Direct access from meaning to orthography in Chinese: A case study of superior written to oral naming

Abstract

Background: For alphabetic scripts, the obligatory phonological mediation hypothesis about written language processing has been seriously challenged by case reports of acquired dyslexia and dysgraphia. Evidence against the hypothesis mainly comes from superior performance on written production over oral production of the same lexical items. In Chinese, the absence of grapheme-to-phoneme conversion, the presence of a character component providing a semantic cue to the meaning of many phonetic compound characters, and the great extent of homophony have led to the view that the orthography is meaning based rather than speech based. However, psycholinguistic studies of character recognition have obtained conflicting results regarding the relative time course of activation of phonological vs semantic information. Aims: This paper addresses the phonological mediation hypothesis through describing the performance pattern of a Cantonese-speaking brain-injured individual, LKY, on tasks involving oral and written production of single Chinese words. Methods and Procedures: The range of tasks administered to LKY included visual-spatial analysis, auditory discrimination, written and spoken lexical decision, repetition, oral and written picture naming, reading aloud and writing-to-dictation of object names, homophone identification and judgements, and verbal and non-verbal semantic tests. Outcomes and Results: LKY performed normally on tasks assessing the processing of visual, auditory, orthographic, and verbal input. He was moderately impaired in repeating words and phrases. His performance on the two naming tasks, reading aloud, and writing-to-dictation was clearly disrupted. In addition, he was unable to retrieve phonological information from orthographic input, given his poor ability to make homophone judgements and identification. While he could select objects that are functionally related in non-verbal semantic tests, he was impaired in accessing meaning from verbal materials. The most significant features of his performance pattern were his superior written over oral picture naming and better written naming than writing-to-dictation of the same stimuli. Conclusions: The discrepancies in performance between oral and written naming and between the written tasks with pictorial vs oral input were due to deficits at the phonological level. Such dissociations support the view that written production of Chinese, similar to the situation with alphabetic writing systems, is not parasitic on phonology, and thereby disconfirm the obligatory phonological mediation hypothesis. © 2006 Psychology Press Ltd.