Distinct representations of symbolic ordinality and quantity: evidence from neuropsychological investigations in a Chinese patient with Gerstmann's syndrome

Abstract

A number of recent studies have shown conflicting evidence as to common or distinct representations between symbolic ordinality and quantity. We investigated this issue through a series of neuropsychological tests in a unique Chinese patient with the left angular gyrus and left supramarginal gyrus lesions. Behavioral experiments revealed that (1) the patient showed Gerstmann syndrome, with minimal anomia and alexia and (2) the patient showed the dissociation among number semantic representations with relatively preserved symbolic quantity knowledge and impaired processing of symbolic order meaning. Together with existing evidence in the literature, results of the current study suggest that there might be two separate cognitive representations of symbolic ordinality and quantity in logographic language according to this dissociation. Most importantly, another merit of this study is that the left angular gyrus and left supramarginal gyrus might be necessary to symbolic ordinality representation.

Keywords: Gerstmann syndrome; Neuropsychological test; Ordinality; Quantity.