What's in a smile?

Abstract

In positive social contexts, both adults and older infants show more Duchenne smiling (which involves high cheek raising) than non-Duchenne smiling (which does not). This study compared Duchenne and non-Duchenne smiles in early infancy for clues to their emotional significance. Infants (N = 13) from 1 to 6 months of age were videotaped weekly for 5 min in 208 face-to-face interactions with their mothers. Levels of Duchenne and non-Duchenne smiling were correlated within interactive sessions, and the 2 smiles had similar developmental trajectories. Duchenne smiles were typically preceded by non-Duchenne smiles. The results suggest these frequently contrasted types of smiles occur in similar situations and are often different temporal phases of a continuous emotional process. In contrast to adults, infant Duchenne smiles had longer durations than non-Duchenne smiles, suggesting infant smiling does not fit adult models of emotional functioning.

Infant Affect During Parent—Infant Interaction at 3 and 6 Months: Differences Between Mothers and Fathers and Influence of Parent History of Depression

“…As reported in other studies of mother-infant interaction (e.g., Malatesta & Haviland, 1982;Messinger, Fogel, & Dickson, 1999), infants' positive affect increased from 3 to 6 months. We also found indirect evidence that negative affect was decreasing.…”

Empirical investigation of the temporal relations between speech and facial expressions of emotion

“…lower than the average recognition rate) for expressions of fear, surprise, and disgust (see Table 3 for a summary of our design recommendations to enhance recognition of emotions by users). Furthermore, the expression of disgust is a noteworthy exception to the good performance of the "end of speech" condition: The temporal pattern also influenced the perceived intensity of emotions, but in a different way: the "during speech" condition resulted in higher perceived intensity, which can be attributed to the total duration of the facial expression -in the "during speech" condition the facial expression was twice as long as in all other conditions -and is consistent with existing literature suggesting that duration and intensity are correlated in the generation [23] and perception [25] of facial expressions. However, variations in the duration of facial expressions constitute a limitation of our study and would require a new experimental iteration in order to be better understood: in particular, we wonder whether they might introduce biases in the evaluation of realism since the correlation matrix showed that realism was strongly correlated to intensity of the stimuli.…”

Detecting bids for eye contact using a wearable camera

“…Eye contact is a powerful social signal and plays a crucial role in regulating social interactions from the first months of life [17]. Before they are able to speak, infants and toddlers communicate with others using well-timed looks coordinated with gestures and vocalizations [26], [14]. Eye contact also plays a key role in joint attention, used to denote a class of behaviors in which children use gaze and gesture to spontaneously create or indicate a shared point of reference with another person [28].…”