Beyond Magnitude: How Math Expertise Guides Number Representation

Previous studies on numeric cognition have focused primarily on magnitude, based on its role as a core feature of number knowledge. In this paper, we report the results of three experiments investigating adults’ sensitivity to properties of number apart from magnitude. In Experiment 1, we use a triadic judgment task to replicate a classic study of number properties. In Experiment 2, we compare these representations among expert and non-expert groups. In Experiment 3, we examine whether instruction can tune representation of number properties. Results indicate that the triadic comparison task is a reliable method of assessing sensitivity to number properties. We found that magnitude is difficult to suppress among non-experts, who are primarily attuned to magnitude and parity. Mathematically sophisticated participants were sensitive to a range of number properties compared with the non-expert group. We discuss implications for theories of number concepts and their relation to special populations.