Executive functions, working memory capacity and academic performance of highly able students: The mediating role of self-concept

Working memory is widely acknowledged as a core and essential executive functions. The aim was to examine the mediating role of self concept in hierarchical relationship between working memory and executive functions. This cross-sectional descriptive-analytical study was conducted. A sample of 120 intellectually gifted children (mean age = 10.77 years, SD = 0.89, 80 females; 66% and 60 males, 44%) participated in the study. A mediation model, was examined, proposing the existence of interrelations between executive functions, working memory capacity and academic performance of highly able students, and a mediated path of self-concept. Structural equation modeling (SEM), with full information maximum likelihood estimation (FIML) was used to examine bivariate correlations and the mediation model. Multiple fit indices in addition to the chi-square test statistic were used to assess model fit. The results of the full mediation structural model fit indicated that the model fit the data well, with Chi-square = 733.041, p = 0.000, Relative Chi-Sq = 1.773; GFI = 0.825, CFI = 0.917, IFI = 0.910, RMSEA = 0.052. The Goodness of-fit indices of the structural model indicated that the GFI, CFI, and IFI approached or exceeded the cutoff value of 0.90.