title: Breaking down number syntax: spared comprehension of multi-digit numbers in a patient with impaired digit-to-word conversion.
abstract: Can the meaning of two-digit Arabic numbers be accessed independently of their verbal-phonological representations? To answer this question we explored the number processing of ZN, an aphasic patient with a syntactic deficit in digit-to-verbal transcoding, who could hardly read aloud two-digit numbers, but could read them as single digits ("four, two"). Neuropsychological examination showed that ZN's deficit was neither in the digit input nor in the phonological output processes, as he could copy and repeat two-digit numbers. His deficit thus lied in a central process that converts digits to abstract number words and sends this information to phonological retrieval processes. Crucially, in spite of this deficit in number transcoding, ZN's two-digit comprehension was spared in several ways: (1) he could calculate two-digit additions; (2) he showed good performance in a two-digit comparison task, and a continuous distance effect; and (3) his performance in a task of mapping numbers to positions on an unmarked number line showed a logarithmic (nonlinear) factor, indicating that he represented two-digit Arabic numbers as holistic two-digit quantities. Thus, at least these aspects of number comprehension can be performed without converting the two-digit number from digits to verbal representation.
authors.affiliation: Language and Brain Lab, School of Education and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel; INSERM, U992, Cognitive Neuroimaging Unit, F-91191 Gif/Yvette, France. Electronic address: dror.dotan@gmail.com.
authors.forename: Dror
authors.initials: D
authors.lastname: Dotan
authors.affiliation: Language and Brain Lab, School of Education and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv 69978, Israel.
authors.forename: Naama
authors.initials: N
authors.lastname: Friedmann
authors.affiliation: INSERM, U992, Cognitive Neuroimaging Unit, F-91191 Gif/Yvette, France; Collège de France, F-75005 Paris, France; CEA, DSV/I2BM, NeuroSpin Center, F-91191 Gif/Yvette, France; University Paris-Sud, Cognitive Neuroimaging Unit, F-91191 Gif/Yvette, France.
authors.forename: Stanislas
authors.initials: S
authors.lastname: Dehaene
mesh_terms: D000368:Aged; D000381:Agraphia / Q000209:etiology / Q000503:physiopathology* / Q000534:rehabilitation; D001037:Aphasia / Q000209:etiology / Q000503:physiopathology* / Q000534:rehabilitation; D001072:Apraxias / Q000209:etiology / Q000503:physiopathology* / Q000534:rehabilitation; D032882:Comprehension / Q000502:physiology*; D006801:Humans; D007802:Language; D008297:Male; D008433:Mathematics; D009483:Neuropsychological Tests; D020521:Stroke / Q000150:complications* / Q000503:physiopathology; D000071939:Stroke Rehabilitation
keywords: Arithmetic; Holistic processing; Number representation; Number syntax; Two-digit numbers