Psychology Science Quarterly, Volume 50, 2008 (4), pp. 489-525 On the cognitive link between space and number: a meta-analysis of the SNARC effect GUILHERME WOOD 1 , KLAUS WILLMES 2 , HANS-CHRISTOPH NUERK 1 & MARTIN H. FISCHER 3 Abstract An association of numbers and space (SNARC effect) has been examined in an ever growing litera- ture. In the present quantitative meta-analysis, 46 studies with a total of 106 experiments and 2,206 participants were examined. Deeper number magnitude processing determined by task, stimulus and participants characteristics was associated with a stronger SNARC effect. In magnitude classification tasks the SNARC effect assumed consistently a categorical shape. Furthermore, the SNARC effect was found to increase with age from childhood to elderly age. No specific difference in the size of the SNARC effect was observed due to the explicit use of imagery strategies that could not be explained by increased reaction times. In general, these results corroborate the predictions by the dual-route model of the SNARC effect regarding the activation of number magnitude representation and suggest that auto- maticity may play a role in the development of the association of numbers and space across the life- span. Key words: SNARC, mental number line, aging, imagery, meta-analysis 1 Dr. Guilherme Wood, Department of Psychology, Paris-Lodron University of Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria; Tel.: 0043 662 8044 5163, Fax: 0043 662 8044 188, email: guilherme.wood@sbg.ac.at 2 Department of Neurology/Section Neuropsychology, University Hospital RWTH-Aachen 3 School of Psychology, University of Dundee, Scotland UK