EEG Gamma Activity Varies by Gender and Executive Function but Not by Socioeconomic Status in U.S. Preschoolers

• In Event: Relations among Socioeconomic Status, Functional Brain Activity, and Neurocognitive Outcomes: Unified Framework Approaches

Abstract

Background: EEG gamma power indexes neural maturity and has been related to executive function (EF) and socioeconomic status (SES) in early childhood (Benasich et al., 2008; Cantiani et al., 2019). Despite evidence that neural correlates of EF may differ by gender (Christakou et al., 2009; Cuevas et al., 2016), reflecting sexually dimorphic brain development (Nugent et al., 2012), little is known about gender differences in gamma power. We examined gamma power differences for socioeconomically diverse preschool girls and boys in relation to three aspects of EF —working memory, sustained attention, and inhibitory control.
Methods: Children aged 4.5 to 5.5 (N=81, 47 girls) from diverse SES in the Northeastern U.S. watched a rotating screensaver while we collected EEG power measures from frontal, central, temporal, parietal, and occipital regions in the gamma (30-48 Hz) frequency band. Children then completed a visual working memory task (Simmering, 2012) and a zoo go/no-go task (Lamm et al., 2014) indexing sustained attention (go trials) and inhibitory control (no-go trials).
Results: Repeated measures ANOVA including SES as a covariate revealed that girls had lower gamma power than boys (F(1,79)=11.53, p=.001), particularly in the frontal (F(1,79)=11.13, p=.001,), central (F(1,79)=17.2, p=.001), and occipital (F(1,79)=18.56, p<.001) regions. Girls and boys did not differ in EF performance. There was a region x go trial accuracy interaction in relation to gamma (F(3.356, 254.575), with better go accuracy relating to lower gamma power in the temporal region (F(1,73)=9.32, p=.003), while no-go trials were unrelated to gamma power. Better working memory performance was also related to lower gamma power (F(1,55)=5.44, p=.022). Although better working memory was related to higher SES (r=.362, p=.001), SES was not related to gamma power.
Discussion: In the current sample of 4.5- to 5.5-year-old children, girls had lower gamma power than boys, and lower baseline gamma was related to better working memory and sustained attention. Age-related decreases in gamma power have been reported beginning at age 4 (Perone et al., 2017; Takano & Ogawa, 1998), probably indexing synaptic pruning, and gamma power has been inversely related to cognitive skills in older children (Tierney et al., 2014). Thus, lower gamma in our sample likely indexed greater neural maturity, consistent with evidence for greater neural maturity in girls from other frequency bands (Bell, 1998; Cuevas et al., 2016) and likely reflecting prenatal factors (Nugent et al., 2012).
Our results linking lower gamma to better working memory, and lower temporal gamma to better sustained attention in this U.S. preschool sample contrast with prior findings relating higher gamma power to better EF in U.S. toddlers (Benasich et al., 2008) and highly disadvantaged Pakistani preschoolers (Tarullo et al., 2017). Further, SES did not relate to gamma, in contrast to prior infant research (Tomalski et al., 2013). The relations of gamma to SES and EF may fluctuate across development and context, highlighting the need for further research to consider these factors in mapping the complex relations of gamma to gender, SES, and EF.

Authors

• Diana Carolina Lopera-Pérez, Boston University
  Presenting Author

• Ashley St. John, Boston University
  Non-Presenting Author

• Amanda R Tarullo, Boston University
  Non-Presenting Author