视觉信息分布调节信息整合策略：来自眼动的证据

以空白单元格定位为实验任务,操纵序列点阵的分布,考察视觉短时记忆与视知觉的信息整合机制。实验一发现任务正确率与点阵1的圆点数呈近似U形关系。实验二发现在拐点前后被试的眼动模式从偏向于注视圆点位置转为偏向于注视空格位置。因此,视觉信息的分布模式调节整合策略,当处于视觉短时记忆中的圆点数在其容量之内时,采用图像—知觉整合策略,反之,则采用转换—比较策略。     

动词隐含因果关系在代词解决中的时间进程的眼动研究

以初中三年级学生为被试,利用Eye-LinkⅡ型眼动仪,探讨动词隐含因果关系在代词解决中的作用及其时间进程。结果表明,动词隐含因果关系在代词解决中起重要作用,其时间进程是一个延缓加工的过程,结果支持了整合假设。同时还发现被试工作记忆容量的大小对代词解决任务产生一定的影响。     

视觉选择过程中眼跳与注意关系的理论进展

视觉选择的过程包含两种途径:眼跳行动和注意转移,两者对于视觉选择目标物的加工都有促进作用。鉴于此,视觉研究领域产生大量关于二者关联如何的实验研究,大部分研究者认为眼跳和注意转移存在密切联系。该文将关于两者关系的重要理论进行了综合阐述和简要比较,主要介绍五种理论假说:眼动准备假说、动前假说、顺序注意模型、视觉注意模型和竞争整合模型。     

A Test of the Schema Theory of Discrete Motor Learning

The recall schema in a response class of discrete movements was investigated, with variability of practice being manipulated before transfer to a new instance in the response class. After the transfer, the varied-practice group performance was superior to the continuous practice group. The interaction of the low-and high-variability groups from training to recall performance supported the prediction that a group with more variable training would exhibit an increased rate of learning when introduced to a new instance of the response class. After two days, the superiority of the high-variability group over the low disappeared, suggesting the memory representations of the two groups were no different under withdrawal of knowledge of results.     

Near,Far, or In Between?—Target Edges and the Transport Component of Prehension

It is well known that during visually guided prehension movements the peak velocity of the arm is scaled for object distance (e.g., Gentilucci et al., 1991; Jakobson & Goodale, 1991; Servos, Goodale, & Jakobson, 1992). Those movements are being directed not to single points in space, however, but rather to objects with extent. Thus, object distance must be computed relative to some particular point on the object. Whether that point corresponds to the location of a particular edge, for example, has not been clearly demonstrated. In the present study, subjects (N = 9) were presented with a series of oblong blocks positioned at different locations. Peak velocity increased with object size for reaches in which different-sized objects had their near edges lined up; in contrast, the peak velocities of reaches directed to objects of different sizes did not differ when the far edges of the objects were lined up. The present study, therefore, provided confirmation that subjects calibrate the peak velocity of their reaches relative to the far edge of a target object.     

The Use of Prescanning in the Parameterization of Sequential Pointing and Reaching Movements

The accuracy of reaching movements improves when active gaze can be used to fixate on targets. The advantage of free gaze has been attributed to the use of ocular proprioception or efference signals for online control. The time course of this process, however, is not established, and it is unclear how far in advance gaze can move and still be used to parameterize subsequent movements. In this experiment, the authors considered the advantage of prescanning targets for both pointing and reaching movements. The authors manipulated the visual information and examined the extent to which prescanning of targets could compensate for a reduction in online visual feedback. In comparison with a conventional reaching/pointing condition, the error in pointing was reduced, the eye-hand lead decreased, and both the hand-closure time and the size of the maximum grip aperture in reaching were modulated when prescanning was allowed. These results indicate that briefly prescanning multiple targets just prior to the movement allows the refinement of subsequent hand movements that yields an improvement in accuracy. This study therefore provides additional evidence that the coordinate information arising from efference or ocular-proprioceptive signals can, for a limited period, be buffered and later used to generate a sequence of movements.     

生存优势效应的理论解释

生存优势效应指对学习材料进行“生存加工”,其提取正确率最高。研究者试图用主题加工、一致性效应、情绪加工和自然选择等理论对生存优势效应进行解释。研究发现主题加工、一致性效应和情绪加工不足以说明生存优势现象,自然选择理论似乎可以更好地对此加以解释,但目前自然选择理论尚缺乏直接的实验证据支持。文章结合已有研究具体分析了最近的未来研究应该关注的焦点问题,例如,自然选择理论的直接证明,并对直接证明的方案等进行了尝试性的讨论。     

序列语义的类别一致性关系能否进行无意识整合？

阈下语义之间能否进行整合,最近的研究给出了不同的结果。当多个阈下语义词语同时呈现时显示出无意识语义整合效应,但是当序列呈现时没有观察到无意识整合效应。本研究在保留同时呈现方法优点（不同空间呈现位置）的情况下研究了序列呈现的不同汉字词语之间能否产生无意识语义类别关系整合。在实验1中,两个相同或不同类别的词语作为阈下启动刺激先后在两侧呈现,且第一个词语消失后第二词语马上出现,结果显示出无意识语义类别整合效应。实验2延长了两个阈下启动词语之间的时间间隔,结果未发现无意识语义类别整合效应。另外,实验3进一步排除了实验1中第一个启动词语的视觉残留,结果也未观察到显著的无意识语义类别整合效应,说明实验1中观察到的无意识整合效应是视觉残留所致。综合三个实验结果表明,两个阈下词语之间的语义类别一致性关系只有在同时呈现这种特殊条件下才能进行无意识整合加工,说明了短时间维度对于无意识语义关系整合的重要性。     

序列语义的类别一致性关系能否进行无意识整合？

阈下语义之间能否进行整合,最近的研究给出了不同的结果。当多个阈下语义词语同时呈现时显示出无意识语义整合效应,但是当序列呈现时没有观察到无意识整合效应。本研究在保留同时呈现方法优点（不同空间呈现位置）的情况下研究了序列呈现的不同汉字词语之间能否产生无意识语义类别关系整合。在实验1中,两个相同或不同类别的词语作为阈下启动刺激先后在两侧呈现,且第一个词语消失后第二词语马上出现,结果显示出无意识语义类别整合效应。实验2延长了两个阈下启动词语之间的时间间隔,结果未发现无意识语义类别整合效应。另外,实验3进一步排除了实验1中第一个启动词语的视觉残留,结果也未观察到显著的无意识语义类别整合效应,说明实验1中观察到的无意识整合效应是视觉残留所致。综合三个实验结果表明,两个阈下词语之间的语义类别一致性关系只有在同时呈现这种特殊条件下才能进行无意识整合加工,说明了短时间维度对于无意识语义关系整合的重要性。     

A test of torque-control and equilibrium-point models of motor control

Based upon predictions of equilibrium-point (EP) models of motor control, a recent article by Jaric et al. (1999) [Human Movement Sciences, 18, 49–66] reported that the peak velocity (PV) of an inertially loaded single degree-of-freedom elbow movement was not altered to a statistically distinguishable degree by the accuracy of the subject's expectation about the size of the load. They concluded that their results confirmed their EP models and were incompatible with what they described as torque-control models. A review of the literature and analysis of a more extensive set of data does not support that conclusion. To the contrary, if the actual load is heavier (or lighter) than expected, it is moved more slowly (or faster) than it would have been, had expectation matched reality. Torque-control models predict those consequences, EP models do not.     

Characteristics of Unintentional Movements by a Multijoint Effector

The authors explored the phenomenon of unintentional changes in the equilibrium state of a multijoint effector produced by transient changes in the external force. The subjects performed a position-holding task against a constant force produced by a robot and were instructed not to intervene voluntarily with movements produced by changes in the robot force. The robot produced a smooth force increase leading to a hand movement, followed by a dwell time. Then, the force dropped to its initial value leading to hand movement toward the initial position, but the hand stopped short of the initial position. The undershoot magnitude increased linearly with the peak hand displacement and exponentially with dwell time (time constant of about 1 s). For long dwell times, the hand stopped at about half the total distance to the initial position. The authors interpret the results as consequences of a drift of the referent hand coordinate. Our results provide support for back-coupling between the referent and actual body configurations during multijoint actions and produce the first quantitative analysis of this phenomenon. This mechanism can also explain the phenomena of slacking and force drop after turning visual feedback off during accurate force production task.     

观察不同形状和颜色时眼运动的顺序性

实验使用EVM3200型眼动仪测量被试在观察四种不同形状和四种不同颜色时眼运动轨迹的特点,来研究人眼运动的顺序性。结果表明：人眼在观察不同形状和颜色时,眼运动具有时间序列和空间序列的特性;形状和颜色一样具有诱目性序列特征;眼运动凝视点受到刺激所处空间位置的明显影响;首次凝视点是研究眼运动的重要变量。     

Control of Trajectory Modifications in Target-Directed Reaching

Human reaching movements to fixed and displaced visual targets were recorded and compared with simulated movements generated by using a two-joint arm model based on the equilibrium-point (EP) hypothesis (λ model) of motor control (Feldman, 1986). The aim was to investigate the form of central control signals underlying these movements. According to this hypothesis, movements result from changes in control variables that shift the equilibrium position (EP) of the arm. At any time, muscle activations and forces will depend on the difference between the arm's EP and its actual position and on the limb's velocity. In this article, we suggest that the direction of EP shift in reaching is specified at the hand level, whereas the rate of EP shift may be specified at the hand or joint level. A common mechanism underlying reaching to fixed and displaced targets is proposed whereby the EP of the hand shifts in a straight line toward the present target. After the target is displaced, the direction of the hand EP shift is modified toward the second target. The results suggest that the rate of shift of the hand EP may be modified for movements in different parts of the work space. The model, with control signals that vary in a simple fashion over time, is able to generate the kinematic patterns observed empirically.     

Effects of Training on Endurance in Hanging by The Hands

The effect of training on endurance in hanging by the hands from a horizontal bar was examined by timing the duration of such hanging in six male and five female subjects each weekday for 2 weeks. A significant increase in endurance was observed. The results, both subjective and objective, indicated the most important factors in the training to be increased psychological endurance of discomfort and increased muscular strength and efficiency.     

邻近效应对多媒体学习中图文整合的影响:线索的作用

在多媒体学习中图文排列的邻近或远离会影响学习的效果。本研究操纵了多媒体呈现的图文排列位置,采用颜色作为线索引导注意,探讨了线索有无和图片-文字的空间位置对多媒体学习图文整合的影响。结果发现:图文邻近呈现时的保持测验和迁移测验成绩好于图文远离呈现,图文邻近呈现时学习者对关键兴趣区的进出次数更多,体现出以文字为导向的阅读模式。线索并没有单独影响学习成绩和注意分配;但结合图文位置后,发现有线索时图文邻近学习材料的注视次数、进出关键兴趣区的次数显著多于图文远离。研究认为:图文的邻近效应不仅提高学习者对知识的识记和理解,同时也影响了学习者的注意分配过程,图文邻近呈现有助于图片和文本信息的注意联结和知识整合;线索能使邻近效应得到凸显,更好地促进图文信息的注视加工,但没有改进学习的效果。