Separate processing mechanisms for spatial-numerical compatibility and numerical-size congruity.

Across two experiments, the numerical magnitude and the physical size of single digits presented in either two (Experiment 1) or four (Experiment 2) different font sizes were judged using either horizontally and vertically (Experiment 1) or just horizontally (Experiment 2) aligned manual responses. Such a design allowed for the simultaneous examination of the size congruity effect (SiCE), the spatial-numerical association of response codes (SNARC) effect, and the more novel spatial-size association of response codes (SSARC) effect. In Experiment 1, SiCEs and SNARC effects were found that operated independently of one another but no SSARC effect occurred. In Experiment 2, separate SiCEs and SNARC effects were found when judging numerical magnitude whereas separate SiCEs and SSARC effects were found when judging physical size. As will be discussed, such findings provide important constraints on the manner in which the full set of congruency and compatibility effects between stimulus and response dimensions in such tasks may be modeled. To illustrate this point, four different versions of a general computational processing model of these effects are considered. (PsycInfo Database Record (c) 2022 APA, all rights reserved).