大小字号的文本对中文读者眼动模式和阅读知觉广度的影响

摘 要 研究以眼动仪为工具，采用移动窗口范式考察不同字号文本对读者阅读知觉广度和眼动模式的影响。实验结果发现，被试阅读大、小字号文本时的阅读知觉广度都是四个字。字号大小不影响读者的阅读知觉广度，但是影响读者的眼动模式。具体表现为：被试阅读小号字文本的平均注视时间、总注视时间比大号字文本长，平均眼跳距离更短，相对眼跳距离（单位为字的个数）更长，注视次数更多。

The Eye Movements and Perceptual Span of Different Font Size Text in Chinese Reading

Abstract The perceptual span is the area of effective vision from which useful information can be obtained during a fixation in reading. Previous studies had proved that the perceptual span will be influenced a function of reading skill, the age of readers, the different working memory capacity and the difficulty of different Chinese materials. However, little was known about the perceptual span and eye movements of different font size text in Chinese reading. Here we reported a study that font size text modulated the amount of information acquired during a fixation in Chinese reading. The experiment design was 2 (font size: 18 and 36 font size conditions) × 6 (display conditions: two characters, three characters, four characters, five characters, six characters and whole line condition)mixed design. The moving window paradigm was adopted. Twenty-four native Chinese readers read 120 sentences under twelve experimental conditions with their eye movements being monitored. Eye movements were recorded by a SR Research Eyelink Ⅱ(sample rate =120 Hz). The stimulus was presented in black on a white background. Participants were seated 70 cm away from the monitor. The whole experiment lasted about 25-30 minutes. The results showed that the perceptual span of 16 and 32 font size conditions was four characters. Compared with the circumstance of the bigger font text (32 font size conditions), there were more fixations, shorter mean fixation duration and total fixation duration, longer mean saccade amplitude(the numbers of character as the unit) but lower mean saccade amplitude under the circumstance of smaller font text (16 font size conditions) . So the tentative conclusion was that the size of perceptual span of the bigger font text was the same as that of the smaller font text, but the eye movement pattern was different. Key words perceptual span, font size, eye movements, Chinese reading