Chapter 15 - Symbolic and Nonsymbolic Representation of Number in the Human Parietal Cortex: A Review of the State-of-the-Art, Outstanding Questions and Future Directions

Abstract

In this chapter, we provide an overview of cognitive neuroscience research examining the neural correlates of nonsymbolic (eg, dot arrays) and symbolic (eg, Arabic numerals) numerical magnitudes. We review how nonsymbolic and symbolic numbers are represented in the parietal cortex of the human brain across development. We then discuss whether number is represented abstractly or if representations in the human parietal cortex are format dependent. Subsequently, we highlight parallels between the neural underpinnings of (nonsymbolic and symbolic) numerical magnitudes and nonnumerical, continuous magnitudes such as space, time, and luminance. We conclude that number is likely processed using a general magnitude system used to process both numerical and nonnumerical magnitudes, which is instantiated in right lateralized regions of the parietal cortex. Regions in the left parietal cortex may specifically support symbolic numerical representations. Finally, we highlight the need for research to illuminate how symbols are mapped onto nonsymbolic or nonnumerical magnitude representations.