Distinct Origins of Two-order Hierarchical Cognitive Abilities in Human Adults

Human cognitive abilities are considerably diverse from basic perceptions to complex social behaviors. All human cognitive functions are principally categorized into a two-order hierarchy. Almost all of the first-order cognitive abilities investigated in behavioral genetics have been found to be dominantly heritable. However, the origins of the human second-order cognitive abilities in metacognition and mentalizing so far remain unclear. We here systematically compared the origins of the first-order and second-order cognitive abilities involved in the metacognition and mentalizing tasks using the classical twin paradigm on human adults. Our results demonstrated a double dissociation of the genetic and environmental contributions to the first-order and second-order cognitive abilities. All the first-order cognitive abilities involved in the metacognition and mentalizing tasks were dominantly heritable. In contrast, the shared environmental effects, rather than the genetic effects, had dominant contributions to the second-order cognitive abilities of metacognition and mentalizing in human adults. Hence, our findings suggest that human adults monitoring sensitivities in metacognition and mentalizing are profoundly sculpted by their social or cultural experiences, but less preconditioned by their biological nature.