The Moderation of Genetic and Environmental Influences on Executive Functioning: The Role of Familism Values

• In Event: 3-117 - Incorporating Culture and Diversity in Understanding Genetic and Environmental Influences on Human Development

Integrative Statement

Many genetically informed studies rely on homogeneous samples, making it difficult to generalize to other populations (Polderman et al., 2015). Cultural genomics examines the interplay of genes, environment, and cultural processes (Causadias & Korous, 2017), elucidating how culture can influence the etiology of a given phenotype. We measured familism, an aspect of culture that is important for children’s socioemotional development (Crosnoe, 2006) and examined whether it moderated the etiology of executive functioning (EF) and effortful control in middle childhood. Households that hold familism as a core value tend to promote obedience and respect for family members (Cervantes, 2002); therefore, we hypothesized that the etiology of EF and effortful control would be moderated by Referents, Obligation, and Total Familism.
The sample was comprised of 344 twins (mean age = 8.41 years) from the Arizona Twin Project (Lemery-Chalfant et al., 2013). Primary caregivers completed the following Familism subscales from the Mexican-American Cultural Values Scale (Knight, et al., 2010): Referents (use of family to define oneself), Obligation (obligation to provide tangible support to family), Support (close family relationships), and a mean composite of the subscales. EF measures included the computerized Flanker Task (Eriksen & Eriksen, 1974) and Continuous Performance Task (Conners, 2000) that were administered in the home. Forward and Backward Digit Span was ascertained using the Weschler Intelligence Scale for Children (Wechsler, 2003). Effortful control was measured using parent-reported Attentional Focusing and Inhibitory Control subscales of the Temperament in Middle Childhood Questionnaire (Simonds & Rothbart, 2006). To index common EF, a principal components analysis was conducted with varimax rotation.
Univariate analyses indicated that differences in task-based EF could be attributed to additive genetic (A) and nonshared environmental influences (E; A estimates from 27-64%, E estimates from 36-73%), whereas broad sense heritability influenced Attentional Focusing (69%), and Inhibitory Control was influenced by genes and the shared environment (A= 61%, C=24%). In our moderation models, none of the EF tasks were moderated by familism. However, as Referents increased, the role of the shared environment for Attentional Focusing decreased (Figure 1: Δχ2(1) = 0.69, p = .41). Total Familism moderated the etiology of Attentional Focusing (Δχ2(1) = 2.84, p = .09), such that the nonshared environment increased at low levels and decreased at high levels of Total Familism.
Overall, we found that aspects of effortful control were moderated by familism values. For Attentional Focusing, as Referents increased, the role of the shared environment decreased, showing that when parents do not use the family to define oneself, there are aspects of the environment that make twins more similar on Attentional Focusing. Including the family as part of one’s identity could be protective if there are environmental factors that negatively impact children’s effortful control abilities. Although familism is traditionally endorsed by Mexican Americans, we found that familism can also be identified in other American ethnic groups. Our findings highlight that heritable phenotypes are not immutable to the environment, emphasizing the need for twin research to consider the role of culture to better understand child development.

Authors

• Gianna Rea-Sandin, Arizona State University
  Presenting Author

• Leah D. Doane, Arizona State University
  Non-Presenting Author

• Kathryn Lemery-Chalfant, Arizona State University
  Non-Presenting Author