Abstract:

The Transposed-Letter effect (TL effect) demonstrates the importance of letter position encoding in word recognition, highlighting its stable flexibility. In order to understand the processing mechanisms of word recognition, recent research investigated letter position encoding in words with different morphological structures. If the compound word is processed in the morphological decomposition manner, the transposition across morphemes will cause more interference than within morphemes. Resulting in a reduced TL effect. In Chinese, it was also found that the character position encoding is flexible, which is demonstrated by the Transposed-Character (TC) effect. It was examined whether the character position encoding is different between the monomorphemic word and the compound word. And no significant difference was found between them. It indicates that the compound word is accessed in a holistic route. However, the Chinese compound word consists of various types of morphological structures. Since the semantic role of each morpheme is different across morphological structures, the subordinative compound word, which is formed by a modifier and a semantic headedness, might have more rigid character position encoding than the coordinative compound word, which is formed by two semantic headednesses. Then causes different processing mechanisms. Therefore, this study employed eye-tracking technology and the boundary paradigm to explore character position encoding in different morphological structures of two-character words.
Seventy-eight students participated in the experiment, which utilized a 3 (Word type: monomorphemic word, subordinate compound, coordinative compound) × 3 (Preview type: identical preview, transposed preview, unrelated preview) within-participants design. We hypothesized the TC effect exists in all types of the two-character word. However, for the processing of the subordinative compound word, the assignment of the semantic role is needed. Thus, the character flexibility of the subordinative compound word should be lower than that of the coordinative compound and monomorphemic word, which is indicated by the lower TC effect for the subordinative compound word.
The results showed that the fixation times (First fixation, Gaze duration, and Regression path reading time) of transposed previews were significantly shorter than those of unrelated previews. It indicates a significant TC effect and demonstrates the flexibility of character position encoding. Furthermore, the fixation time of identical previews was significantly shorter than that of transposed previews. It indicates that character position encoding is important in accurate word recognition. We also found an interaction effect between word type and preview type. The subordinate compound word exhibited a smaller TC effect than the coordinative compound word and the monomorphemic word. However, the TC effect of the coordinative compound word did not differ from that of the monomorphemic word. Additionally, the difference between the identical preview and the transposed preview conditions was greater for the subordinate compound word than for the coordinative compound word and the monomorphemic word. However, the difference between identical preview and transposed preview conditions of the coordinative compound word did not differ from that of the monomorphemic word. The means and standard deviations are shown in Table 1, and the results of the linear mixed effects models are shown in Table 2.
In conclusion, the character position encoding of the monomorphemic word and the coordinative compound word showed greater flexibility than that of the subordinate compound word. At the same time, no significant difference was observed between the monomorphemic word and the coordinative compound word. These findings suggest that the morphological structure of the two-character word directly influences the TC effect, supporting the dual-route race model of the processing of the morphological complex word and providing empirical support for the Chinese reading model.

Key words: compound words, transposed-character effect, position encoding, morphological structure