身份交换对多身份追踪表现的影响

本研究探讨了身份交换对多身份追踪表现的影响。实验1和实验2分别考察了全部报告法和部分报告法下身份交换对多身份追踪表现的具体影响。结果均发现, 身份交换对身份−位置绑定干扰程度越大, 位置追踪和身份识别容量也均越低, 但位置容量始终高于身份容量, 并且这些特性在不同追踪负荷上相同。此外, 部分报告法比全部报告法更具有容量测量优势。实验3则进一步从听觉通道上控制了语音复述对当前任务的干扰, 所得结果仍支持实验1和实验2。这表明, 身份交换对多身份追踪的干扰机制是身份−位置绑定机制受到损害, 而非语音复述的作用。     

主动控制感的测量及认知神经机制

主动控制感指预计动作和实际感觉反馈匹配会产生一种控制自己动作、作用于环境的主观体验, 是人类心理活动的基本特征之一。本文系统介绍主动控制感的测量方式, 尤其是主动动作的时间压缩效应这一内隐手段; 并从主观意识、动作的发生方式和动作结果特征三个方面探讨主动控制感的影响因素。基于动作的比较器模型, 解释主动控制感的产生原因; 并提供了主动控制感的认知神经脑机制的证据, 强调额叶和顶叶在主动控制感中的作用。未来研究应该更加注重外显与内隐测量的一致性, 特殊群体以及主动控制感的脑网络研究。     

注意水平对视觉工作记忆客体表征的影响

运用单探测的变化检测范式和注意分配程序,两个实验分别考察了由相同维度特征组成的客体和由不同维度特征组成的客体在工作记忆中的表征方式,以及注意对其的作用。实验1用双色框作为客体,实验2用不同颜色的形状作为客体。被试为27名大学生。结果发现,由相同维度特征组成的客体在工作记忆中只能以单一特征为储存单元,且这种储存不受注意水平的影响,可能是一种自动化的过程;由不同维度特征组成的客体在工作记忆中能以整合形式表征,但是这种表征需要集中性注意的参与。该结果表明,在知觉过程中整合起来的信息在储存到工作记忆的过程中时,仍需要消耗注意资源。     

Semantically induced distortions of visual awareness in a patient with Balint’s syndrome

We present data indicating that visual awareness for a basic perceptual feature (colour) can be influenced by the relation between the feature and the semantic properties of the stimulus. We examined semantic interference from the meaning of a colour word (‘‘RED”) on simple colour (ink related) detection responses in a patient with simultagnosia due to bilateral parietal lesions. We found that colour detection was influenced by the congruency between the meaning of the word and the relevant ink colour, with impaired performance when the word and the colour mismatched (on incongruent trials). This result held even when remote associations between meaning and colour were used (i.e. the word ‘‘PEA” influenced detection of the ink colour red). The results are consistent with a late locus of conscious visual experience that is derived at post-semantic levels. The implications for the understanding of the role of parietal cortex in object binding and visual awareness are discussed.     

The very same thing: Extending the object token concept to incorporate causal constraints on individual identity

The contributions of feature recognition, object categorization, and recollection of episodic memories to the re-identification of a perceived object as the very same thing encountered in a previous perceptual episode are well understood in terms of both cognitive-behavioral phenomenology and neurofunctional implementation. Human beings do not, however, rely solely on features and context to re-identify individuals; in the presence of featural change and similarly-featured distractors, people routinely employ causal constraints to establish object identities. Based on available cognitive and neurofunctional data, the standard object-token based model of individual re-identification is extended to incorporate the construction of unobserved and hence fictive causal histories (FCHs) of observed objects by the pre-motor action planning system. It is suggested that functional deficits in the construction of FCHs are associated with clinical outcomes in both autism spectrum disorders and later-stage stage Alzheimer's disease.     

Is it relevant? Influence of trial manipulations of prospective memory context on task interference

The effects of blocked versus mixed presentation were tested on visual feature binding, assuming that blocked presentation enhances focused attention, whilst mixed presentation recruits extra attentional resources for intratrial as well as intertrial processing. The contextual interference effect suggests that although performance due to mixed presentation is either similar or worse than blocked presentation when tested immediately, it is better when tested after an interval. We explored whether this robust empirical effect, common in psychomotor performance, would be evident in visual feature binding. Stimuli were conjunctions of shape, colour, and location. Study–test intervals from 0 to 2,500 ms were used with a swap detection task. In Experiments 1A and 1B, participants ignored locations to detect shape–colour bindings. In Experiments 2A and 2B, they ignored shapes to detect colour–location binding. In Experiments 3A and 3B, they ignored colours to detect shape–location bindings. Whilst Experiments 1A, 2A, and 3A used blocked presentation, Experiments 1B, 2B, and 3B used mixed presentation of study–test intervals. The results of these experiments and a replication experiment using a within-subjects design showed that the contextual interference effect appeared when spatial attention was engaged, but not when attention was object based.     

Does maintaining bindings in visual working memory require more attention than maintaining features?

ABSTRACT

Whether more attention is required for maintaining bindings than maintaining features in visual working memory (VWM) remains an open question. If maintaining bindings in VWM does not require more attention than maintaining features, is it related to the stability of binding representations? In this study, we explored whether maintaining bindings requires more attention than maintaining features for similar and dissimilar objects by inserting a feature report task into the maintenance phase of VWM in Experiments 1 and 2. We also investigated whether the effect of similarity on the attentional requirement for maintaining bindings and features is due to the stability of VWM representations by inserting a suffix during the maintenance phase of VWM in Experiment 3. The results showed that when object-based attention was consumed, bindings were more impaired than features for dissimilar objects but not for similar objects. We also found that the bindings of similar objects were less interfered by the suffix than those of dissimilar objects. Our findings suggest that maintaining bindings does not require more attention than maintaining features when the binding representations are stable in VWM and similarity improves the stability of binding representations.     

Constrained prose recall and the assessment of long-term forgetting: The case of ageing and the Crimes Test

It has become increasingly clear that some patients with apparently normal memory may subsequently show accelerated long-term forgetting (ALF), with dramatic loss when retested. We describe a constrained prose recall task that attempts to lay the foundations for a test suitable for detecting ALF sensitively and economically. Instead of the usual narrative structure of prose recall tests, it employs a matrix structure involving four episodes, each describing a minor crime, with each crime involving the binding into a coherent episode of a specified range of features, involving the victim, the crime, the criminal and the location, allowing a total of 80 different probed recall questions to be generated. These are used to create four equivalent 20-item tests, three of which are used in the study. After a single verbal presentation, young and elderly participants were tested on three occasions, immediately, and by telephone after a delay of 6 weeks, and at one of a varied range of intermediate points. The groups were approximately matched on immediate test; both showed systematic forgetting which was particularly marked in the elderly. We suggest that constrained prose recall has considerable potential for the study of long-term forgetting.     

Unravelling intention: Distal intentions increase the subjective sense of agency

Experimental studies investigating the contribution of conscious intention to the generation of a sense of agency for one’s own actions tend to rely upon a narrow definition of intention. Often it is operationalized as the conscious sensation of wanting to move right before movement. Existing results and discussion are therefore missing crucial aspects of intentions, namely intention as the conscious sensation of wanting to move in advance of the movement. In the present experiment we used an intentional binding paradigm, in which we distinguished between immediate (proximal) intention, as usually investigated, and longer standing (distal) intention. The results showed that the binding effect was significantly enhanced for distal intentions compared to proximal intentions, indicating that the former leads to stronger sense of agency. Our finding provides empirical support for a crucial distinction between at least two types of intention when addressing the efficacy of conscious intentions.     

Temporal binding during apparent movement of the human body

Alternating between static images of human bodies with an appropriate interstimulus interval (ISI) produces apparent biological motion. Here we investigate links between apparent biological motion and time perception. We presented two pictures of the initial and final positions of a human movement separated by six different ISIs. The shortest movement path between two positions was always biomechanically impossible. Participants performed two tasks: In an explicit task, participants judged whether they saw the longer, feasible movement path between the two postures, or the shorter, biomechanically impossible path. In an implicit task, participants judged the duration of a white square surrounding the picture sequence. At longer ISIs participants were more likely to see a longer, feasible movement path (explicit task) and underestimated the duration of body picture pairs, compared to trials displaying degraded body pictures (implicit task). We argue that perceiving apparent biological motion involves temporal binding of two static pictures into a continuous movement. Such temporal binding may be mediated by a top-down mechanism that produces a percept of biological motion in the absence of any retinal motion.