Decimal numbers are generally assumed to be a straightforward extension of the base-ten system for whole numbers given their shared place value structure. However, in decimal notation, unlike whole numbers, the same magnitude can be expressed in multiple ways (e.g., 0.8, 0.80, 0.800, etc.). Here, we used a number line task with carefully selected…

Our mental representation of the infinite has received little research attention in cognitive psychology. In countably infinite sets, the infinity symbol (8) is presumed to be perceived as larger than any finite natural number. The present study sought to explore if the infinity symbol is processed as "larger than" natural numbers, and,…

The solution and verification of single-digit multiplication problems vary in speed and accuracy. The current study examines whether the number of different digits in a problem accounts for this variance. In Experiment 1, 41 participants solved all 2-9 multiplication problems. In Experiment 2, 43 participants verified these problems. In Experiment…

Although difficulties processing both symbolic and nonsymbolic proportion compared with absolute number are well established, the mechanisms involved remain unclear. We investigate four potential explanations to account for better number processing in adulthood: (a) number is more salient than proportion, (b) number is encoded more automatically…

To explain children's difficulties learning fraction arithmetic, Braithwaite et al. (2017) proposed FARRA, a theory of fraction arithmetic implemented as a computational model. The present study tested predictions of the theory in a new domain, decimal arithmetic, and investigated children's use of conceptual knowledge in that domain. Sixth and…

Little is known about the mental representation of large multidigit numbers that are usually beyond our personal experience. The present study explored the processing mechanisms of these numbers in a series of experiments, using the numerical comparison task. Experiment 1 included within and between-scale comparisons of multidigit numbers varying…

Rational numbers are represented by multiple notations: fractions, decimals, and percentages. Whereas previous studies have investigated affordances of these notations for representing different types of information (DeWolf et al., 2015; Tian et al., 2020), the present study investigated their affordances for solving different types of arithmetic…

This study reports the results of 4 experiments that addressed whether the domains of deictic time and number exert a cross-domain link. Such a link would be consistent with A Theory of Magnitude (i.e., ATOM). In contrast, no link between the two domains would support the conceptual metaphor theory (CMT), which assumes that each domain is only…

To develop theories of how comprehenders extract the message from a linguistic stream, it is critical to understand how they conceptually represent referents. The experiments reported here focus on singular collective nouns (e.g., "committee," "team"), which introduce a single group into the discourse and test whether they…

Given that both children and adults struggle with fractions in mathematics education, we investigated the processing of nonsymbolic fractions in a continuous form of part-of-the-whole. Continuous features of nonsymbolic numbers (e.g., the size of dots in an array) were found to influence numerosity judgment, but it should be noted that the…

Frequent forced switching between tasks has been shown to reduce switch costs and increase voluntary switch rates. So far, however, the boundary conditions of the influence of forced task switching on voluntary task switching are unknown. Thus, the present study was aimed to test different aspects of generalizability (across items, tasks, and…