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21.
The gradedness or discreteness of our visual awareness has been debated. Here, we investigate the influence of spatial scope of attention on the gradedness of visual awareness. We manipulated scope of attention using hierarchical letter-based tasks (global: broad scope; local: narrow scope). Participants reported the identity of a masked hierarchical letter either at the global level or at the local level. We measured subjective awareness using the perceptual awareness scale ratings and objective performance. The results indicate more graded visual awareness (lesser slope for the awareness rating curve) at the global level compared to the local level. Graded perception was also observed in visibility ratings usage with global level task showing higher usage of the middle PAS ratings. Our results are in line with the prediction of level of processing hypothesis and show that global/local attentional scope and contextual endogenous factors influence the graded nature of our visual awareness.  相似文献   
22.
PurposeThe current study examined the impact on children’s street crossing behaviors of not having auditory-based information about traffic when crossing streets.MethodUsing a fully-immersive virtual reality system, numerous indices of children’s street crossing behaviors were measured both when they had auditory-based information about traffic and when this was lacking.ResultsThe lack of traffic sounds did not influence the inter-vehicle gap size that children crossed into but it did result in slower initiations and, ultimately, more high-risk outcomes (close calls and hits).ConclusionTraffic sounds significantly contribute to enhance children’s safety when crossing streets. Cars with reduced sounds (e.g., electric) and anything that interferes with children accessing auditory-based traffic information (e.g., wearing headphones) could increase their risk of pedestrian injury.  相似文献   
23.
A variable message sign (VMS), which is a key component of intelligent transportation systems, has been frequently used in the management of urban roads and motorways to provide drivers with real-time traffic condition information about a road section or area. Nevertheless, there is a lack of unified regulations for VMS design, which makes it difficult to accurately determine the understandability and legibility of VMS information. In practice, inappropriate designs of VMSs are common, such as overload of VMS information and excessive number of phases, particularly on the urban roads of China. Building on our earlier findings obtained by surveys, in this study, field tests were conducted to assess the reliability of VMS information in terms of the visual perception characteristics of drivers. For a full visual perception, the information displayed on a VMS must be reliable, i.e., it should be easy for drivers to detect, obtain, and understand the messages they require. Two basic theories—information theory and visual perception theory—were introduced to build a quantification model of VMS information, select evaluation indices, and design the experimental process. A total of 24 drivers participated in the field experiments and questionnaires. Five indices—information obtainment rate, periodic validity, driver subjective scoring and the corresponding UI (represents information intelligibility), and CE (represents information legibility)—were analyzed to evaluate their relationships to VMS information reliability. The results confirmed that the amount of information, and the scrolling period considering redundant distance, significantly affect the reliability of VMSs information. For static VMSs, the information obtainment rate and the subjective scoring decrease with increasing amount of information. The recollection accuracy of the drivers significantly declines when the amount of information shown increases to 90 bits, corresponding to an information obtainment rate of less than 0.8 and UI equal to 0. For dynamic VMSs, the information reliability deteriorates as the scrolling period shortens and the number of phases increases. Unreasonable reliability is found when the periodic validity is less than 0.9, i.e., the actual scrolling period is more than 10% less than the calculated one, corresponding to CE equal to 0. The reliability of information was evaluated by combining the subjective scoring of the drivers and a data-based statistical analysis and considering driving safety. Accordingly, it was recommended that 90 bit is the maximum amount of information to be shown on a VMS and that the preferred scrolling period of each phase of a dynamic VMS is 5 s. The results of this study support the objective of providing reliable information to drivers by addressing the problems related to the amount of information and presentation time for VMSs. These findings provide a basis for determining the thresholds for VMS information to promote practical and user-friendly designs of VMSs on urban roads.  相似文献   
24.
Under numerous circumstances, humans recognize visual objects in their environment with remarkable response times and accuracy. Existing artificial visual object recognition systems have not yet surpassed human vision, especially in its universality of application. We argue that modeling the recognition process in an exclusive feedforward manner hinders those systems’ performance. To bridge that performance gap between them and human vision, we present a brief review of neuroscientific data, which suggests that considering an agent’s internal influences (from cognitive systems that peripherally interact with visual-perceptual processes) recognition can be improved. Then, we propose a model for visual object recognition which uses these systems’ information, such as affection, for generating expectation to prime the object recognition system, thus reducing its execution times. Later, an implementation of the model is described. Finally, we present and discuss an experiment and its results.  相似文献   
25.
词汇识别与记忆受到词汇之间语义联想关系的影响。鉴于自由联想方法建立词汇语义联想关系的局限性, 研究者们提出用共现联想法建立词汇之间的语义联想关系。本文对词汇共现频率视角下的语义联想效应及其神经机制的研究进行分析发现, 语义联想的丰富程度和关联程度影响词汇的加工; 与少语义联想词相比, 多语义联想词导致P200波幅增大和N400波幅减小; 语义联想加工涉及的脑区主要是额上回和左内侧颞叶区域。未来研究需要探讨自由联想法和共现联想法建立语义联想关系的差异, 基于共现联想法进一步地探究语义联想的行为规律和神经机制, 并从共现联想的角度开展汉语语义联想效应及神经机制的研究。  相似文献   
26.
相似性对视觉工作记忆表征的促进被称为相似性效应。以相似项目间的距离和是否插入其他项目改变邻近性,并操纵记忆项空间构型有序性,探讨邻近性对相似性效应的影响。结果发现,不同空间构型和邻近性条件下相似项目的记忆正确率高于非相似项目;在空间构型有序下,相似项目距离远时,插入其他项目时的相似性效应值低于不插入,而空间构型无序下未发现显著差异。这表明相似性促进视觉工作记忆表征,空间构型在邻近性对相似性效应的影响中起重要作用。  相似文献   
27.
This investigation examined whether impairment in configural processing could explain deficits in face emotion recognition in people with Parkinson’s disease (PD). Stimuli from the Radboud Faces Database were used to compare recognition of four negative emotion expressions by older adults with PD (n = 16) and matched controls (n = 17). Participants were tasked with categorizing emotional expressions from upright and inverted whole faces and facial composites; it is difficult to derive configural information from these two types of stimuli so featural processing should play a larger than usual role in accurate recognition of emotional expressions. We found that the PD group were impaired relative to controls in recognizing anger, disgust and fearful expressions in upright faces. Then, consistent with a configural processing deficit, participants with PD showed no composite effect when attempting to identify facial expressions of anger, disgust and fear. A face inversion effect, however, was observed in the performance of all participants in both the whole faces and facial composites tasks. These findings can be explained in terms of a configural processing deficit if it is assumed that the disruption caused by facial composites was specific to configural processing, whereas inversion reduced performance by making it difficult to derive both featural and configural information from faces.  相似文献   
28.
Memory for affective events plays an important role in determining people’s behavior and well-being. Its determinants are far from being completely understood. We investigated how recognition memory for affective pictures depends on pictures’ motivational significance (valence and arousal), complexity (figure-ground compositions vs. scenes), and social content (pictures with people vs. without people) and on observers’ age and gender. Younger, middle-aged, and older adults viewed 84 pictures depicting real-life situations. After a break, the participants viewed 72 pictures, half of which had been viewed previously and half of which were novel, and were asked to endorse whether each picture was novel or had been presented previously. Hits, false alarms, and overall performance (discrimination accuracy) were our dependent variables. The main findings were that, across participants, recognition memory was better for unpleasant than pleasant pictures and for pictures depicting people than pictures without people. Low-arousal pictures were more accurately recognized than high-arousal pictures, and this effect was significantly larger among middle-aged and older adults than younger adults. Recognition memory worsened across adulthood, and this decline was steeper among men than women. Middle-aged and older women outperformed their male counterparts. This study suggests that how well we are able to successfully discriminate previously seen pictorial stimuli from novel stimuli depends on several pictures’ properties related to their motivational significance and content, and on observer’s age and gender.  相似文献   
29.
汉字识别和听写是字词水平上两项重要的读写技能。对127名一年级儿童进行了两年4个时间点的追踪调查, 通过测查儿童的一般认知能力、语音意识、正字法意识和语素意识(包括同音语素意识、复合语素意识), 探讨影响儿童汉字识别和听写发展的因素。利用潜变量增长模型, 结果发现:(1)汉字识别呈线性发展趋势, 听写呈先快后慢的非线性发展趋势, 二者均存在补偿效应; (2)语素意识显著预测了汉字识别的起始水平和发展速度, 但语素意识对听写的起始水平和发展速度均不具有显著的预测作用。研究结果表明儿童入学初始的汉字识别和听写水平并不决定后期的发展速度; 语素意识对儿童汉字识别和听写发展的作用不同。  相似文献   
30.
Despite the lack of invariance problem (the many-to-many mapping between acoustics and percepts), human listeners experience phonetic constancy and typically perceive what a speaker intends. Most models of human speech recognition (HSR) have side-stepped this problem, working with abstract, idealized inputs and deferring the challenge of working with real speech. In contrast, carefully engineered deep learning networks allow robust, real-world automatic speech recognition (ASR). However, the complexities of deep learning architectures and training regimens make it difficult to use them to provide direct insights into mechanisms that may support HSR. In this brief article, we report preliminary results from a two-layer network that borrows one element from ASR, long short-term memory nodes, which provide dynamic memory for a range of temporal spans. This allows the model to learn to map real speech from multiple talkers to semantic targets with high accuracy, with human-like timecourse of lexical access and phonological competition. Internal representations emerge that resemble phonetically organized responses in human superior temporal gyrus, suggesting that the model develops a distributed phonological code despite no explicit training on phonetic or phonemic targets. The ability to work with real speech is a major advance for cognitive models of HSR.  相似文献   
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