Makeba Parramore Wilbourn

Early Communicative Gestures Prospectively Predict Language Development and Executive Function in Early Childhood

Using an epidemiological sample (N = 1,117) and a prospective longitudinal design, this study tested the direct and indirect effects of preverbal and verbal communication (15 months to 3 years) on executive function (EF) at age 4 years. Results indicated that whereas gestures (15 months), as well as language (2 and 3 years), were correlated with later EF (φs ≥ .44), the effect was entirely mediated through later language. In contrast, language had significant direct and indirect effects on later EF. Exploratory analyses indicated that the pattern of results was comparable for low- and not-low-income families. The results were consistent with theoretical accounts of language as a precursor of EF ability, and highlighted gesture as an early indicator of EF.

Attentional dynamics of infant visual foraging

Young infants actively gather information about their world through visual foraging, but the dynamics of this important behavior is poorly understood, partly because developmental scientists have often equated its essential components, looking and attending. Here we describe a method for simultaneously tracking spatial attention to fixated and nonfixated locations during free looking in 12-week-old infants using steady-state visual evoked potentials (SSVEPs). Using this method, we found that the sequence of locations an infant inspects during free looking reflects a momentary bias away from locations that were recently the target of covert attention, quickly followed by the redirection of attention—in advance of gaze—to the next target of fixation. The result is a pattern of visual foraging that is likely to support efficient exploration of complex environments by facilitating the inspection of new locations in real time.

The Lexical Stroop Sort (LSS) picture-word task: A computerized task for assessing the relationship between language and executive functioning in school-aged children

The relationship between language development and executive function (EF) in children is not well understood. The Lexical Stroop Sort (LSS) task is a computerized EF task created for the purpose of examining the relationship between school-aged children’s oral language development and EF. To validate this new measure, a diverse sample of school-aged children completed standardized oral language assessments, the LSS task, and the widely used Dimensional Change Card Sort (DCCS; Zelazo, 2006) task. Both EF tasks require children to sort stimuli into categories based on predetermined rules. While the DCCS largely relies on visual stimuli, the LSS employs children’s phonological loop to access their semantic knowledge base. Accuracy and reaction times were recorded for both tasks. Children’s scores on the LSS task were correlated with their scores on the DCCS task, and a similar pattern of relationships emerged between children’s vocabulary and the two EF tasks, thus providing convergent validity for the LSS. However, children’s phonological awareness was associated with their scores on the LSS, but not with those on the DCCS. In addition, a mediation model was used to elucidate the predictive relationship between phonological awareness and children’s performance on the LSS task, with children’s vocabulary fully mediating this relationship. The use of this newly created and validated LSS task with different populations, such as preschoolers and bilinguals, is also discussed.

Relations Between Vocabulary and Executive Functions in Spanish–English Dual Language Learners

The role of dual language exposure in childrens cognitive development continues to be debated. The majority of the research with bilingual children in the US has been conducted with children becoming literate in only one of their languages. Dual language learners who are becoming literate in both their languages are acutely understudied. We compared dual language learners (n = 61) in a Spanish–English dual language immersion program to monolingual English speaking children (n = 55) who were in a traditional English only school. Children (kindergarten to 3rd grade) completed standardized vocabulary tasks and two measures of executive functions. Despite having significantly smaller English vocabularies, the dual language learners outperformed the monolingual children on the executive function measures. Implications for our understanding of the relations between oral language development and executive function in bilingual children are discussed.

Constructing Emotion Categorization: Insights From Developmental Psychology Applied to a Young Adult Sample.

Previous research has found that the categorization of emotional facial expressions is influenced by a variety of factors, such as processing time, facial mimicry, emotion labels, and perceptual cues. However, past research has frequently confounded these factors, making it impossible to ascertain how adults use this varied information to categorize emotions. The current study is the first to explore the magnitude of impact for each of these factors on emotion categorization in the same paradigm. Participants (N = 102) categorized anger and disgust emotional facial expressions in a novel computerized task, modeled on similar tasks in the developmental literature with preverbal infants. Experimental conditions manipulated (a) whether the task was time-restricted, and (b) whether the labels “anger” and “disgust” were used in the instructions. Participants were significantly more accurate when provided with unlimited response time and emotion labels. Participants who were given restricted sorting time (2s) and no emotion labels tended to focus on perceptual features of the faces when categorizing the emotions, which led to low sorting accuracy. In addition, facial mimicry related to greater sorting accuracy. These results suggest that when high-level (labeling) categorization strategies are unavailable, adults use low-level (perceptual) strategies to categorize facial expressions. Methodological implications for the study of emotion are discussed.

Developmental Changes in Infants' Categorization of Anger and Disgust Facial Expressions.

For decades, scholars have examined how children first recognize emotional facial expressions. This research has found that infants younger than 10 months can discriminate negative, within-valence facial expressions in looking time tasks, and children older than 24 months struggle to categorize these expressions in labeling and free-sort tasks. Specifically, these older children, and even adults, consistently misidentify disgust expressions as anger. Although some scholars have hypothesized that young infants would also be unable to categorize anger and disgust expressions, this question has not been empirically tested. In addition, very little research has examined developmental changes in infants’ perceptual categorization abilities with high arousal, within-valence emotions. For this reason, the current study tested 10- and 18-month-olds in a looking time task and found that both age groups could perceptually categorize anger and disgust facial expressions. Furthermore, 18-month-olds showed a heightened sensitivity to novel anger expressions, suggesting that, over the second year of life, infants’ emotion categorization skills undergo developmental change. These findings are the first to demonstrate that young infants can categorize anger and disgust facial expressions and to document how this skill develops and changes over time.