Numbers in the Dark

Abstract

Abstract How do we represent numbers in the dark? Is vision necessary in the elaboration of numerical representations and skills? These questions are of great interest, as for a long time, the role of vision has been implicitly and explicitly stressed in the acquisition and development of numerical representations and skills. Over the last few years, several researchers have directly addressed this question by studying the impact of early visual deprivation on numerical representations and skills. Different numerical processes have been investigated in blind people: numerical comparison, parity judgement, numerical bisection, numerical estimation, subitizing, and finger-counting. All these different studies, reviewed in the current chapter, strongly demonstrate that vision is not necessary in the elaboration of numerical representations and skills. However, more surprisingly, early visual deprivation might have a positive impact on numerical skills.