Individual Differences in Infants’ Temperament Affect Face Processing

Abstract

Infants show an advantage in processing female and familiar race faces, but the effect sizes are often small, suggesting individual differences in their discrimination abilities. This research assessed whether differences in 6–10-month-olds’ temperament (surgency and orienting) predicted how they scanned individual faces varying in race and gender during familiarization and whether and how long it took them to locate the face during a visual search task. This study also examined whether infants viewing faces posing pleasant relative to neutral expressions would facilitate their discrimination of male and unfamiliar race faces. Results showed that infants’ surgency on its own or in conjunction with their orienting regularly interacted with facial characteristics to predict their scanning and location of faces. Furthermore, infants’ scanning patterns (dwell times and internal–external fixation shifts) correlated with their ability and time to locate a familiarized face. Moreover, infants who viewed faces with pleasant expressions showed better discrimination of unfamiliar race and male faces compared with infants who viewed neutral faces. Including temperament in the analyses consistently demonstrated its significance for understanding infant face processing. Findings suggest that positive interactions with other-race individuals and men might reduce processing disadvantages for those face types. Locating familiar adults in a timely manner is a crucial skill for infants to develop and these data elucidate factors influencing this ability.

Endogenous Control and Reward-Based Mechanisms Shape Infants’ Attention Biases to Caregiver Faces

“…Infants with higher Surgency scores were both more likely to orient to their caregiver's face and spent more time looking at their caregiver's face compared to the stranger's face. Although previous work related Surgency to infants' face processing more generally (Rennels et al, 2020), this is the first evidence specifically linking Surgency to infants' attention to caregivers. Given that caregivers are rewarding for infants and children (Abrams et al, 2016;Liu et al, 2019;Minagawa-Kawai et al, 2009), we interpret this result as initial evidence that infants' attention biases to caregivers may be shaped by their sensitivity to social reward value.…”

“…Infants' orienting to unfamiliar faces is shaped by age-related improvements in endogenous attention control (e.g., Frank et al, 2014;Kwon et al, 2016), but adult research has also established that multiple additional factors, including motivational salience/social reward, can drive biased orienting in adulthood (Awh et al, 2012;Luck et al, 2021;Kim et al, 2021). Although initial work has related individual differences in reward sensitivity (i.e., Surgency/Extraversion) to face processing and recognition in infancy (Rennels et al, 2020), research has yet to investigate potential reward-based mechanisms contributing to infants' attention biases to caregivers specifically.…”

Recommendations for Investigating the Cross-Category Effect Among Hispanic and Latino Populations

“…Although dwell times toward the eye region were greatest for Black faces, staying fixated toward one region could negatively affect infants’ facial recognition. In contrast, shifting attention between internal facial features and between internal and external facial features facilitates infants’ face recognition, likely because it enables them to develop a more holistic representation of those faces (e.g., Rennels et al, 2020; Xiao et al, 2015). Early indicators of differences in psychological saliency might therefore serve as precursors to the development of cross-category effects.…”