视知觉无意识加工中的形状优势效应

研究了视知觉无意识加工中是否存在形状优势效应。被试为天津师范大学本科生60名。仪器为pentium lll高分辨率计算机．程序用E-prime心理实验软件系统编制而成。在实验1中,用信号检测论技术发现．当启动图形呈现时间为20ms时．被试是不能觉知到该图形的。在实验2和3中．被试的任务分别是判断图形的形状和颜色,用MANOVA分析启动图形对靶图形的启动效应时发现．启动图形的颜色线索不会影响靶图形的形状判断,但启动图形的形状线索却能抑制或促进靶图形的颜色判断。实验证据提示．在判断物体整体特征时,无意识知觉具有形状优势效应。     

Evidence Supporting the Importance of Peripheral Visual Information for the Directional Control of Aiming Movement

The focus of the present study was on determining whether the high level of directional accuracy found in aiming studies in which the subjects can see their hand in the visual periphery supports the existence of a kinetic visual channel or, rather, the advantage of binocular over monocular vision for movement directional control. The limits of this kinetic visual channel were also explored. The results of the 1st experiment indicated that seeing one's hand in the visual periphery is sufficient to ensure optimal directional aiming accuracy. Further, no differences in aiming accuracy were noted between monocular and binocular vision. These results supported the existence of a visual kinetic channel. In the 2nd experiment, whether this kinetic visual channel would operate with movements slower (55°/s) than those usually used in studies that had proved its existence (over 110°/s) was determined. The results indicated that this visual kinetic channel was operative even at relatively slow movement velocities. Central vision of the hand seemed to be used for on-line directional control of relatively slow movements.     

From Fragments to Geometric Shape: Changes in Visual Object Recognition Between 18 and 24 Months

ABSTRACT— Visual object recognition is foundational to processes of categorization, tool use, and real-world problem solving. Despite considerable effort across many disciplines and many specific advances, there is no comprehensive or well-accepted account of this ability. Moreover, none of the extant approaches consider how human object recognition develops. New evidence indicates a period of rapid change in toddlers' visual object recognition between 18 and 24 months that is related to the learning of object names and to goal-directed action. Children appear to shift from recognition based on piecemeal fragments to recognition based on geometric representations of three-dimensional shape. These findings may lead to a more unified understanding of the processes that make human object recognition as impressive as it is.     

Force Control of Ankle Dorsiflexors in Young Adults: Effects of Bilateral Control and Leg Dominance

Abstract

We investigated whether bilateral lower-limb control and leg dominance affect force control ability in 15 healthy young adults (9 males and 6 females, age =26.8?±?4.1 years). Participants performed isometric ankle dorsiflexion force control tasks, matching a visual target (10% of maximal effort) as quickly and precisely as possible in ballistic and tonic tasks. Performance was evaluated using force error, force steadiness, amount of muscle activity of the tibialis anterior, and response time characteristics. Results showed no significant effects of leg dominance during both ballistic and tonic tasks, while bilateral condition resulted in significantly larger error, less force steadiness, compared to unilateral condition, and only during the tonic task. Consequently, bilateral control, specifically in tasks utilizing feedback control (i.e., tonic task) might affect force control ability, possibly because of the interhemispheric inhibition to meet bilateral task complexity and integrate afferent bilateral sensory information from both right and left legs.     

On the Role of Visual Afferent Information for the Control of Aiming Movements Toward Targets of Different Sizes

The authors investigated (a) whether the specificity of practice hypothesis is mediated by the importance of visual afferent information for the control of manual aiming movements and (b) how movement planning and online correction processes to the movement initial impulse are affected by the withdrawal of visual information in transfer. In acquisition, participants (N = 40) aimed at targets of different sizes in a full-vision or in a target-only condition before being transferred to a target-only condition without knowledge of results. The results supported the hypothesis that learning is specific to the source or sources of afferent information that are more likely to ensure optimal performance. The results also suggested that individuals will not always use visual afferent information more extensively when aiming at a small rather than at a large target. Instead, in a temporally constrained task, the relative efficiency of visually based corrections appears to mediate how exclusively an individual will rely on online visual afferent information for movement control. Finally, the detailed kinematic analysis performed in the present study clearly indicated that online modifications to the movement primary impulse are possible, arguing for a continuous or pseudo-continuous control of relatively slow aiming movements on the basis of visual afferent input.     

Visual dominance in the pigeon

In Experiment 1, three pigeons were trained to obtain grain by depressing one foot treadle in the presence of a 746-Hertz tone stimulus and by depressing a second foot treadle in the presence of a red light stimulus. Intertrial stimuli included white light and the absence of tone. The latencies to respond on auditory element trials were as fast, or faster, than on visual element trials, but pigeons always responded on the visual treadle when presented with a compound stimulus composed of the auditory and visual elements. In Experiment 2, pigeons were trained on the auditory-visual discrimination task using as trial stimuli increases in the intensity of auditory or visual intertrial stimuli. Again, pigeons showed visual dominance on subsequent compound stimulus test trials. In Experiment 3, on compound test trials, the onset of the visual stimulus was delayed relative to the onset of the auditory stimulus. Visual treadle responses generally occurred with delay intervals of less than 500 milliseconds, and auditory treadle responses generally occurred with delay intervals of greater than 500 milliseconds. The results are discussed in terms of Posner, Nissen, and Klein's (1976) theory of visual dominance in humans.     

视觉表象扫描的概念控制

将表象扫描和概念提示范式相结合, 在三个实验中通过考察概念控制下表象扫描加工中的参照系冲突效应以及概念参照系的优先性, 进而揭示表象扫描加工中的自上而下控制机制。结果发现：(1) 正立或旋转方位汉字提示下表象扫描加工中出现了参照轴效应, 箭头提示下不存在这种效应, 表明不同提示引发了不同空间关系计算过程; (2) 在表象扫描概念控制过程中, 概念参照系、环境(重力)参照系及提示汉字内在参照系同时被激活, 它们可能处于不同冲突状态, 解决这些冲突具有不同认知代价; (3) 在解决不同参照系冲突过程中, 反映自上而下加工的概念参照系总能通过抑制其它参照系而取得优先地位, 表明人的认知系统能够对表象加工进行自上而下的主动控制, 这种主动控制反映了一种执行功能。     

Effects of Visual Error Timing on Smooth Pursuit Gain Adaptation in Humans

Smooth pursuit (SP) is one of the precise oculomotor behaviors when tracking a moving object. Adaptation of SP is based on a visual-error driven motor learning process associated with predictable changes in the visual environment. Proper timing of a sensory signal is an important factor for adaptation of fine motor control. In this study, we investigated whether visual error timing affects SP gain adaptation. An adaptive change in SP gain is produced experimentally by repeated trials of a step-ramp tracking with 2 different velocities (double-velocity paradigm). The authors used the double-velocity paradigm where target speed changes 400 or 800 ms after the target onset. The results show that SP gain changed in a certain time window following adaptation. The authors suggest that SP adaptation shown in this study is associated with timing control mechanisms.     

认知任务对直立姿势的视觉控制的影响

为揭示认知任务对直立姿势的视觉控制的影响, 本研究采用双重任务的方法, 要求18名健康的成年被试在4种条件(2认知条件×2视觉条件)下尽力保持直立姿势的稳定。姿势动摇的测量采用头顶拍摄的方法并计算误差均方根、平均速度以及Romberg商数。研究结果显示认知任务和视觉条件之间的交互作用显著, 而且当有认知任务时姿势动摇的Romberg商数显著降低。这些结果说明认知任务抑制了直立姿势控制过程中的视觉加工。     

基于名人面孔视觉特征和语义信息的视觉统计学习

视觉统计学习是指个体依据视觉刺激之间的转接概率来掌握统计规律的过程。本研究通过5个实验探讨了个体基于名人面孔视觉特征和语义信息进行视觉统计学习的加工机制。每个实验均包括熟悉(学习)和测试两个阶段：在熟悉阶段, 让被试观看名人面孔并完成重复图片探测的无关任务; 在测试阶段, 让被试进行二选一迫选任务。其中, 实验1和2分别考察基于名人面孔视觉特征和语义信息的视觉统计学习效果; 实验3分别考察基于名人面孔视觉特征和语义信息视觉进行统计学习的精确性; 实验4进一步考察基于名人面孔视觉特征和语义信息进行视觉统计学习的时间特征; 实验5验证基于名人面孔视觉特征的视觉统计学习具有面孔特异性。结果表明：个体能同时基于名人面孔视觉特征和语义信息进行精确的视觉统计学习; 基于正立名人面孔的视觉统计学习效果显著高于基于倒置名人面孔的视觉统计学习效果; 虽然基于视觉特征和语义信息的统计加工都具有一致的精确性, 但后者需要更多的加工时间。这提示：基于名人面孔视觉特征的视觉统计学习具有面孔特异性, 个体基于名人面孔视觉特征和语义信息的视觉统计学习过程是分离的, 统计运算发生于面孔特征加工完成之后。     

Specificity of Learning in a Video-Aiming Task: Modifying the Salience of Dynamic Visual Cues

The authors investigated whether the salience of dynamic visual information in a video-aiming task mediates the specificity of practice. Thirty participants practiced video-aiming movements in a full-vision, a weak-vision, or a target-only condition before being transferred to the target-only condition without knowledge of results. The full- and weak-vision conditions resulted in less endpoint bias and variability in acquisition than did the target-only condition. Going from acquisition to transfer resulted in a large increase in endpoint variability for the full-vision group but not for the weak-vision or target-only groups. Kinematic analysis revealed that weak dynamic visual cues do not mask the processing of other sources of afferent information; unlike strong visual cues, weak visual cues help individuals calibrate less salient sources of afferent information, such as proprioception.     

Cognitive Control of Attentional Guidance by Visual and Verbal Working Memory Representations

Both visual and verbal information in working memory guide visual attention toward a memory‐matching object. We tested whether: (a) visual and verbal representations have different effects on the deployment of attention; and (b) both types of representations can be used equally in a top‐down manner. We asked participants to maintain a visual cue or a verbal cue at the beginning of each trial, and ended with a memory task to ensure that each cue was represented actively in working memory. Before the memory task, a visual search task appeared where validity was manipulated as valid, neutral, or invalid. We also manipulated the probability of valid trials (20%, 50%, and 80%), which had been told to the participants prior to the task. Consistent with earlier findings, attentional guidance by visual representations was modulated by the probability. We also found that this was true for verbal representations, and that these effects did not differ between representation types. These results suggest that both visual and verbal representations in working memory can be used strategically to control attentional guidance.     

成年雄性斑胸草雀高级发声中枢鸣声控制的右侧优势

鸣禽是研究语言功能的动物模型。鸣禽端脑的高级发声中枢(high vocal center, HVC)与人类布洛卡氏区具有功能同源性。利用电损毁与声谱分析相结合的方法, 对成年雄性斑胸草雀两侧HVC分别进行电损毁, 观察HVC控制鸣声的侧别差异。结果表明, 损毁左侧HVC对长鸣和鸣曲的频域和声强特征均无显著性影响。损毁右侧HVC导致长鸣的振幅、调频、幅度调制显著减小(p < 0.05), 鸣曲的振幅、平均频率、峰频率显著减小(p < 0.05)。损毁双侧HVC后均引起鸣曲时域特征的改变, 暗示鸣曲时域特征的编码需要两侧半球鸣唱系统的整合。HVC在控制鸣声频域和声强特征上具有右侧优势, 但对鸣曲时域特征的控制需要两侧HVC的共同参与。     

The Role of Visual Feedback about Motion of the Ground on Postural Sway

Abstract

We asked whether body sway would be influenced by visual information about motion of the ground surface. On a ship at sea, standing participants performed a demanding visual search task or a simple visual inspection task. Display content was stationary relative to the ship or relative to the Earth. Participants faced the ship’s bow or its port side. Performance on the visual search task was representative of terrestrial studies. Body sway was greater during viewing of the Earth Stationary displays than during viewing of the Ship Stationary displays. We discuss possible implications of these results for theoretical and applied issues.     

Biomechanical Study of Tandem Stance in Healthy Young Adults: Effects of Weight-Bearing and Limb Dominance

Postural strategies of healthy young adults to control tandem stance were investigated through the calculation of the relative contribution of the two loading-unloading (LU) and pressure-distribution (PD) mechanisms and the two legs for controlling the resultant center-of-pressure (CP_Res) displacements. Weight-bearing asymmetry and limb dominance were also studied. For antero-posterior and medio-lateral CP_Res displacements, LU and PD mechanisms mainly contribute, respectively. A significant LU contribution is nonetheless observed for medio-lateral control, due to a lateral gap between the CP positions under each foot despite a strict sagittal alignment for the two feet. Moreover, for medio-lateral control, the respective involvement of the two legs is related to the level of weight-bearing asymmetry, whereas the front leg mainly controls the antero-posterior sway. By specifying potential effects of body-weight asymmetry and limb dominance, to a better testing of patients with deficiencies in lateral sway control.     

客体在视觉工作记忆中的存储机制

采用变化觉察范式,通过两个实验对不同类型视觉信息在工作记忆中的存储机制进行了探讨。实验一中要求记忆的客体由颜色和形状两基本特征构成;实验二中的客体为具有不同颜色及开口朝向的兰道环。通过观察检测项变化方式对记忆绩效的影响,获得以下结论:（1）对颜色和形状两基本特征的存储以整合客体为单位;（2）兰道环的颜色与开口朝向信息难以以整合客体方式存储。笔者推测,视觉工作记忆中存储的整合客体并非如现有理论假设的,是在集中注意参与下创建的,而是由并行加工阶段所获信息构成;客体中所含需集中注意提取的细节特征信息难以与其基本特征信息整合于该客体表征     

The Effects of Initial Habit Strength Differences Upon Performance in a Coaction Situation

The present investigation examined the effects of initial habit strength differences upon performance in a coaction situation. During a training session, a habit-strength hierarchy was developed in each of three groups through the establishment of a differential response expectancy for each of four alternative responses. In a subsequent test session, both performance and consistency of performance were affected by the pretraining on the correct habit. However, there was no statistical support for the hypothesis that coaction would interact with the habit-strength condition resulting in an improvement in the coaction/habit-correct group and a decrement in the coaction/habit-incorrect group. Similarly, no differences were found between the coaction and alone conditions.     

视觉客体工作记忆中图形特征存储与捆绑时程

采用单探测变化检测范式,考察了形状和颜色客体在工作记忆中的表征方式、特征检测类型及初始刺激呈现时间对工作记忆表征的影响。结果表明:(1)视觉客体工作记忆的表征包括两个水平,首先是对客体的特征进行加工存储,其次才是对特征的捆绑;(2)不同特征的加工时间不同,颜色的加工完成的较早,记忆效果好,而形状的加工完成的较晚,记忆效果也差,表现出颜色的子系统优势;(3)特征的捆绑不是必需的,只有在任务需要时才进行,并且捆绑的过程符合特征捆绑的双阶段理论。     

Dominance,aggression, and the functional use of space in institutionalized female adolescents

This is a study of an institutionalized group of female adolescents observed for a nine-week period. These girls were observed to determine the characteristics of their dominance relations and how, in turn, this aspect of their social environment was related to use of their physical environment. Correlational analyses between observational and sociometric data suggested that dominance rank was based upon the frequency of being the recipient of a dominance act. Fewer dominance acts were initiated against higher ranking girls. Dominance ranking was not based upon frequency of initiating a dominance act towards others. Higher ranking girls were the ones most frequently observed alone in their own bedroom. Bedrooms were highly desiuable areas used for grooming (eg, setting hair, ironing clothes, putting on cosmetics, resting) as girls sought to gain popularity with the institution's male population. Comparison of results with findings in similar studies on male adolescents suggest some tentative generalizations as to sex difference in dominance and territoriality.     

视觉特征提取加工中的认知可塑性

本研究采用“加因素法”研究范式,通过两个实验分别检测20名飞行员和lO名老年被试及其相应控制组在视觉特征提取任务上的认知加工水平,旨在探讨视觉特征提取这一高水平视觉表象加工上的认知可塑性水平。研究结果表明,视觉特征提取加工既表现出了随外界系统训练而发生功能增强的练习效应,也表现出了随年老化过程而发生相应功能显著改变的年龄效应。研究提示,由于受大脑神经细胞活动特性改变的影响,视觉特征提取加工更多地表现出了可塑性或易变性相对较高的认知特性。结合相关的工作基础,研究结果还进一步证实高水平视觉认知加工所表现出的练习效应和年龄效应在大脑神经网络上的分布是不平衡的。本研究不仅对于揭示高水平视觉表象加工的认知特性具有重要的理论意义,而且在实践中对于建立飞行员、宇航员等特殊职业人员的选拔模型以及揭示飞行空间定向障碍的认知机制也具有重要的应用价值。