语言加工过程中的视听跨通道整合

日常生活中, 语言的使用往往出现在某个视觉情境里。大量认知科学研究表明, 视觉信息与语言信息加工模块并不是独立工作, 而是存在复杂的交互作用。本文以视觉信息对语言加工的影响为主线, 首先对视觉信息影响言语理解, 言语产生以及言语交流的相关研究进展进行了综述。其次, 重点对视觉信息影响语言加工的机制进行了探讨。最后介绍了关于视觉信息影响语言加工的计算模型, 并对未来的研究方向提出了展望。     

视觉工作记忆的巩固加工：时程、模式及机制

在视觉工作记忆加工过程中, 对记忆项目的维持及操作需要将转瞬即逝的感觉输入转换为稳定的记忆表征, 这一加工过程被定义为视觉工作记忆巩固。鉴于巩固在视觉工作记忆中所起到的“门控”作用, 研究者们已经发展出多种研究范式对其可能涉及的运作机制进行探讨。然而, 在不同范式下所观察到的巩固时程存在较大差异, 其所遵循的巩固模式也尚不清晰。此外, 对于巩固所涉及的理论及神经机制亦存在不同的观点。通过对比不同范式的差异性及梳理各方的观点, 可以有效推动这些问题的解决。未来研究除了可以在多种范式下对巩固模式进行验证, 还可以探究注意在巩固中的作用, 以及项目熟悉性等因素会对巩固加工产生何种影响。     

Unique contribution of semantic representations to immediate memory: an individual-differences approach

Studies have reported dissociations between the contributions of semantic and phonological representations to immediate remembering, found through experimental manipulations as well as specific clinical cases. Also, some studies based on the analysis of individual differences reported that a semantic cued recall task has a variance unshared with the immediate memory tasks which tap the contribution of phonological representations. However, another study suggested that cued recall performance could reflect a wider ability to cluster information by category. Furthermore, no studies of individual differences have investigated the unique semantic contribution in the visual domain. Therefore, the present study used specific immediate recognition memory tasks that have been used to investigate the semantic contribution in the verbal and visual domains. The results demonstrate the unshared variance that reflects the semantic contribution in both the verbal and the visual domain, and some commonality in these variances across the domains.     

On the examination couch: the relationship between the egocentric perspective and the attentional focus

Determined by anatomical characteristics, the binocular visual field has an elliptical shape. Whereas the focus of attention – that area of the visual field in which objects can be consciously perceived – is significantly smaller, its shape is not necessarily dependent on the same factors. Indeed, it is yet unknown if the maximum extents of the attentional focus’ meridians are dimensionally stable or adapt to the egocentric perspective. In this study, we intended to measure the expansion up to which peripheral stimuli can still be perceived while participants were sitting and lying on the left and on the right body side. Results demonstrate that contrary to the visual field the maximum extents along the attentional focus’ meridians remain stable across different head positions with a greater horizontal than vertical alignment. This indicates that the expansion ratios of the meridians of the attentional focus are not dependent on the egocentric perspective. Rather, they appear stable in space and gravity-based. Findings are discussed in terms of our visual environment and current as well as alternative interpretations are weighed against each other.     

Face processing is enhanced in the left and upper visual hemi-fields

We tested whether two known hemi-field asymmetries would affect visual search with face stimuli. Holistic processing of spatial configurations is better in the left hemi-field, reflecting a right hemisphere specialization, and object recognition is better in the upper visual field, reflecting stronger projections into the ventral stream. Faces tap into holistic processing and object recognition at the same time, which predicts better performance in the left and upper hemi-field, respectively. In the first experiment, participants had to detect a face with a gaze direction different from the remaining faces. Participants were faster to respond when targets were presented in the left and upper hemi-field. The same pattern of results was observed when only the eye region was presented. In the second experiment, we turned the faces upside-down, which eliminated the typical spatial configuration of faces. The left hemi-field advantage disappeared, showing that it is related to holistic processing of faces, whereas the upper hemi-field advantage related to object recognition persisted. Finally, we made the search task easier by asking observers to search for a face with open among closed eyes or vice versa. The easy search task eliminated the need for complex object recognition and, accordingly, the advantage of the upper visual field disappeared. Similarly, the left hemi-field advantage was attenuated. In sum, our findings show that both horizontal and vertical asymmetries affect the search for faces and can be selectively suppressed by changing characteristics of the stimuli.     

Semantic and visual relatedness of distractors impairs episodic retrieval of pictures in a divided attention paradigm

We used a divided attention (DA) paradigm to infer the representational codes needed to support episodic retrieval of pictures, by measuring susceptibility to memory interference from different distracting tasks. Participants made recognition memory decisions to semantically categorized sets of pictures while simultaneously making size judgments to a set of visually-presented distractor pictures. Recognition accuracy was worse and response times were slower under DA conditions relative to full attention (FA), regardless of semantic relatedness of distractors to targets (Experiment 1). Similarly, we found no differential memory interference under DA relative to FA when distractor pictures were either visually (but not semantically), semantically (but not visually), or unrelated to the targets (Experiment 2). In Experiment 3, memory interference was significantly larger under DA at retrieval when distractors were both semantically and visually similar to the targets. Findings suggest episodic memory for pictures requires access to either visually- or semantically-based representations for optimal performance.     

Psychological,social and physical environmental mediators of the SCORES intervention on physical activity among children living in low-income communities

ObjectivesThis study examined mediation effects of socio-ecological variables on accelerometer-determined physical activity among children in the Supporting Children's Outcomes using Rewards, Exercise and Skills (SCORES) intervention.DesignRandomized control trial mediation analysis.MethodsPrimary school children were randomly assigned the SCORES multi-component intervention or control group for the 12-month study. The outcome was accelerometer derived total moderate-to-vigorous physical activity (MVPA). Hypothesized mediators measured in children were physical activity enjoyment and perceived sport competence and social support. Hypothesized mediators measured in parents were family social support, access to physical activity facilities and equipment at home, and perceived access to physical activity opportunities in the local community. Mediation analyses were conducted using multi-level linear analysis in MPlus.ResultsThere were significant intervention effects for social support from teachers (A = 1.73, SE = 0.88, p = 0.048) and parental perceived access to physical opportunities in the local community (A = 2.69, SE = 1.12, p = 0.016). There were significant associations between changes in perceived sport competence (B = 0.48, SE = 0.36, p = 0.027), parental perceived access to physical activity opportunities in the local community (B = 0.60, SE = 0.26, p = 0.021), and changes in total MVPA. Parental perceived access to physical activity opportunities in the local community was found to have a significant mediating effect on total MVPA (AB = 1.61, 95% CI = 0.06 to 3.95, proportion 13%).ConclusionsParental perceived access to physical activity opportunities in the local community is a potential mechanism of behavior change for children and mediated the effect of the SCORES intervention on objectively measured physical activity.     

工作记忆对知觉类别学习的影响:问题与构想

人们学习将感知到的客体按照不同的标准或规则分类存储,即类别学习。而工作记忆作为多种认知加工的基础,对类别学习具有重要作用。基于已有研究,分别梳理了言语工作记忆和视空工作记忆对基于规则和信息整合类别结构的影响。目前,执行功能是否影响内隐类别学习系统、工作记忆负荷对内隐外显类别学习系统的影响是否一致还存在争议。此外,工作记忆影响知觉类别学习的认知加工阶段尚不清晰。未来的研究还需明确工作记忆负荷对内隐和外显类别学习的影响,进一步验证工作记忆影响类别学习的认知加工阶段假设的合理性。     

视觉注意离散性的实验范式

注意离散性是注意间歇性地采集外界信息的特性。文章综述了视觉注意离散性的4种实验范式:(1)车轮错觉范式,刺激强度大、实验条件少、被试任务量小,较早地证实了视觉注意的离散性;(2)视觉探测范式,同时观察了被试的行为表现与电生理信号,确定了视觉注意离散性与神经振荡的关联;(3)线索靶子范式和视觉搜索范式,通过系统地变化SOA大幅提高了行为数据的时间分辨率,直观地探测到注意离散性调制的行为振荡。     

学习方法对陌生语言字形学习的影响

采用学习——测查的范式,以陌生视觉单词(韩字)为材料,考察了学习方法对陌生语言字形学习效果的影响。在学习阶段,材料分别以连续重复(集中学习)和间隔重复(分散学习)方式呈现6遍,在学习之后半小时、1天以及1个星期之后,分别进行再认记忆测查。结果发现,虽然随着测查间隔时间的增长,两种学习条件的成绩都显著降低,但是在三次测查中,分散学习的成绩都明显好于集中学习。这一结果说明在排除语音、语义等其他言语元素的干扰之后,以分散学习的方式学习新字形的效果好于集中学习。