关键词: 词素转置效应, 词素位置概率, 词汇位置编码, 双字词识别

Abstract:

Letter/character position information plays an important role in visual word identification. In alphabetic and Chinese reading, a bulk of studies using the lexical decision paradigm have shown that a transposed letter/character (TL/TC) nonword prime, created by transposing two adjacent letters/characters of a word, activates the representation of its base word to a greater degree than a substituted letter/character (SL/SC) nonword prime, in which two corresponding letters/characters, or even one letter/character are replaced. This phenomenon is called the Transposed Letter / Character effect, indicating that the letter/character position encoding is not strict during word identification. In alphabetic languages (like English, German and Spanish), letter order encoding mechanism have been included in the models of word recognition in different ways. Chinese is a logographic language, with quite different characteristics from alphabetic languages, so the letter position encoding models developed from alphabetic languages might not be fully applied to Chinese. In the present study, we conducted two parallel experiments to examine whether and how character positional probabilities influenced the degree of flexibility of position encoding in two-character word identification. We utilized a masked priming paradigm lexical judgment task and manipulated the priming type (original word priming, transposed word priming, substitution priming) and priming times (80 ms, 150 ms, 300 ms).

In Experiment 1, we examined how word’s initial character's positional probability influenced the degree of flexibility of position coding in two-character word identification. The initial character’s positional probability of two-character target words was manipulated as being either high or low, and the final character was kept identical across the two conditions. In Experiment 2, an analogous manipulation was made for the final character of the target word to check whether the final character's positional probability of two-character words influenced the degree of flexibility of position coding in two-character word identification.

We found that the positional probability of both the initial and final character of a word influences Chinese two-character word identification. To be somewhat different, the positional probability of final character was processed throughout the whole lexical identification (from 80 ms to 300 ms), whereas the positional probability of initial character was processed only in the middle stage of lexical identification (around 150 ms). This finding suggests that the final character's positional probability is more important than that of initial character’s during Chinese two-character word identification. Furthermore, the positional probability of the initial character rather than the final character modulated the degree of flexibility of position coding in two-character word identification, such that the more frequently a character being used as word beginning, the more flexible of position coding.

Based on these findings, we argue that the role of positional probability of initial and final character might be somewhat different during Chinese word identification: the positional probability of initial character may be related to positional information processing, whilst the positional probability associated with the final character might be more related to identity information processing in word identification.

Key words: transposed-character effect, character positional probability, character position encoding, two-character word identification