自然阅读中儿童和成人新词学习能力的差异比较:基于眼动的证据

Observing Eye Movement to Measure Vocabulary Retention Capability between Children and Adults during Reading

从读者重复学习新词时眼动行为经历的变化,揭示儿童和成人自然阅读中新词学习能力的差异。构造双字假词作为新词,将其嵌在五个语境中,记录儿童和成人阅读时的眼动轨迹。结果发现:随着新词学习次数的递增,儿童和成人在新词上的首次注视时间呈相同变化;在对新词的凝视时间和再注视概率上,成人在第二次阅读时就大幅下降,而小学生在第四次阅读时才开始下降。表明成人新词学习能力高于儿童体现在词汇加工的相对晚期阶段。

Children learn about 3000 vocabulary words per year during the primary school period, and about 30% of the vocabulary is acquired from the natural reading. That is, with the increased exposure of novel words to different sentential contexts, readers have gradually formed the novel lexical representation in their mental lexicon. Previous studies have shown that adults could form a more consolidated lexical representation than children during the initial four encounters with different contexts based on their eye movement behaviors. In the present study, we endeavor to explore how a reader＇s eye movement behavior changes during the initial several encounters when learning the novel words in the natural reading. Specifically, we focus on the issue of whether the change of reader＇s eye movements show the developmental trends with the increasing number of encounters with different contexts. We adopted a group of high-frequency characters to construct 30 two-character pseudowords as novel words. Every target word was embedded into five sentence frames, each of which provided a context describing a plausible meaning of the pseudoword it contained. Each pseudoword was assigned to one of ten real-world semantic categories. In order to test whether or not readers had learned the semantic category of each pseudoword after reading it within five sentential contexts, a multiple choice semantic category question （presenting ten categories, of which five were used in the experiment and five were distractors） was presented to the participants. The eye movements of two groups of participants （including adults and 9-year olds） were recorded when they read the sentences. The first aspect of results showed that children and adults undergo the same pattern of change on first fixation duration with the increasing reading of novel words through sentential contexts. It suggests that there is no developmental trend between children and adults in the very early stage of lexical processing when learning the novel words through context. More results showed that gaze duration and total reading time was much shorter among adults, and that there was less refixations on the novel words when they read a second time. In contrast, children saved some gaze duration and refixations probability on the novel words in the fourth time of reading novel words within contexts, but it did not occur among children during the first three times of reading. These results indicate that adults showed better performance than children in the later stage of lexical processing when learning novel words through contexts.