How do spatial representations enhance cognitive numerical processing?

Several philosophical theories attempt to explain how actions performed in the world enhance cognitive processing: internalism, active externalism, and cognitive integration. The aim of this paper is to examine whether the use of spatial representations in arithmetic can shed light on this debate. Relying on philosophical analysis, on a discussion of empirical work in the cognitive neuroscience of number, and on a historical case study, I will show that spatial representations of number indicate an integration between internal and external cognitive processes.     

Spatial orienting in the visual field: a unified perceptual space?

Visual attention can be oriented toward a spatial location in the visual field exogenously by an abrupt onset of a peripheral cue. In a series of behavioral studies on exogenous orienting of attention with a double-cue paradigm, we demonstrated a functional subdivision of perceptual space in the visual field. Specifically, inhibition of return (IOR) is much stronger at periphery relative to perifoveal visual field up to approximately 15° eccentricity, suggesting two dissociable functional areas in the visual field. To further investigate the generality of this functional subdivision of the visual field, we measured IOR effects with another single-cue paradigm and applied a very short cue-target interval that was typically anticipated not to observe any inhibitory effect at all. Consistent with this expectation, no IOR effects at the eccentricities up to 15° were observed. However, significant IOR effects beyond 15° eccentricities were consistently demonstrated. These results not only revealed an early onset of IOR for more peripheral stimuli, but also confirmed that the perceptual space in the visual field is not homogeneous but underlies a functional subdivision with a border of ca. 15° eccentricity.