Effects of word frequency and visual complexity on eye movements of young and older Chinese readers

Research using alphabetic languages shows that, compared to young adults, older adults employ a risky reading strategy in which they are more likely to guess word identities and skip words to compensate for their slower processing of text. However, little is known about how ageing affects reading behaviour for naturally unspaced, logographic languages like Chinese. Accordingly, to assess the generality of age-related changes in reading strategy across different writing systems we undertook an eye movement investigation of adult age differences in Chinese reading. Participants read sentences containing a target word (a single Chinese character) that had a high or low frequency of usage and was constructed from either few or many character strokes, and so either visually simple or complex. Frequency and complexity produced similar patterns of influence for both age groups on skipping rates and fixation times for target words. Both groups therefore demonstrated sensitivity to these manipulations. But compared to the young adults, the older adults made more and longer fixations and more forward and backward eye movements overall. They also fixated the target words for longer, especially when these were visually complex. Crucially, the older adults skipped words less and made shorter progressive saccades. Therefore, in contrast with findings for alphabetic languages, older Chinese readers appear to use a careful reading strategy according to which they move their eyes cautiously along lines of text and skip words infrequently. We propose they use this more careful reading strategy to compensate for increased difficulty processing word boundaries in Chinese.     

词频、可预测性及合理性对目标词首次注视位置的影响

采用三项实验分别考察了目标词的词频、可预测性和合理性对读者眼动模式的影响。结果显示:(1)词频、可预测性和合理性对目标词语的凝视时间和总注视时间都有显著影响,但在首次注视时间上主效应不显著;(2)词频和可预测性不影响目标词的跳读率和再注视概率,而合理性对目标词的再注视概率产生显著的影响;(3)远注视点眼跳倾向于将首次注视位置着落于目标词的开端部位,而近注视点眼跳倾向于将首次注视着落于目标词的中央部位;词频、可预测性和合理性均不影响首次注视位置。     

汉语老年读者的多词单元加工：来自眼动研究的证据

选取由两个双字词组成的多词组合（单词组合、模糊词组合、双词组合）,比较老年人和青年人对多词单元的加工情况。结果发现,相比于其他两类组合,所有被试在单词组合上的注视时间更短,第一遍注视次数更少,成分词上的注视时间更短,跳读率更高,表现出多词单元的加工优势,而且这一加工优势不存在显著的年龄差异。结果表明,汉语老年读者同样将多词单元作为整体进行加工。     

Information influences the pattern of eye fixations during sentence comprehension

How does the pattern of eye fixation vary as an informative part of a word is encountered? If the processing of information lags behind the movement of the eyes, then we should expect no variation in the pattern; but if processing is immediate, then the movements of the reader's eyes should correspond to the distribution of information being inspected. An experiment is reported which examined the ways that the text ahead of the point of current fixation can be used to guide the eyes to future fixations, by monitoring fixations during a sentence comprehension task. The patterns of eye fixations upon words with uneven distributions of information (where, for example, words predictable from the sight of their first few letters but not from their last few letters are defined as containing informative beginnings) were observed, and it was found that more and longer fixations were produced when subjects looked at the informative parts of words, particularly at the informative endings of words. The results support the suggestion that eye movements are under the moment-to-moment control of cognitive mechanisms.     

A dual-route perspective on eye movements of dyslexic readers

This study assessed eye movement abnormalities of adolescent dyslexic readers and interpreted the findings by linking the dual-route model of single word reading with the E-Z Reader model of eye movement control during silent sentence reading. A dysfunction of the lexical route was assumed to account for a reduced number of words which received only a single fixation or which were skipped and for the increased number of words with multiple fixations and a marked effect of word length on gaze duration. This pattern was interpreted as a frequent failure of orthographic whole-word recognition (based on orthographic lexicon entries) and on reliance on serial sublexical processing instead. Inefficiency of the lexical route was inferred from prolonged gaze durations for singly fixated words. These findings were related to the E-Z Reader model of eye movement control. Slow activation of word phonology accounted for the low skipping rate of dyslexic readers. Frequent reliance on sublexical decoding was inferred from a tendency to fixate word beginnings and from short forward saccades. Overall, the linkage of the dual-route model of single word reading and a model of eye movement control led to a useful framework for understanding eye movement abnormalities of dyslexic readers.     

Eye fixations are influenced by the distribution of information within words

Reader's eye movements were monitored while they inspected isolated words in preparation for a synonym judgement task. The 10-letter words appeared on a screen near the point of fixation, with the first fixation being imposed near the beginning, or the centre, or the ending of the word. The words themselves had uneven distributions of information, in that the beginnings or the endings contained common sequences of letters in English. Three types of words were used: those with very redundant endings (e.g., yearningly), with moderately redundant endings (e.g., varnishing), and with moderately redundant beginnings (e.g., contravene). Redundancy was defined in terms of the total number of words in English which possess that particular sequence of five letters as the beginning or the ending. The experiments asked whether the convenient viewing location within a word varied according to the distribution of information, and whether the extent of redundancy in a word ending is reflected in the distribution of visual attention given to the word. The results were analysed separately for those cases where the reader made just two fixations upon the word before moving to the synonym task, and for those cases where the reader made exactly three fixations. These were the dominant fixation patterns. Evidence for the notion of a convenient viewing position consisted of long first fixations (when there were just two fixations), when this fixation was near the centre of the word. The distribution of information within the words did not influence the duration of the first fixation, although the duration of the gaze within each half-word did increase when more informative letter sequences were being inspected. The extent of redundancy was also seen to influence the inspection patterns, when a comparison was made between the two types of words with redundant endings. Words with very redundant endings received fewer fixations when the first fixation was at the beginning, and for words gaining exactly two fixations, the second fixation was shorter if the word had a very redundant ending.     

汉语阅读过程中词切分的位置：一项基于眼动随动显示技术的研究

采用眼动随动显示技术, 通过分析动态协助或干扰词切分对阅读过程的影响, 考察汉语阅读过程中词切分的位置与数量。包括两项实验：实验一通过改变注视点附近词语的颜色来促进词汇的加工进程, 发现协助词n+1切分可改变被试的眼动模式, 说明至少加工词n+1可导致词切分效果; 实验二以类似方法干扰相应的词汇加工进程, 发现在某些实验条件下被试的眼动模式朝相反方向变化, 表明实验一结果并非由外源注意转移引起。综合分析两个实验中各种条件下首次注视概率分布、再注视时的首次注视时间和单一注视时间的差异, 得出以下结论：在汉语阅读中存在两种词切分现象, 一种由加工词n+1引起, 另一种由加工词n引起。     

Immediate and delayed effects of word frequency and word length on eye movements in reading: a reversed delayed effect of word length

Three experiments examined the effects in sentence reading of varying the frequency and length of an adjective on (a) fixations on the adjective and (b) fixations on the following noun. The gaze duration on the adjective was longer for low frequency than for high frequency adjectives and longer for long adjectives than for short adjectives. This contrasted with the spillover effects: Gaze durations on the noun were longer when adjectives were low frequency but were actually shorter when the adjectives were long. The latter effect, which seems anomalous, can be explained by three mechanisms: (a) Fixations on the noun are less optimal after short adjectives because of less optimal targeting; (b) shorter adjectives are more difficult to process because they have more neighbors; and (c) prior fixations before skips are less advantageous places to extract parafoveal information. The viability of these hypotheses as explanations of this reverse length effect on the noun was examined in simulations using an updated version of the E-Z Reader model (A. Pollatsek, K. Reichle, & E. D. Rayner, 2006c; E. D. Reichle, A. Pollatsek, D. L. Fisher, & K. Rayner, 1998).     

Perceptual salience of derivational suffixes in visual word recognition

This study analyzes the role of derivational suffixes in visual word recognition, tracking the eye movements of 31 participants in a sentence-reading task in Spanish. Perceptual salience of suffixes was operationalized as the proportion of letters represented by the suffixes with respect to the full words, that is, we relate the number of letters comprising the suffixes to the number of letters in the words in which they appear. The results reveal a significant role in first fixation duration of both word frequency – the more frequent the word, the shorter the fixations, and perceptual salience – the more salient the suffix, the longer the fixations. Moreover, in gaze duration, our results show a main effect of word length – the longer the word, the longer the fixations; word frequency; and significant interactions between word frequency and perceptual salience of suffixes on the one hand – the effect of word frequency is only significant when perceptual salience of suffixes is high, and between word frequency and word length on the other hand – the frequency effect decreases as word length increases. Overall results are interpreted in the light of the dual route models by which full-form and morphological processing interactively cooperate in visual word recognition.     

Reading strategy modulates parafoveal-on-foveal effects in sentence reading

Task demands and individual differences have been linked reliably to word skipping during reading. Such differences in fixation probability may imply a selection effect for multivariate analyses of eye-movement corpora if selection effects correlate with word properties of skipped words. For example, with fewer fixations on short and highly frequent words the power to detect parafoveal-on-foveal effects is reduced. We demonstrate that increasing the fixation probability on function words with a manipulation of the expected difficulty and frequency of questions reduces an age difference in skipping probability (i.e., old adults become comparable to young adults) and helps to uncover significant parafoveal-on-foveal effects in this group of old adults. We discuss implications for the comparison of results of eye-movement research based on multivariate analysis of corpus data with those from display-contingent manipulations of target words.     

Prosodic knowledge affects the recognition of newly acquired words

An eye-tracking study examined the involvement of prosodic knowledge--specifically, the knowledge that monosyllabic words tend to have longer durations than the first syllables of polysyllabic words--in the recognition of newly learned words. Participants learned new spoken words (by associating them to novel shapes): bisyllables and onset-embedded monosyllabic competitors (e.g., baptoe and bap). In the learning phase, the duration of the ambiguous sequence (e.g., bap) was held constant. In the test phase, its duration was longer than, shorter than, or equal to its learning-phase duration. Listeners' fixations indicated that short syllables tended to be interpreted as the first syllables of the bisyllables, whereas long syllables generated more monosyllabic-word interpretations. Recognition of newly acquired words is influenced by prior prosodic knowledge and is therefore not determined solely on the basis of stored episodes of those words.     

THE EFFECT OF MEANING FREQUENCY ON PROCESSING LEXICALLY AMBIGUOUS WORDS: Evidence From Eye Fixations

Abstract —Subjects read sentences containing lexically ambiguous words while their eye movements were monitored Biased ambiguous words (those that have one highly dominant sense) were used m sentences containing a prior context that instantiated their subordinate sense Control words were matched m frequency both to the dominant and to the subordinate meaning of the ambiguous word (high- and low-frequency controls) Subjects fixated longer on both the ambiguous word and the low-frequence control than on the high-frequency control When the target was ambiguous, however, the duration of posttarget fixations was longer and the likelihood of making a regression to the target was greater than when the target was an unambiguous control The results are discussed m relation to current models of lexical ambiguity resolution     

The word grouping hypothesis and eye movements during reading

The distribution of landing positions and durations of first fixations in a region containing a noun preceded by either an article (e.g., the soldiers) or a high-frequency 3-letter word (e.g., all soldiers) were compared. Although there were fewer first fixations on the blank space between the high-frequency 3-letter word and the noun than on the surrounding letters (and the fixations on the blank space were shorter), this pattern did not occur when the noun was preceded by an article. R. Radach (1996) inferred from a similar experiment that did not manipulate the type of short word that 2 words could be processed as a perceptual unit during reading when the first word is a short word. As this different pattern of fixations is restricted to article-noun pairs, it indicates that word grouping does not occur purely on the basis of word length during reading; moreover, as the authors demonstrate, one can explain the observed patterns in both conditions more parsimoniously without adopting a word-grouping mechanism in eye movement control during reading.     

Effects of contextual constraint on eye movements in reading: A further examination

The effect of contextual constraint on eye movements in reading was examined by asking subjects to read sentences that contained a target word that varied in contextual constraint; high-, medium-, or low-constraint target words were used. Subjects fixated low-constraint target words longer than they did either high- or medium-constraint target words. In addition, they skipped high-constraint words more than they did either medium- or low-constraint target words. The results further confirm that contextual constraint has a strong influence on eye movements during reading.     

Effects of number-of-letters on eye movements during reading are independent from effects of spatial word length

Word length is an important determinant of eye movement behaviour in reading. The current study is the first attempt to disconfound a word's number of letters from its spatial extent. In a sentence-reading experiment using closely matched stimuli, clear differences were observed between target words that subtended the same visual angle but differed in number of letters: the more letters in the word, the more fixations made on the word, and the longer the duration of these fixations. Analyses of the full set of sentence words confirmed these results for a wider range of word lengths, and are consistent with a role for number-of-letters distinct from spatial extent. The most plausible explanation for these findings is that long words are subject to a reater degree of visual crowding, which is costly for both temporal and spatial eye movement systems.     

阅读过程中的词跳读及其产生的认知机制

在阅读过程中,读者并不会注视每一个词,而是不断地跳过很多词。在英文阅读中至少有30%的词被跳读,在中文阅读中近50%的字词被跳读。那么被跳读的字词是否得到加工,何时得到加工,是当前阅读过程中眼动控制模型关心的基本问题：具体包括（1）词跳读是基于副中央凹处词汇的完全识别还是部分识别后发生;（2）中央凹加工负荷是否影响对下一个词的跳读;（3）副中央凹和中央凹加工效率与词跳读的关系是什么;（4）较低水平的视觉信息（如词长、复杂性）和较高水平的语言信息（如词频、预测性）如何交互作用决定一个词的跳读。文章对上述问题进行系统分析,最后结合中文阅读中书写系统的特点,对未来中文阅读中词跳读研究进行了展望。     

Fixation positions after skipping saccades: A single space makes a large difference

During reading, saccadic eye movements are generated to shift words into the center of the visual field for lexical processing. Recently, Krügel and Engbert (Vision Research 50:1532?C1539, 2010) demonstrated that within-word fixation positions are largely shifted to the left after skipped words. However, explanations of the origin of this effect cannot be drawn from normal reading data alone. Here we show that the large effect of skipped words on the distribution of within-word fixation positions is primarily based on rather subtle differences in the low-level visual information acquired before saccades. Using arrangements of ??x?? letter strings, we reproduced the effect of skipped character strings in a highly controlled single-saccade task. Our results demonstrate that the effect of skipped words in reading is the signature of a general visuomotor phenomenon. Moreover, our findings extend beyond the scope of the widely accepted range-error model, which posits that within-word fixation positions in reading depend solely on the distances of target words. We expect that our results will provide critical boundary conditions for the development of visuomotor models of saccade planning during reading.     

Eye movements during the handwriting of words: Individually and within sentences

Handwriting, a complex motor process involves the coordination of both the upper limb and visual system. The gaze behavior that occurs during the handwriting process is an area that has been little studied. This study investigated the eye-movements of adults during writing and reading tasks. Eye and handwriting movements were recorded for six different words over three different tasks. The results compared reading and handwriting the same words, a between condition comparison and a comparison between the two handwriting tasks. Compared to reading, participants produced more fixations during handwriting tasks and the average fixation durations were longer. When reading fixations were found to be mostly around the center of word, whereas fixations when writing appear to be made for each letter in a written word and were located around the base of letters and flowed in a left to right direction. Between the two writing tasks more fixations were made when words were written individually compared to within sentences, yet fixation durations were no different. Correlation of the number of fixations made to kinematic variables revealed that horizontal size and road length held a strong correlation with the number of fixations made by participants.     

Reading long words embedded in sentences: informativeness of word halves affects eye movements

The possibility was explored that the informativeness of a specific region within a word can influence eye movements during reading. In Experiment 1, words containing identifying information either toward the beginning or toward the end were displayed asymmetrically around the point of fixation so that the reader was initially presented with either the informative or noninformative zone. Words were read with shorter summed initial fixation time when the reading was started from the informative zone. In Experiments 2 and 3, the target words were presented in sentences that were to be comprehended. More attention was given to the informative endings of words than to redundant endings. The latter were also skipped more often. The duration of the first fixation was not affected by information distribution within the word, whereas the second fixation duration was. The results of these experiments lend good support to the hypothesis of immediate lexical control over fixation behavior and to the notion of a convenient viewing position.