ABSTRACT
Objective To determine whether attention allocation deficits contribute to nonfluent aphasia during orthography, phonology, and semantic processing with Chinese characters. Methods Sixteen patients and sixteen controls participated in single and dual tasks. In the single task participants were required to read Chinese characters silently and to make radical, semantic, and final sound judgments (for example, whether the charactersincluded the sound 'ang' ) simultaneously. During the dual task the only difference was that the participants wereasked to read the presented characters aloud and make the same three judgments. Reaction time and error rate were recorded and analysed. Results Reaction times in orthographic judgment were significantly longer for patients than for controls in both task setups. The error rate was also significantly higher. The patients' reaction times in makingphonological judgments in the dual task were significantly longer than in the single task, but there was no significantdifference in error rates between the patients and the controls. In making semantic judgments, neither reaction times nor error rates differed significantly with either the single or dual task protocol. Conclusion Attention allocation deficits play a key role in Chinese character orthographic and phonological processing for nonfluent aphasia sufferers.