不同搜索情境下老化对自上而下注意加工的影响

在视觉搜索过程中,老年人是否可以在不同情境下调节自上而下和自下而上的加工水平尚不明确。为了探讨老化对认知灵活性的影响,研究采用空间线索范式,通过比较有效线索和无效线索来考察对线索的注意加工水平（注意捕获、注意抑制）,通过比较目标相关和目标无关线索的注意加工水平来考察自上而下和自下而上的作用,通过改变分心物一致性来调控不同的目标凸显情境。结果发现,年轻组在目标非凸显时的空间线索效应高于目标凸显时,表明年轻人会依据目标凸显性调整自上而下的加工水平;但老年组却没有产生这种差异,其更依赖自上而下的加工,注意系统会对目标相关的线索进行注意捕获,对目标无关的线索进行注意抑制。结果表明,随着年龄的增长,认知控制的灵活性下降,表现出对自上而下加工较多的依赖;此外,老年人依然保留着注意捕获和注意抑制的能力,这对认知老化中抑制能力受损的观点提出了挑战。     

Consciously monitored grasping is vulnerable to perceptual intrusions

The idea of functional differentiation between vision-for-action and vision-for-perception has been supported by evidence from different domains. According to this account, perception is based on consciously accessible, relative representations, whereas vision-for-action is performed in an analytic, automatic manner. Support for this idea comes from studies that showed that unlike perception, grasping movements are refractory to illusions and to Weber’s law. Yet, interactions between the systems may occur when an action is performed in a less automated fashion. To test this idea, we asked participants to monitor their fingers apertures in flight and to halt their movement for a short duration when they felt that their aperture reached a maximum amount. The results showed that movements in the monitored condition were biased by the Ponzo illusion and showed atypical adherence to Weber's law. These results show that action and perception are more likely to interact when movements are performed in a controlled manner.     

Friends in Low-Entropy Places: Orthographic Neighbor Effects on Visual Word Identification Differ Across Letter Positions

Visual word recognition is facilitated by the presence of orthographic neighbors that mismatch the target word by a single letter substitution. However, researchers typically do not consider where neighbors mismatch the target. In light of evidence that some letter positions are more informative than others, we investigate whether the influence of orthographic neighbors differs across letter positions. To do so, we quantify the number of enemies at each letter position (how many neighbors mismatch the target word at that position). Analyses of reaction time data from a visual word naming task indicate that the influence of enemies differs across letter positions, with the negative impacts of enemies being most pronounced at letter positions where readers have low prior uncertainty about which letters they will encounter (i.e., positions with low entropy). To understand the computational mechanisms that give rise to such positional entropy effects, we introduce a new computational model, VOISeR (Visual Orthographic Input Serial Reader), which receives orthographic inputs in parallel and produces an over-time sequence of phonemes as output. VOISeR produces a similar pattern of results as in the human data, suggesting that positional entropy effects may emerge even when letters are not sampled serially. Finally, we demonstrate that these effects also emerge in human subjects' data from a lexical decision task, illustrating the generalizability of positional entropy effects across visual word recognition paradigms. Taken together, such work suggests that research into orthographic neighbor effects in visual word recognition should also consider differences between letter positions.     

Holistic processing of faces is intact in adults with autism spectrum disorder

Are face recognition difficulties in Autism Spectrum Disorders (ASD) related to impaired holistic processing? Gauthier et al. [Gauthier, I., Klaiman, C., &; Schultz, R. T. (2009). Face composite effects reveal abnormal face processing in Autism spectrum disorders. Vision Research, 49, 470–478. doi:10.1016/j.visres.2008.12.007] used the face composite task in adolescents with autism and found a congruency effect that was not modulated by alignment, a result which was interpreted as reflecting qualitatively different face processing mechanisms. In the present study we tested adults with ASD in a composite face task where presentation times were manipulated and further explored whether these participants were sensitive to holistic information in faces using a new version of the composite task: VHFPT 2.0 (The Vanderbilt Holistic Face Processing Test 2.0). Results suggest that adults with ASD process faces holistically and that their facial identity processing abilities are qualitatively similar and as efficient as that of typical adults. The difference between the results of Gauthier et al. (2009) with adolescents and the results with adults here reported are interpreted in terms of a developmental delay.     

Driving speed choice: The role of conscious monitoring and control (reinvestment) when driving

This study aimed to examine the role of reinvestment - the propensity to consciously monitor and control actions (movement specific reinvestment) and to consciously monitor and evaluate decision making processes (Decision specific reinvestment) while driving in everyday risky scenarios. The study also aimed to evaluate the association between reinvestment and previously validated driver attitude measures. Fifty one participants completed a series of questionnaires (Driving Self-Efficacy Scale, Driver Attitude Questionnaire, Movement Specific Reinvestment Scale, Decision Specific Reinvestment Scale) after which they completed a test phase in a driving simulator. In the test phase, driving scenarios included roads with different markings (i.e., double yellow, wide centrelines, wire rope barriers, Audio Tactile Profiled markings) and alerting scenarios (i.e., police car present, high crash risk area sign, reduced speed zone). Results revealed that on risky roads (wide centrelines), participants with a high propensity for decision specific reinvestment drove slower than those with a low propensity. Driver experience, attitudes towards speeding and scores on the Decision Reinvestment subscale of the Decision Specific Reinvestment Scale significantly predicted speed choice. More experienced participants with higher scores on the Decision Reinvestment subscale were more likely to drive slower and participants with worse attitudes towards speeding were likely to drive faster. Participants with a low propensity for movement specific reinvestment (specifically, Movement Self-Consciousness) reduced their speed to a greater extent than those with a high propensity when driving in the police car scenario. There was some evidence to suggest that high decision specific and movement specific reinvesters were more likely to be involved in crashes and receive driving infringements. The current study is the first to demonstrate a significant relationship between reinvestment and driving. The implications of these findings for road safety are discussed.     

A medical records managing and securing blockchain based system supported by a Genetic Algorithm and Discrete Wavelet Transform

The privacy of patients is jeopardised when medical records and data are spread or shared beyond the protected cloud of institutions. This is because breaches force them to the brink that they start abstaining from full disclosure of their condition. This type of condition has a negative effect on scientific research, patients and all stakeholders. A blockchain-based data sharing system is proposed to tackle this issue, which employs immutability and autonomy properties of the blockchain to sufficiently resolve challenges associated with access control and handle sensitive data. Our proposed system is supported by a Discrete Wavelet Transform to enhance the overall security, and a Genetic Algorithm technique to optimise the queuing optimization technique as well. Introducing this cryptographic key generator enhances the immunity and system access control, which allows verifying users securely in a fast way. This design allows further accountability since all users involved are already known and the blockchain records a log of their actions. Only when the users’ cryptographic keys and identities are confirmed, the system allows requesting data from the shared queuing requests. The achieved execution time per node, confirmation time per node and robust index for block number of 0.19 s, 0.17 s and 20 respectively that based on system evaluation illustrates that our system is robust, efficient, immune and scalable.     

Metaphorical sense-making: visual-narrative language portraits of South African students

This article reflects on a creative visual-narrative approach to understanding South African students’ lived experiences of languages. Data were collected in two interviews: the first entailing a biographical history and the drawing of a linguistic portrait on a simple body outline and the second a narrative interview utilising the portrait generated in the first as a basis for talking about language and identity. Framing the research process in this creative visual mode shifts the focus of narrative talk, simultaneously grounding it in affective, embodied experience, and enabling a reflexive position from which to analyse the taken-for-granted role of language in the minutiae of everyday life. The theoretical lenses of identity and subjectivity are invigorated through these metaphorical representations, and new creative possibilities are released for analysing the role of language in mediating shifting power dynamics in post-apartheid and postcolonial South African life.     

发展性计算障碍儿童的数量转换缺陷

本研究拟考察发展性计算障碍儿童的认知缺陷成因。实验1要求被试在三种形式(点/点,数/数,点/数)下进行数量比较,实验2仅将点集替换为汉字数字词。结果表明障碍组和正常组在数/数、点/数和汉字/汉字比较任务上的成绩存在显著差异,而在点/点和汉字/汉字比较上没有差异。据此推论,计算障碍儿童符号加工能力受到损伤,符号与非符号数量转换能力存在缺陷,但非符号加工能力和不同符号间数量转换没有缺陷,支持语义提取缺陷假设。