Object representations are biased toward each other through statistical learning

The visual system is remarkably efficient at extracting regularities from the environment through statistical learning. While such extraction has extensive consequences on cognition, it is unclear how statistical learning shapes the representations of the individual objects that comprise the regularities. Here we examine how statistical learning alters object representations. In three experiments, participants were exposed to either random arrays containing objects in a random order, or structured arrays containing object pairs where two objects appeared next to each other in fixed spatial or temporal configurations. After exposure, one object in each pair was briefly presented and participants judged the location or the orientation of the object without seeing the other object in the pair. We found that when an object reliably appeared next to another object in space, it was judged as being closer to the other object in space even though the other object was never presented (Experiments 1 and 2). Likewise, when an object reliably preceded another object in time, its orientation was biased toward the orientation of the other object even though the other object was never presented (Experiment 3). These results demonstrated that statistical learning fundamentally shapes how individual objects are represented in visual memory, by biasing the representation of one object toward its co-occurring partner. Importantly, participants in all experiments were not explicitly aware of the regularities. Thus, the bias in object representations was implicit. The current study reveals a novel impact of statistical learning on object representation: spatially co-occurring objects are represented as being closer in space, and temporally co-occurring objects are represented as having more similar features.     

Nostalgia and Temporal Life Satisfaction

Recent research has shown that nostalgia, an apparently past-oriented emotion, may render the present self more positive and promote a brighter outlook on the future. The current study examined whether experimentally induced nostalgia would impact the levels of and associations among past, present, and future life satisfaction. Among 250 university students (86 males and 164 females, aged 16–26 years), nostalgia was manipulated through the recollection of nostalgic (vs. ordinary) events. In support of our hypotheses, the results showed that nostalgic experiences not only led to a larger contrast between past life satisfaction versus present and future life satisfaction, but also weaker associations between past and future life satisfaction and between present and future life satisfaction. Overall, the findings suggest that nostalgic experiences can render more distinct judgements on temporal life satisfaction.     

Parental Involvement in Primary School Education: its Relationship with Children’s Academic Performance and Psychosocial Competence through Engaging Children with School

The benefits of parental involvement in children’s education have been well established but increasing evidence suggests that overparenting may have adverse effects on children. The question of whether excessive parental involvement hinders children’s academic and psychosocial development warrants further investigations. This study examined the associations of parental educational involvement at home and in school with academic performance and psychological health of 507 Chinese Grade 3 schoolchildren in Hong Kong. Parents reported on their level of involvement in children’s schooling and their children’s psychosocial issues. Children were surveyed to determine their school engagement, and their Chinese language and mathematics attainment was assessed. We also explored the underlying mechanism by testing children’s engagement with school as a mediator of the relationships. Our results showed that home-based parental educational involvement was positively associated with children’s language competence and psychosocial wellbeing, and the associations were linked through engaging children with school. However, the benefits reached a plateau at higher level of parental involvement in children’s learning at home. School-based parental involvement had an indirect effect on children’s prosocial behavior through school engagement. These findings highlight the significance of optimal level of parental involvement in children’s education at home for children’s development.     

Both Earlier Times and the Future Are “Front”: The Distinction Between Time‐ and Ego‐Reference‐Points in Mandarin Speakers’ Temporal Representation

Mandarin speakers, like most other language speakers around the world, use spatial terms to talk about time. However, the direction of their mental temporal representation along the front‐back axis remains controversial because they use the spatial term “front” to refer to both earlier times (e.g., front‐year means “the year before last”) and the future (e.g., front‐road means “prospect”). Although the linguistic distinction between time‐ and ego‐reference‐point spatiotemporal metaphors in Mandarin suggests a promising clarification of the above controversy, there is little empirical evidence verifying this distinction. In this study, Mandarin speakers’ time‐ and ego‐reference‐point temporal representations on three axes (i.e., sagittal, lateral, and vertical) were separately examined through two tasks. In a time‐reference‐point task, Mandarin speakers judged whether the time point of the second picture was earlier or later than the time point of the first picture, while in an ego‐reference‐point task, they judged whether an event or phase had happened in the past or would happen in the future. The results indicate that Mandarin speakers construe an earlier‐times‐in‐front‐of‐later‐times temporal sequence and adopt the front‐to‐the‐future orientation.     

No advantage for remembering horizontal over vertical spatial locations learned from a single viewpoint

Previous behavioral and neurophysiological research has shown better memory for horizontal than for vertical locations. In these studies, participants navigated toward these locations. In the present study we investigated whether the orientation of the spatial plane per se was responsible for this difference. We thus had participants learn locations visually from a single perspective and retrieve them from multiple viewpoints. In three experiments, participants studied colored tags on a horizontally or vertically oriented board within a virtual room and recalled these locations with different layout orientations (Exp. 1) or from different room-based perspectives (Exps. 2 and 3). All experiments revealed evidence for equal recall performance in horizontal and vertical memory. In addition, the patterns for recall from different test orientations were rather similar. Consequently, our results suggest that memory is qualitatively similar for both vertical and horizontal two-dimensional locations, given that these locations are learned from a single viewpoint. Thus, prior differences in spatial memory may have originated from the structure of the space or the fact that participants navigated through it. Additionally, the strong performance advantages for perspective shifts (Exps. 2 and 3) relative to layout rotations (Exp. 1) suggest that configurational judgments are not only based on memory of the relations between target objects, but also encompass the relations between target objects and the surrounding room—for example, in the form of a memorized view.     

反应抑制的训练:内容、效果与机制

近期的研究发现,个体的反应抑制能力具有一定的可塑性。研究者多采用双盲随机对照实验设计,训练的对象包括儿童、成人和特殊群体,研究者通过Go/Nogo、Stop-signal等任务进行为期1周至3周,45至7200试次不等的抑制控制能力训练,并结合行为、脑电以及脑成像等技术对训练效果进行评估,研究结果发现,接受了抑制控制训练的个体其抑制能力得到提升,并伴随脑神经活动的变化。另外,研究者发现,抑制控制能力的训练效果还可以迁移至个体日常生活中的表现。但是,也有些研究并未发现抑制控制训练的效果。训练任务的设置,评估任务的选择以及被试反应策略的差异等因素可能会影响训练的效果。抑制控制训练引发行为与大脑活动的变化可能是由于训练导致了个体建立了自上而下有意识的抑制控制模式和自下而上的自动抑制模式。反应抑制和冲突抑制可塑性的比较,儿童与老年人抑制功能的训练以及训练效果的追踪研究将成为该领域日后研究的重点问题。     

“集体主义—个体主义”的差异:来自基因、大脑的证据

文章以"集体主义—个体主义"这一基本文化差异维度为基础,围绕文化、基因和大脑之间的关系,介绍了国内外最新研究进展。研究显示当人类执行各种文化任务时,那些为人类生存提供有力帮助的基因会被选择和保留下来;在自我表征,注意和知觉,决策、情绪和意向推断等心理状态或过程上的"集体主义—个体主义"文化差异都可追溯到脑功能的差异。研究者先后提出社会脑假设、文化—基因协同进化论、神经—文化交互作用模型等理论来解释基因、文化与大脑交互作用的现象。文章分析了当前研究中存在的问题,并对未来的研究进行了展望。     

Modeling of 1-3 piezoelectric composites operating in thickness-stretch vibration mode

For bulk piezoelectric ceramics plates, the fundamental thickness-stretch (TSt) waves are always coupled to the in-plane extension waves and the symmetric thickness-shear waves. The occurrence of these spurious modes in bulk piezoelectric ceramics plates is undesirable as it may interfere with the operation of transducers. 1–3 piezoelectric composites are promising candidates to suppress the spurious modes mentioned above. However, theoretical modelling of multiphase ceramic composite objects is very complex. In this study, a simple analytical TSt vibration model is constructed from three-dimensional equations of linear piezoelectricity. The mechanical damping is considered in the model by introducing a complex elastic constant. The performance of 1–3 piezoelectric composites is analysed and the electrical impedance results from theoretical and experimental analysis are compared. The results show that there is excellent agreement between the experimental electrical impedance and that obtained by the theoretical TSt vibration analysis. This indicates that 1–3 piezoelectric composites can be operated in a nearly pure TSt vibration mode near the fundamental resonance. The analytical model we present is valid for analysing 1–3 piezoelectric composites plates with large aspect ratios quickly and efficiently.