Şimal Yenigüllü, Ezgi Gür, Merve Bulut, Hakan Çetinkaya, Seda Dural
Pairwise magnitude comparison requires participants to evaluate the relative magnitude of two simultaneously presented numerical stimuli, and performance is commonly indexed by the numerical distance effect. Whether this processing is affected by spatial-numerical congruency between relative numerical magnitude and relative stimulus position-specifically, an advantage for the conventional small-left/large-right arrangement-remains less clear, especially when left-right response selection is minimized. The present study examined numerical distance effects and spatial-numerical congruency in a pairwise go/no-go magnitude-comparison task. Across two experiments, participants viewed two numerical stimuli, one on the left and one on the right. They made a single central response only when the task-relevant number appeared in the instructed spatial position. Experiment 1 used Arabic digits, whereas Experiment 2 used Turkish number words. In both experiments, participants completed either a small-number or a large-number task. Robust numerical distance effects were observed in both experiments and task versions, indicating reliable access to relative numerical magnitude. In contrast, evidence for spatial-numerical congruency was limited and task-dependent. The conventional small-left/large-right arrangement did not produce a general response-time advantage, and any congruency-related patterns were limited to the small-number task. These findings suggest that pairwise go/no-go comparison reliably engages relative-magnitude processing without necessarily producing stable or general spatial-numerical congruency. The results support a distinction between access to relative magnitude and the behavioral expression of spatial-numerical congruency under specific task configurations.