Abstract

Many studies suggest that numerical stimuli automatically activate a spatially oriented mental number line. This representation would be involved in the compatibility effect between numerical magnitude and response side (SNARC effect). In this study we employed hierarchical stimuli, in which the numerical information was either at the relevant or irrelevant level, to investigate the automaticity assumption. The SNARC effect, indexing access to numerical magnitude, was found only when numerical information was task-relevant.