@article{ShakiFischer2017, author = {Shaki, Samuel and Fischer, Martin H.}, title = {Competing Biases in Mental Arithmetic}, series = {Frontiers in human neuroscience}, volume = {11}, journal = {Frontiers in human neuroscience}, publisher = {Frontiers Research Foundation}, address = {Lausanne}, issn = {1662-5161}, doi = {10.3389/fnhum.2017.00037}, year = {2017}, abstract = {Mental arithmetic exhibits various biases. Among those is a tendency to overestimate addition and to underestimate subtraction outcomes. Does such "operational momentum" (OM) also affect multiplication and division? Twenty-six adults produced lines whose lengths corresponded to the correct outcomes of multiplication and division problems shown in symbolic format. We found a reliable tendency to over-estimate division outcomes, i.e., reverse OM. We suggest that anchoring on the first operand (a tendency to use this number as a reference for further quantitative reasoning) contributes to cognitive biases in mental arithmetic.}, language = {en} } @article{WiemersBekkeringLindemann2017, author = {Wiemers, Michael and Bekkering, Harold and Lindemann, Oliver}, title = {Is more always up?}, series = {Journal of cognitive psychology}, volume = {29}, journal = {Journal of cognitive psychology}, number = {5}, publisher = {Routledge, Taylor \& Francis Group}, address = {Abingdon}, issn = {2044-5911}, doi = {10.1080/20445911.2017.1302451}, pages = {642 -- 652}, year = {2017}, abstract = {It has been argued that the association of numbers and vertical space plays a fundamental role for the understanding of numerical concepts. However, convincing evidence for an association of numbers and vertical bimanual responses is still lacking. The present study tests the vertical Spatio-Numerical-Association-of-Response-Codes (SNARC) effect in a number classification task by comparing anatomical hand-based and spatial associations. A mixed effects model of linear spatial-numerical associations revealed no evidence for a vertical but clear support for an anatomical SNARC effect. Only if the task requirements prevented participants from using a number-hand association due to frequently alternating hand-to-button assignments, numbers were associated with the vertical dimension. Taken together, the present findings question the importance of vertical associations for the conceptual understanding of numerical magnitude as hypothesised by some embodied approaches to number cognition and suggest a preference for ego-over geocentric reference frames for the mapping of numbers onto space.}, language = {en} }