Size before numbers: Conceptual size primes numerical value

The present work examined the influence of conceptual object size on numerical processing. In two experiments, pictures of conceptually large or small animals of equal retinal size served as prime stimuli appearing before numerically big or small integer targets. Participants were instructed to perform an unbiased parity judgment task on the target integers. When the prime's conceptual size was congruent with the target's numerical value, participants' reaction time was faster than when the two were incongruent with each other. This influence of conceptual object size on numerical value perception suggests that both types of magnitudes share similar mental representations. Our results are in accord with recent theories (e.g., Cantlon, Platt, & Brannon, 2009; Henik, Leibovich, Naparstek, Diesendruck, & Rubinsten, 2012) that emphasize the evolutionary importance of evaluation and perception of sizes to the development of the numerical system.