Same, but Different: Sequential and Simultaneous Fraction Comparison Tasks Elicit Different Distance and Congruency Effects
Abstract
How humans process fractions is a topic of debate in numerical cognition research. While some studies suggest that humans process the holistic magnitude of fractions, others suggest we process only the fraction components (numerators and denominators). Two cognitive effects present in fraction processing data have shaped this debate: the distance effect (better performance with fractions separated by a far numerical distance) and the congruency effect (better performance when individual numbers are larger in the larger fraction). In a study with 160 young adults, we compared distance and congruency effects across two task formats of fraction comparisons, using simultaneous and sequential presentation of stimuli. Results revealed that the distance effect and the congruency effect were stronger in the simultaneous task than in the sequential task. These findings suggest that participants used both holistic and componential strategies when comparing fractions and highlight that task formats should not be used interchangeably.