场景知觉中的眼动分析指标:基于注视和眼跳视角

眼动范式是场景知觉研究的重要方法之一,可以通过对场景知觉过程中眼动变化的实时记录,真实地反映场景信息加工的内在心理机制;然而,人们的心理活动是极其复杂的,与之相应的眼动指标也具有多样性和复杂性。对眼动指标的分析,有不同的分析维度,比如整体和局部、时间和空间等。本文回顾了已有的眼动指标分类,并尝试从注视和眼跳的视角对场景知觉过程中的眼动指标进行分类。在此基础上,从界定标准、心理学意义、研究应用等方面对相应的眼动指标进行分析和介绍,最后提出了眼动指标分析和应用可能存在的问题,以及未来研究可能拓展的领域。     

Reading Text Under Normal and Disappearing Presentation Conditions

InthispaperIwillsummariseaseriesofex鄄perimentsinwhichwe[1,2]investigatedwhetheritwaspossibletoinducea"gapeffect"duringreadingandtoexaminehowwellpeoplecanreadwhenthetextliterallydisappearsfrominfrontoftheireyes.Tocarryouttheworkwerecordedreaders'eyemovementsandemployedanovelsac鄄cadecontingentchangetechniqueinwhichwemadethewordthatthereaderwasfixatingdisap鄄pear60msafterfixationonset.Inadditiontoin鄄vestigatingwhetheragapeffectmightoccurduringreading,thisworkalsoinvestigatedwhethertheprimaryde…     

消失文本条件下认知控制的眼动研究

通过考察消失文本条件下的词频效应来探讨影响中文阅读眼动模式的控制因素。实验1发现当读者所注视的双字词在80ms后消失不会影响其正常阅读。实验2在实验1的基础上将材料的呈现时间设置为80ms,结果发现不论是正常阅读还是消失文本条件下均出现了显著的词频效应,结果支持眼动的认知控制模型。     

中文阅读中副中央凹区域文本信息加工时程的眼动研究

副中央凹文本对阅读有非常重要的作用,考察读者在注视何时起对其加工有助于解决阅读中词汇加工方式的理论问题,当前研究结果存在很大争论。本研究采用消失文本范式,操纵词n-1和n+1的呈现时间(0m/40ms),考察读者加工两侧副中央凹信息的时程。结果发现,相比0ms,在注视早期40ms内,词n+1的呈现能够显著促进阅读加工,而词n-1未对阅读产生影响,表明右侧副中央凹信息的加工发生在注视早期,而左侧则未发生在该早期阶段。结果支持阅读眼动控制的并列加工模型。     

True three-dimensional displays that allow viewers to dynamically shift accommodation, bringing objects displayed at different viewing distances into and out of focus.

Under natural viewing conditions, viewers do not just passively perceive. Instead, they dynamically scan the visual scene by shifting their eye fixation and focus between objects at different viewing distances. In doing so, the oculomotor processes of accommodation (eye focus) and vergence (angle between lines of sight of two eyes) must be shifted synchronously to place new objects in sharp focus in the center of each retina. Accordingly, nature has reflexively linked accommodation and vergence, such that a change in one process automatically drives a matching change in the other. Conventional stereoscopic displays force viewers to try to decouple these processes, because while they must dynamically vary vergence angle to view objects at different stereoscopic distances, they must keep accommodation at a fixed distance--or else the entire display will slip out of focus. This decoupling generates eye fatigue and compromises image quality when viewing such displays. In an effort to solve this accommodation/vergence mismatch problem, we have built various prototype displays that can vary the focus of objects at different distances in a displayed scene to match vergence and stereoscopic retinal disparity demands and better simulate natural viewing conditions. By adjusting the focus of individual objects in a scene to match their stereoscopic retinal disparity, the cues to ocular accommodation and vergence are brought into agreement. As in natural vision, the viewer brings different objects into focus by shifting accommodation. As the mismatch between accommodation and vergence is decreased, natural viewing conditions are better simulated and eye fatigue should decrease.     

Word frequency in fast priming: Evidence for immediate cognitive control of eye movements during reading

Numerous studies have demonstrated effects of word frequency on eye movements during reading, but the precise timing of this influence has remained unclear. The fast priming paradigm was previously used to study influences of related versus unrelated primes on the target word. Here, we use this procedure to investigate whether the frequency of the prime word has a direct influence on eye movements during reading when the prime–target relation is not manipulated. We found that with average prime intervals of 32 ms readers made longer single fixation durations on the target word in the low than in the high frequency prime condition. Distributional analyses demonstrated that the effect of prime frequency on single fixation durations occurred very early, supporting theories of immediate cognitive control of eye movements. Finding prime frequency effects only 207 ms after visibility of the prime and for prime durations of 32 ms yields new time constraints for cognitive processes controlling eye movements during reading. Our variant of the fast priming paradigm provides a new approach to test early influences of word processing on eye movement control during reading.     

Primacy of emotional vs. semantic scene recognition in peripheral vision

Emotional scenes were presented peripherally (5.2° away from fixation) or foveally (at fixation) for 150 ms. In affective evaluation tasks viewers judged whether a scene was unpleasant or not, or whether it was pleasant or not. In semantic categorisation tasks viewers judged whether a scene involved animals or humans (superordinate-level task), or whether it portrayed females or males (subordinate-level task). The same stimuli were used for the affective and the semantic task. Results indicated that in peripheral vision affective evaluation was less accurate and slower than animal/human discrimination, and did not show any advantage over gender discrimination. In addition, performance impairment in the peripheral relative to the foveal condition was greater or equivalent for affective than for semantic categorisation. These findings cast doubts on the specialness and the primacy of affective over semantic recognition. The findings are also relevant when considering the role of the subcortical “low route” in emotional processing.     

Primacy of emotional vs. semantic scene recognition in peripheral vision

Emotional scenes were presented peripherally (5.2° away from fixation) or foveally (at fixation) for 150 ms. In affective evaluation tasks viewers judged whether a scene was unpleasant or not, or whether it was pleasant or not. In semantic categorisation tasks viewers judged whether a scene involved animals or humans (superordinate-level task), or whether it portrayed females or males (subordinate-level task). The same stimuli were used for the affective and the semantic task. Results indicated that in peripheral vision affective evaluation was less accurate and slower than animal/human discrimination, and did not show any advantage over gender discrimination. In addition, performance impairment in the peripheral relative to the foveal condition was greater or equivalent for affective than for semantic categorisation. These findings cast doubts on the specialness and the primacy of affective over semantic recognition. The findings are also relevant when considering the role of the subcortical "low route" in emotional processing.     

Some temporal characteristics of processing during reading

College students read passages displayed on a cathode-ray tube as their eye movements were being monitored. During occasional fixations, all letters to the left of the directly fixated letter or all letters more than four to the right of the fixated letter were replaced by other letters. This replacement occurred either for only the first 100 ms of the fixation or only after the first 100 ms of the fixation. The eye movement data indicated that the eyes can respond to change in the visual stimulus within less than 100 ms and to orthographic irregularity in the text within less than 160 ms. No evidence was found for a left-to-right attentional scan during a fixation. The results were interpreted within the framework of a chronology of processing events occurring during a fixation in reading.     

Eye movement guidance in reading: the role of parafoveal letter and space information

The relation between parafoveal letter and space information in eye movement guidance during reading was investigated in 2 experiments. Contingent upon the reader's fixation, the type of parafoveal information available to the right of fixation was varied by (a) space information only, (b) space information with letter information added at some delay, or (c) letter and space information simultaneously. In addition, the onset of the relevant parafoveal information was delayed between 0 and 250 ms into the fixation. The time course of processing the 2 types of information (letters or spaces) differed, as did the nature of their impact on the eye movement record. Although both letter and space information influenced saccade length and initial landing positions within words, only letter information had an effect on fixation duration. In addition, fixation duration was affected only by information entering within the first 50 ms of the fixation, whereas saccade length was affected by information arriving at any time during the fixation. The results are consistent with a model of eye movement control in which 2 independent processes are operating in tandem to determine when and where to move the eyes during reading.     

Early parafoveal processing in reading Chinese sentences

The possibility that during Chinese reading information is extracted at the beginning of the current fixation was examined in this study. Twenty-four participants read for comprehension while their eye movements were being recorded. A pretarget-target two-character word pair was embedded in each sentence and target word visibility was manipulated in two time intervals (initial 140 ms or after 140 ms) during pretarget viewing. Substantial beginning- and end-of-fixation preview effects were observed together with beginning-of-fixation effects on the pretarget. Apparently parafoveal information at least at the character level can be extracted relatively early during ongoing fixations. Results are highly relevant for ongoing debates on spatially distributed linguistic processing and address fundamental questions about how the human mind solves the task of reading within the constraints of different writing systems.     

场景情境和目标模板在视觉搜索中的交互作用

以真实场景图像中的物体搜索为实验任务, 操纵场景情境和目标模板, 采用眼动技术将搜索过程分为起始阶段、扫描阶段和确认阶段, 考察场景情境和目标模板对视觉搜索过程的影响机制。结果发现, 场景情境和目标模板的作用方式及时间点不同, 二者交互影响搜索的正确率和反应时, 仅场景情境影响起始阶段的时间, 随后二者交互影响扫描阶段和确认阶段的时间及主要眼动指标。作者由此提出了场景情境和目标模板在视觉搜索中的交互作用模型。     

Temporal dynamics of the eye–voice span and eye movement control during oral reading

The distance between eye movements and articulation during oral reading, commonly referred to as the eye–voice span, has been a classic issue of experimental reading research since Buswell (1921). To examine the influence of the span on eye movement control, synchronised recordings of eye position and speech production were obtained during fluent oral reading. The viewing of a word almost always preceded its articulation, and the interval between the onset of a word's fixation and the onset of its articulation was approximately 500 ms. The identification and articulation of a word were closely coupled, and the fixation–speech interval was regulated through immediate adjustments of word viewing duration, unless the interval was relatively long. In this case, the lag between identification and articulation was often reduced through a regression that moved the eyes back in the text. These results indicate that models of eye movement control during oral reading need to include a mechanism that maintains a close linkage between the identification and articulation of words through continuous oculomotor adjustments.     

The limits of visual resolution in natural scene viewing

We examined the limits of visual resolution in natural scene viewing, using a gaze-contingent multiresolutional display having a gaze-centred area-of-interest and decreasing resolution with eccentricity. Twelve participants viewed high-resolution scenes in which gaze-contingent multiresolutional versions occasionally appeared for single fixations. Both detection of image degradation (five filtering levels plus a no-area-of-interest control) in the gaze-contingent multiresolutional display, and eye fixation durations, were well predicted by a model of eccentricity-dependent contrast sensitivity. The results also illuminate the time course of detecting image filtering. Detection did not occur for fixations below 100 ms, and reached asymptote for fixations above 200 ms. Detectable filtering lengthened fixation durations by 160 ms, and interference from an imminent manual response occurred by 400-450 ms, often lengthening the next fixation. We provide an estimate of the limits of visual resolution in natural scene viewing useful for theories of scene perception, and help bridge the literature on spatial vision and eye movement control.     

The effect of the first glimpse at a scene on eye movements during search

Previewing scenes briefly makes finding target objects more efficient when viewing is through a gaze-contingent window (windowed viewing). In contrast, showing a preview of a randomly arranged search display does not benefit search efficiency when viewing during search is of the full display. Here, we tested whether a scene preview is beneficial when the scene is fully visible during search. Scene previews, when presented, were 250 ms in duration. During search, the scene was either fully visible or windowed. A preview always provided an advantage, in terms of decreasing the time to initially fixate and respond to targets and in terms of the total number of fixations. In windowed visibility, a preview reduced the distance of fixations from the target position until at least the fourth fixation. In full visibility, previewing reduced the distance of the second fixation but not of later fixations. The gist information derived from the initial glimpse of a scene allowed for placement of the first one or two fixations at information-rich locations, but when nonfoveal information was available, subsequent eye movements were only guided by online information.     

Comparing naming, lexical decision, and eye fixation times: Word frequency effects and individual differences

Performance on three different tasks was compared: naming, lexical decision, and reading (with eye fixation times on a target word measured). We examined the word frequency effect for a common set of words for each task and each subject. Naming and reading (particularly gaze duration) yielded similar frequency effects for the target words. The frequency effect found in lexical decision was greater than that found in naming and in eye fixation times. In all tasks, there was a correlation between the frequency effect and average response time. In general, the results suggest that both the naming and the lexical decision tasks yield data about word recognition processes that are consistent with effects found in eye fixations during silent reading.     

An adaptive algorithm for fixation,saccade, and glissade detection in eyetracking data

Event detection is used to classify recorded gaze points into periods of fixation, saccade, smooth pursuit, blink, and noise. Although there is an overall consensus that current algorithms for event detection have serious flaws and that a de facto standard for event detection does not exist, surprisingly little work has been done to remedy this problem. We suggest a new velocity-based algorithm that takes several of the previously known limitations into account. Most important, the new algorithm identifies so-called glissades, a wobbling movement at the end of many saccades, as a separate class of eye movements. Part of the solution involves designing an adaptive velocity threshold that makes the event detection less sensitive to variations in noise level and the algorithm settings-free for the user. We demonstrate the performance of the new algorithm on eye movements recorded during reading and scene perception and compare it with two of the most commonly used algorithms today. Results show that, unlike the currently used algorithms, fixations, saccades, and glissades are robustly identified by the new algorithm. Using this algorithm, we found that glissades occur in about half of the saccades, during both reading and scene perception, and that they have an average duration close to 24 msec. Due to the high prevalence and long durations of glissades, we argue that researchers must actively choose whether to assign the glissades to saccades or fixations; the choice affects dependent variables such as fixation and saccade duration significantly. Current algorithms do not offer this choice, and their assignments of each glissade are largely arbitrary.     

藏语阅读知觉广度的眼动研究

不同语体阅读知觉广度的研究由来已久,研究重心多集中于拼音文字和表意文字,已有研究表明阅读知觉广度存在语言加工的特异性。藏语作为拼音文字,同时具有表意文字的特征,是阅读知觉广度研究尚未涉及的语言材料。因此,藏语阅读知觉广度的范围尚不清楚,藏语阅读知觉广度是否也表现出语言加工的特异性也有待证实。为了探测藏语阅读知觉广度的大小,使用Eye Link 1000 Plus型眼动记录仪,以35名在校藏族大学生为被试,采用经典的移动窗口范式,设计了7种窗口(5、9、13、17、21、25和整行)。结果发现,L2R2-L12R12在所有指标的观测值上均存在显著差异,L4R4-L12R12在总注视次数、总注视时间和向右眼跳幅度三个指标的观测值上存在显著差异,L6R6-L12R12在向右眼跳幅度指标的观测值上存在显著差异,L8R8-L12R12在所有指标的观测值上均不存在显著差异,达到了基准水平。结果支持藏族大学生藏语阅读知觉广度的右侧范围大约是注视点右侧4~8个字符的空间。阅读知觉广度存在语言加工的特异性。     

小学二年级学生的字形预视效应

字形信息在汉语阅读中具有重要作用。小学二年级是儿童阅读流畅性发展的重要时期,而对注视点右侧字词的预加工及所获得的预视效应是影响流畅阅读的重要因素。本研究考察了字形信息在二年级学生预加工中的作用。实验1采用副中央凹启动范式发现,在词汇识别任务中,二年级学生在100ms副中央凹启动时间下,表现出字形预视效应。实验2采用边界范式发现,在句子默读任务中,二年级学生能够获取副中央凹处的字形信息。结果表明,二年级学生在阅读中能够使用副中央凹处的字形信息,促进随后中央凹处的词汇加工。     

Direct control of fixation times in scene viewing: Evidence from analysis of the distribution of first fixation duration

Participants' eye movements were monitored in two scene viewing experiments that manipulated the task-relevance of scene stimuli and their availability for extrafoveal processing. In both experiments, participants viewed arrays containing eight scenes drawn from two categories. The arrays of scenes were either viewed freely (Free Viewing) or in a gaze-contingent viewing mode where extrafoveal preview of the scenes was restricted (No Preview). In Experiment 1a, participants memorized the scenes from one category that was designated as relevant, and in Experiment 1b, participants chose their preferred scene from within the relevant category. We examined first fixations on scenes from the relevant category compared to the irrelevant category (Experiments 1a and 1b), and those on the chosen scene compared to other scenes not chosen within the relevant category (Experiment 1b). A survival analysis was used to estimate the first discernible influence of the task-relevance on the distribution of first-fixation durations. In the free viewing condition in Experiment 1a, the influence of task relevance occurred as early as 81 ms from the start of fixation. In contrast, the corresponding value in the no preview condition was 254 ms, demonstrating the crucial role of extrafoveal processing in enabling direct control of fixation durations in scene viewing. First fixation durations were also influenced by whether or not the scene was eventually chosen (Experiment 1b), but this effect occurred later and affected fewer fixations than the effect of scene category, indicating that the time course of scene processing is an important variable mediating direct control of fixation durations.