Individual Differences in Infants' Temperament Affect Face Processing.

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.

Infants and adults represent faces differently.

This research examined how 5-, 8-, and 11-month-olds with female primary caregivers mentally represented faces using a familiarization procedure similar to real-world experience in which infants have greater exposure to female faces aged 21-39 years than other face types. We predicted infants would form weighted representations of faces (i.e., representations weighted toward the most frequently seen faces) and would more easily form weighted representations of female than male faces given their predominant experience with women (Experiments 1 and 2). We also tested adults using this familiarization procedure (Experiment 3) and predicted they would form averaged representations of faces based on data showing that preferences for averageness (the mathematical central tendency of a population) get stronger with development. Data from the three studies supported these hypotheses. Differences in how infants and adults mentally represent faces might be developmentally advantageous and such representations provide a mechanism to help explain the differential expertise in infants' and adults' face processing abilities. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Attention during Visual Preference Tasks: Relation to Caregiving and Face Recognition.

This research examined how caregiver experience (female primary caregiver or distributed caregiving with mom and dad) influenced 10-, 14-, and 16-month-olds' visual preferences and attention toward internal facial features of female-male face pairs, and how these behaviors related to novelty preferences in a face recognition task and speed and accuracy on a visual search task. In the visual preference task, infants visually preferred male faces, regardless of caregiver experience. Despite similarities in visual preferences, infants' attention toward females and males' internal facial features was related for infants with distributed caregiving only. Infants' performance across face processing tasks most often correlated for those with female primary caregivers. Results further our understanding of how infants with female primary caregivers display specialized processing of female faces, and how infants with distributed caregiving show similarities in their attention to female and male facial features.

Caregiving experience and its relation to perceptual narrowing of face gender.

This research examined whether infants tested longitudinally at 10, 14, and 16 months of age (N = 58) showed evidence of perceptual narrowing based on face gender (better discrimination of female than male faces) and whether changes in caregiving experience longitudinally predicted changes in infants' discrimination of male faces. To test face discrimination, infants participated in familiarization/novelty preference tasks and visual search tasks including female and male faces. At each age of participation, they were coded as having a female primary caregiver only or distributed caregiving experience (alternating experience with a female and male primary caregiver). Perceptual narrowing was evident for infants with a female primary caregiver, but only within the visual search task, which required location of a familiarized face among 3 novel distractor faces (exemplar-based discrimination); it was not evident within the familiarity/novelty preference task, which required discrimination between a familiarized and novel face (individual-based discrimination). Caregiving experience significantly explained individual changes in infants' ability to locate male faces during the visual search task after 10 months. These data are the first to demonstrate flexibility of the face processing system in relation to gender discrimination when there is a change in caregiver within the infants' natural environment after perceptual narrowing normally manifests. (PsycINFO Database Record

Asymmetries in infants' attention toward and categorization of male faces: The potential role of experience.

Infants typically have a preponderance of experience with females, resulting in visual preferences for female faces, particularly high attractive females, and in better categorization of female relative to male faces. We examined whether these abilities generalized to infants' visual preferences for and categorization of perceptually similar male faces (i.e., low masculine males). We found that 12-month-olds visually preferred high attractive relative to low attractive male faces within low masculine pairs only (Experiment 1) but did not visually prefer low masculine relative to high masculine male faces (Experiment 2). Lack of visual preferences was not due to infants' inability to discriminate between the male faces (Experiments 3 and 4). The 12-month-olds categorized low masculine, but not high masculine, male faces (Experiment 5). Infants could individuate male faces within each of the categories (Experiment 6). The 12-month-olds' attention toward and categorization of male faces may reflect a generalization of their female facial expertise.

Differences in Expressivity Based on Attractiveness: Target or Perceiver Effects?

A significant association exists between adults' expressivity and facial attractiveness, but it is unclear whether the association is linear or significant only at the extremes of attractiveness. It is also unclear whether attractive persons actually display more positive expressivity than unattractive persons (target effects) or whether high and low attractiveness influences expressivity valence judgments (perceiver effects). Experiment 1 demonstrated adult ratings of attractiveness were predictive of expressivity valence only for high and low attractive females and medium attractive males. Experiment 2 showed that low attractive females actually display more negative expressivity than medium and high attractive females, but there were no target effects for males. Also, attractiveness influenced expressivity valence judgments (perceiver effects) for both females and males. Our findings demonstrate that low attractive females are at a particular disadvantage during social interactions due to their low attractiveness, actual displays of negative expressivity, and perceptions of their negative expressivity.