Representations of grapho-motor patterns unique to Chinese character writing: evidence from a patient with mirror writing.

This study investigated the grapho-motor patterns used in writing Chinese characters. A Chinese patient, CSC, who demonstrated post-brain-injury mirror writing, was recruited. In Experiment 1, non-mirrored writing responses were obtained when CSC was instructed to copy asymmetrical non-verbal symbols and pictures. Resembling the patterns observed in a patient's writing reported in a previous study, it was hypothesized that CSC's mirror writing was a result of untransformed preserved grapho-motor patterns. In Experiments 2 and 3, CSC was further instructed to copy real Chinese characters, pseudo-characters with authentic radicals and logographemes (i.e., stroke clusters that frequently occur in radicals), and Hangul characters with stroke clusters resembling the shapes of authentic logographemes. The results showed that CSC demonstrated mirror writing only when authentic Chinese orthographic units were involved. Non-mirrored writing responses were obtained from stimuli without authentic Chinese orthographic units. In sum, CSC's performance supported the existence of grapho-motor patterns of Chinese orthographic units represented in the brain. Theoretical implications were discussed.