An integrated model of eye movements and visual encoding

Recent computational models of cognition have made good progress in accounting for the visual processes needed to encode external stimuli. However, these models typically incorporate simplified models of visual processing that assume a constant encoding time for all visual objects and do not distinguish between eye movements and shifts of attention. This paper presents a domain-independent computational model, EMMA, that provides a more rigorous account of eye movements and visual encoding and their interaction with a cognitive processor. The visual-encoding component of the model describes the effects of frequency and foveal eccentricity when encoding visual objects as internal representations. The eye-movement component describes the temporal and spatial characteristics of eye movements as they arise from shifts of visual attention. When integrated with a cognitive model, EMMA generates quantitative predictions concerning when and where the eyes move, thus serving to relate higher-level cognitive processes and attention shifts with lower-level eye-movement behavior. The paper evaluates EMMA in three illustrative domains — equation solving, reading, and visual search — and demonstrates how the model accounts for aspects of behavior that simpler models of cognitive and visual processing fail to explain.     

Attention Is Required to Coordinate Reaching and Postural Stability during Upper Limb Movements Generated While Standing

Abstract

In the present study we investigated how attention contributes to the interaction between reach planning and execution, and postural control. Reaching movements were generated while standing and were performed either in isolation or in conjunction with a secondary reaction time (RT) task. In addition, to better understand how online movement control is affected by this interaction, the reaching movements could be unexpectedly perturbed medial-laterally. Postural kinetic, arm kinematic and RT, and secondary RT measures were used to characterize the responses. Results indicate task performance worsened when both the reaching and secondary tasks were completed simultaneously. Our results imply the generation of reaching movements while standing requires attentional resources to properly coordinate the interaction between the reaching task and postural control.     

阅读理解中的代词加工:先行词的距离与性别刻板印象的作用

采用眼动技术,本研究探讨了阅读理解中代词的加工机制.读者阅读包含代词的文本,代词的性别与先行词的性别刻板印象一致或违背,同时其和先行词间的距离或远或近,记录被试阅读文本的眼动轨迹.结果发现,与一致条件相比,违背条件的加工时间更长.当代词和先行词间距离较近时,一致性效应在关键代词区的反映早期加工的眼动指标上即出现,而当二者间距离较远时,一致性效应在更后的位置(代词后那一区域)出现,并且只出现在反映晚期加工的眼动指标上.此外,与远距离一致条件相比,近距离一致条件下代词后那一区域的阅读时间更长.上述结果表明,性别刻板印象以及距离在代词加工皆发挥重要作用,而且性别刻板印象产生的影响在时程上因距离的不同而不同.这一结果在一定程度上为语言理解的交互作用理论提供了证据.     

Infants Anticipate Others' Social Preferences

In the current eye‐tracking study, we explored whether 12‐month‐old infants can predict others' social preferences. We showed infants scenes in which two characters alternately helped or hindered an agent in his goal of climbing a hill. In a control condition, the two characters moved up and down the hill in identical ways to the helper and hinderer but did not make contact with the agent; thus, they did not cause him to reach or not reach his goal. Following six alternating familiarization trials of helping and hindering interactions (help–hinder condition) or up and down interactions (up–down condition), infants were shown one test trial in which they could visually anticipate the agent approaching one of the two characters. As predicted, infants in the help–hinder condition made significantly more visual anticipations toward the helping than hindering character, suggesting that they predicted the agent to approach the helping character. In contrast, infants revealed no difference in visual anticipations between the up and down characters. The up–down condition served to control for low‐level perceptual explanations of the results for the help–hinder condition. Thus, together the results reveal that 12‐month‐old infants make predictions about others' behaviour and social preferences from a third‐party perspective. Copyright © 2012 John Wiley & Sons, Ltd.     

阅读中的注意分配:序列与平行之争

阅读中的注意分配问题是区分目前占主导地位的两类眼动控制模型的核心因素,基于序列分布假设的眼动控模型与基于平行注意分布的眼动控制模型在对眼动行为的预测中存在一些显著的差异,譬如一次注视下能否深度加工知觉广度内的一个以上词汇的信息.文章围绕两类模型对该问题的不同预测,深入探讨了两类模型的核心差异以及相关实验证据,并概括其它相关领域中在知觉广度内关于序列与平行注意分布的研究,以及对建构中文眼动控制模型的重要意义.     

背景性质对7-10岁自闭症谱系障碍儿童面孔搜索与加工的作用

为了考察背景性质对ASD者搜索面孔的影响,设计两个眼动实验任务,要求14名7~10岁ASD儿童和20名同年龄正常儿童观看图片。实验一采用将面孔嵌入风景图片中引起语义不一致的刺激;实验二采用含有面孔的无意义背景乱序图片刺激。结果发现：（1）面孔与背景语义不一致并不能促进ASD儿童对面孔的搜索;（2）乱序背景对ASD儿童面孔搜索与加工没有产生干扰作用,但使正常儿童的搜索时间变长;（3）一旦觉察到面孔后,ASD儿童对面孔的注视时间少于正常儿童。表明正常儿童对面孔的搜索与加工受背景性质的影响,而ASD儿童不受背景性质的影响;一旦发现面孔,ASD儿童的注意维持较短,但面孔加工模式与正常儿童相似。     

中文书写者字迹识别的眼动研究

采用眼动技术,以不同整体书写风格的字迹为实验材料,探讨中文字迹识别的眼动模式。实验结果显示：随着整体书写风格一致性的变化,被试识别不同书写者中文字迹的反应时、注视次数,眼跳次数,兴趣区数及落入兴趣区的比率均表现出显著性差异。结论：（1）识别中文字迹依赖字迹整体书写风格;（2）中文字迹识别模式：在识别字迹时,优先采用字迹整体书写风格识别不同的字迹;（3）中文字迹识别属于图像识别加工。     

Bilateral saccadic eye movements and tactile stimulation,but not auditory stimulation,enhance memory retrieval

Recent research has shown superior memory retrieval when participants make a series of horizontal saccadic eye movements between the memory encoding phase and the retrieval phase compared to participants who do not move their eyes or move their eyes vertically. It has been hypothesized that the rapidly alternating activation of the two hemispheres that is associated with the series of left–right eye movements is critical in causing the enhanced retrieval. This hypothesis predicts a beneficial effect on retrieval of alternating left–right stimulation not only of the visuomotor system, but also of the somatosensory system, both of which have a strict contralateral organization. In contrast, this hypothesis does not predict an effect, or a weaker effect, on retrieval of alternating left–right stimulation of the auditory system, which has a much less lateralized organization. Consistent with these predictions, we replicated the horizontal saccade-induced retrieval enhancement (Experiment 1) and showed that a similar retrieval enhancement occurs after alternating left–right tactile stimulation (Experiment 2). Furthermore, retrieval was not enhanced after alternating left–right auditory stimulation compared to simultaneous bilateral auditory stimulation (Experiment 3). We discuss the possibility that alternating bilateral activation of the left and right hemispheres exerts its effects on memory by increasing the functional connectivity between the two hemispheres. We also discuss the findings in the context of clinical practice, in which bilateral eye movements (EMDR) and auditory stimulation are used in the treatment of post-traumatic stress disorder.     

The time course of predictability effects in reading: Evidence from a survival analysis of fixation durations

To investigate the time course of predictability effects in reading, the present study examined distributions of first-fixation durations on target words in a low predictability versus a high predictability prior context. In a replication of Staub (2011), ex-Gaussian fitting demonstrated that the low predictability distribution was significantly shifted to the right of the high predictability distribution in the absence of any contextual differences in the degree of skew. Extending this finding, the present study used a survival analysis technique to demonstrate a significant influence of predictability on fixation duration as early as 140 ms from the start of fixation, which is similar to prior results obtained with the word frequency variable. These results provide convergent evidence that lexical variables have a fast acting influence on fixation durations during reading. Implications for models of eye-movement control are discussed.     

Content,not context,facilitates memory for real-world scenes

ABSTRACT

Can eye movements tell us whether people will remember a scene? In order to investigate the link between eye movements and memory encoding and retrieval, we asked participants to study photographs of real-world scenes while their eye movements were being tracked. We found eye gaze patterns during study to be predictive of subsequent memory for scenes. Moreover, gaze patterns during study were more similar to gaze patterns during test for remembered than for forgotten scenes. Thus, eye movements are indeed indicative of scene memory. In an explicit test for context effects of eye movements on memory, we found recognition rate to be unaffected by the disruption of spatial and/or temporal context of repeated eye movements. Therefore, we conclude that eye movements cue memory by selecting and accessing the most relevant scene content, regardless of its spatial location within the scene or the order in which it was selected.