Abstract: The issue of the role of orthography and phonology in activating the meanings of visual words has provoked a large amount of research for alphabetic writing systems, especially for English. A great deal of research has demonstrated that phonological codes are activated early in English silent reading. For Chinese, however, the role of orthography and phonology remains controversial. Specifically, some empirical evidence supports directly access hypothesis, some supports phonologically mediated access hypothesis, and some for dual-rout hypothesis. Unlike English, the basic unit of writing in Chinese is character which does not associated with phonemes but with meaning instead. Chinese provides an interesting case for testing the current models of visual word recognition that developed essentially for alphabetic writing systems.
The current study focused the issue that how orthography and phonology is activated during Chinese silent reading when target words were presented in different constrained sentence contexts. Two experiments were conducted by manipulating the word frequency of homophone pairs and types of target words. All the target words were Chinese single character words and were matched for their stroke numbers across conditions. In addition, the homophone density (the number of homophones of a character has) was matched between the high- and low- frequency homophone pairs. Eye tracking method was used in this study and three types of eye movement measures such as first fixation duration, gaze duration, and total fixation duration were examined to determine how orthography and phonology is activated during Chinese sentence reading.
The results showed that a reversed effect of word frequency occurred for orthographical targets in the fixation duration and total fixation duration, while both gaze duration and total fixation duration were significantly shorter for the homophonic targets than unrelated controls when the targets were presented in the highly constrained sentence context. However, when the targets were presented in the lowly constrained sentence context, all the three measures of fixation duration were significantly shorter for homophonic targets than unrelated controls.
In conclusion, our data indicate that sentence context influences the activation of phonology and orthography during Chinese silent reading. It is orthography rather than phonology plays an early key role in reading highly constrained sentences, but both phonology and orthography are important in the late stage of processing. In contrast, for the low constraint sentence, both phonology and orthography play an important role at the early stage of processing. These findings suggest that the meaning of word can be accessed directly by orthography or dual routs by orthography and phonology during Chinese sentence reading.

Key words: sentence context, Chinese reading, orthography, phonology, eye movements