Handelsman & Dotan 2013 number reading supplementary

Dysnumeria, a learning disorder that disrupts number reading and writing, hinders numerical literacy and thus disturbs everyday life. However, little is known about its prevalence or its origins. Here, we provide data on the number-reading performance of typical readers (n=143) and readers with dysnumeria (n=50), who read aloud 120 multi-digit numbers. The typical readers made 6.4% errors on average, and 6.2% of them turned out to have dysnumeria – similar to the reported prevalence of dyslexia and dyscalculia. We also analyzed the types of errors, as specific error types can be traced back to specific number-reading processes. Both typical readers and those with dysnumeria exhibited a high rate of syntactic errors, indicating that the main challenge in reading numbers is the need to handle the number’s syntactic structure.