Approximate number sense shares etiological overlap with mathematics and general cognitive ability

Abstract

Approximate number sense (ANS), the ability to rapidly and accurately compare quantities presented non-symbolically, has been proposed as a precursor to mathematics skills. Earlier work reported low heritability of approximate number sense, which was interpreted as evidence that approximate number sense acts as a fitness trait. However, viewing ANS as a fitness trait is discordant with findings suggesting that individual differences in approximate number sense acuity correlate with mathematical performance, a trait with moderate genetic effects. Importantly, the shared etiology of approximate number sense, mathematics, and general cognitive ability has remained unexamined. Thus, the etiology of approximate number sense and its overlap with math and general cognitive ability was assessed in the current study with two independent twin samples (N = 451 pairs). Results suggested that ANS acuity had moderate but significant additive genetic influences. ANS also had overlap with generalist genetic mechanisms accounting for variance and covariance in mathematics and general cognitive ability. Furthermore, ANS may have genetic factors unique to covariance with mathematics beyond overlap with general cognitive ability. Evidence across both samples was consistent with the proposal that the etiology of approximate number sense functions similar to that of mathematics and general cognitive skills.

The nature of the association between number line and mathematical performance: An international twin study

“…However, the importance of a NUMBER LINE AND MATHEMATICS 17 basic skill does not mean that individual differences in this skill are genetically driven. Another measure of basic numerical skills, non-symbolic estimation, has shown modest influences of genetic factors in normal populations (~30%) with most of the variance explained by non-shared environmental factors (Lukowski et al, 2017;Tosto et al, 2014b). More genetically sensitive and cross-cultural research at different ages is needed to investigate possible developmental or maturational changes and the role of homogeneity/heterogeneity of the environment in the development of number line estimation.…”

Using Hierarchical Linear Models to Examine Approximate Number System Acuity: The Role of Trial-Level and Participant-Level Characteristics

“…Others have criticized this approach for not carefully accounting for all continuous dimensions ( Clayton et al, 2015 ; Gilmore et al, 2016 ). For example, images from the freely available Panamath software 1 are frequently used in the literature ( Halberda and Feigenson, 2008 ; Halberda et al, 2008 ; Libertus et al, 2011 , 2013a , b ; Mazzocco et al, 2011 ; Libertus et al, 2012 ; Fazio et al, 2014 ; Hyde et al, 2014 ; van Marle et al, 2014 ; Haist et al, 2015 ; Norris et al, 2015 ; Patalano et al, 2015 ; Purpura and Logan, 2015 ; Bugden and Ansari, 2016 ; Norris and Castronovo, 2016 ; Braham and Libertus, 2017 , 2018 ; Dillon et al, 2017 ; Lukowski et al, 2017 ; Geary et al, 2018 ), yet the software does not allow researchers to manipulate convex hull (i.e., the area of the smallest polygon that encompasses all of the dots in the set). Studies have demonstrated that convex hull is confounded with number in Panamath images, such that the more numerous set in each image typically also has a larger convex hull ( Clayton et al, 2015 ; DeWind and Brannon, 2016 ).…”

Domain-general cognitive functions fully explained growth in nonsymbolic magnitude representation but not in symbolic representation in elementary school children

“…The association between the rate of growth of ANS precision and the level of FI or PS might reflect the existence of overlap between ANS and general cognitive ability. Genetic behavioral studies revealed that there exists generalist genetic overlap among general cognitive skills and ANS [72]. In contrast with ANS, growth in NL accuracy did not vary across pupils with different levels of general cognitive predictors.…”

“…There is considerable evidence that general cognitive abilities such as fluid intelligence, processing speed and VSWM improved throughout development [70,71]. Behavioral genetic studies suggested the existence of generalist genetic overlaps between the ANS, math achievement and domain-general cognitive factors [72]. Improvement in general cognitive abilities may lead to growing precision of nonsymbolic and symbolic representations.…”