Visual perception of Chinese orthography: from characters to sentences

There are different aims in this thesis. The primary aim is to investigate visual perception in Chinese orthography, from its fundamentally distinct unit, characters, to sentence reading. The first aim of the thesis is to investigate how a single Chinese character is processed in many ways. We have looked into an effect called orthographic satiation/decomposition (Cheng & Wu, 1994). It refers to the feeling of uncertainty about the composition of some characters when staring at a character for too long. Lee (2007) extended Cheng and Wu’s study (1996), and the results have showed that orthographic satiation occurred faster in females than males. We replicated Lee’s study (Experiment 1) (Chapter 3), and have found that: (1) there was no significant difference between male and female and (2) a radical that can stand alone as a single character makes characters in which it occurs resistant to satiation. Following orthographic satiation, in Chapter 4, we explored the preference for eye/hemisphere visual pathways in Chinese characters (Experiment 2 & 3) and words (Experiment 4). In English, researchers have reported a contralateral preference when four-letter words were presented very quickly using a haploscope (Obreg´on & Shillcock, 2012) . It raises the question of whether presenting Chinese characters and words will show similar results considering the complexity and the special characteristics of Chinese orthography. We presented Chinese characters and words to participants using a haploscope. Our results showed that: (1) the contralateral visual pathway was preferred in perceiving right-left structured Chinese characters and two-character words, (2) when a semantic radical is projected to the LH, participants are able to recognise the semantic component better, (3) neighbourhood size (NS) (Tsai, Lee, Lin, Tzeng & Hung, 2006) affects how participants recognise words, and(4) males do better than females recognising characters but not words. After investigating the recognition of Chinese characters and words, we analysed the eye-movements in Chinese and English reading corpora. The processes of reading are intuitively thought to be more complex than perceiving a single character or words. The last studies in the thesis focused on the reading behaviours in Chinese and English. The eye movement differences and similarities between reading Chinese and English were investigated. In Chapter 5, we showed that reading Chinese elicits more divergence of the eyes within a fixation, compared with reading English. We interpreted these data in terms of recent demonstrations that apparent size causes increases in visual sensitivity (Arnold & Schindel, 2010) and engages more cortical resource in V1 (Kersten & Murray, 2010). Our analyses were based on movement within exactly temporally synchronized binocular fixations in the reading of Chinese and English 5000-word multi-line texts, using monocular calibration, with EyeLink-2 technology. When faced with visually complex orthography, the oculomotor system ‘tricks’ the rest of the visual system into ‘zooming in’ on the text. We consolidated the relevant theorizing into the ‘Divergence Affects Reading’ (DOLLAR) Theory. In Chapter 6, we reported that (1) vertical movements within a fixation tend to be smaller than horizontal ones, and (2) vertical movements within a fixation tend to be upwards. We speculated that it is appropriate for the earlier part of the fixation to be associated with visual recognition and for the later part of the fixation to be associated with executive action. The tendency to move upwards also suggested that in real-world reading, the upper part of words/characters were informative. In the last chapter analysing the reading corpus (Chapter 7), we reported corrective saccades after return sweeps. We found that in English, there were more corrective saccades after return sweeps than in Chinese. We interpreted these data in terms of spatial coding (Kennedy & Murray, 1987). In terms of Chinese and English differences, the stimuli that were used in our corpus show that the length for each line was different in English. The length for each line in Chinese was less different. Though the first character of each line was at the same place for two languages, it was more difficult for English subjects to locate the correct place after return sweeps because the length of return sweeps was different. In short, this thesis investigated visual perception in Chinese orthography, in terms of characters, words, and real-world reading. Moreover, we compared the differences and similarities between languages (English and Chinese). Despite the fact that the orthographies of English and Chinese are very different, we still found similar effects (e.g., contralateral preference) between them. This thesis thus has contributed to a better understanding of the differences and similarities between English and Chinese in terms of the orthographies