt Automated Facial Image Analysis, v. IV). These objective measurements will be used to document how infant smile form, peak, and dissolve in time. That is, we will create real-time portraits of smiles to more fully understand positive emotional functioning. Statistical associations between smile strength and mouth opening will be examined, as will differences - both between smiles and between infants - in how strongly these components of smiles are associated. Complementary graphical and statistical approaches will encourage dynamic accounts of emotional functioning and new avenues of research on the role of emotion in learning and development.
The project uses rating studies to document features that make infant smiles appear more or less joyful. Both parents of infants and undergraduates will be asked to rate the emotional intensity of both still images and video clips of smiles. Automated measurements of smile strength and mouth opening will then be used to predict ratings of positive emotional intensity. Positive findings would validate automated measurements of specific features of infant smiles as indices of infant joyful emotional intensity.
In this project, leading infant emotion researchers will collaborate with a cutting-edge automated facial measurement team to investigate infants' smiles. Infants use positive facial expressions to express emotions and communicate with others. Basic knowledge of the temporal course of in vivo infant emotional expressions promises an objective view of normative and compromised emotional functioning and development. To that end, the acquired database of digitized facial expressions and their automated measurements will be made available to requesting investigators. These objective descriptions will be complemented by parental and naive observers' perceptions of the emotional intensity of these expressions. This will validate the emotional significance of the automated measurements, and contribute to the development of a tool for automated coding that has the potential for broad impact.
