General Intelligence (g), ACT Scores, and Theory of Mind: (ACT)g Predicts Limited Variance Among Theory of Mind Tests

Abstract This study is the first to examine relations between general intelligence ( g ), non- g factors, and theory of mind (ToM) using structural equation modeling with multiple indicators of g and ToM. g was based on the subtests of the ACT, a college admissions test that is strongly g loaded, and ToM was based on the Reading the Mind in the Eyes Test and the Short Story Test (SST). g correlated strongly with a latent ToM factor (β = .65) and moderately with the two ToM tests (β ≈ .34), which correlated modestly with each other (β = .27). The modest correlation between the ToM tests indicates that g predicted a small amount of variance among the ToM tests (7%) and suggests that the ToM tests had little in common. In addition, non- g residuals of the ACT subtests, obtained after removing g , correlated negligibly with the ToM factor and the ToM tests (|β|  g effects suggest that g -ToM relations were attributable to “not much more than g .” The results replicated with different combinations of ACT subtests, controls for possible confounds (reading comprehension on the SST), and another college admissions test (the SAT). The use of a convenience sample (college students) and the limited measures of g and ToM are discussed as limitations. Future research should examine the robustness of effects using different measures of g and ToM and also examine possible mediators of g -ToM relations (e.g., executive functions).