Effects of cognitive load presence and duration on driver eye movements and event detection performance

This study examined the effects of cognitive load on driving performance for interactions with an in-vehicle information system (IVIS) that varied in duration from 1 to 4 min. Twelve participants drove in a simulator while intermittently performing the IVIS task. There were three IVIS conditions: interacting with the IVIS, non-IVIS periods between IVIS interactions, and baseline driving without the IVIS task. Contrary to our hypothesis, driver response to lead vehicle braking was surprisingly uniform across IVIS conditions. IVIS interaction did undermine driver ability to detect the bicyclist along the side of the road, and some of these performance decrements persisted after the IVIS interaction had ended. Reaction time for bicyclist detection increased from the first to the subsequent minutes of the interaction. Eye movements were influenced by the IVIS conditions but not by task duration. Both ANOVA and factor analyses revealed that some of the changes in eye movements were concurrent with IVIS interaction while others persisted after the driver completed the IVIS interaction. Overall, the findings suggest that two mechanisms might account for the distraction-related performance decrements in this study: competition for processing resources and interference due to activation of competing goals.     

Ultra-rapid categorisation in non-human primates

The visual system of primates is remarkably efficient for analysing information about objects present in complex natural scenes. Recent work has demonstrated that they perform this at very high speeds. In a choice saccade task, human subjects can initiate a first reliable saccadic eye movement response to a target (the image containing an animal) in only 120 ms after image onset. Such fast responses impose severe time constraints if one considers neuronal responses latencies in high-level ventral areas of the macaque monkey. The question then arises: are non-human primates able to perform the task? Two rhesus macaque monkeys (Macaca mulatta) were trained to perform the same forced-choice categorization task as the one used in humans. Both animals performed the task with a high accuracy and generalized to new stimuli that were introduced everyday: accuracy levels were comparable both with new and well-known images (84% vs. 94%). More importantly, reaction times were extremely fast (minimum reaction time 100 ms and median reaction time 152 ms). Given that typical single units onset times in Inferotemporal cortex (IT) are about as long as the shortest behavioural responses measured here, we conclude that visual processing involved in ultra rapid categorisations might be based on rather simple shape cue analysis that can be achieved in areas such as extrastriate cortical area V4. The present paper demonstrates for the first time, that rhesus macaque monkeys (Macaca mulatta) are able to match human performance in a forced-choice saccadic categorisation task of animals in natural scenes.     

Do fish count? Spontaneous discrimination of quantity in female mosquitofish

The spontaneous tendency to join the largest social group was used to investigate quantity discrimination in fish. Fish discriminated between shoals that differed by one element when the paired numbers were 1vs2, 2vs3 and 3vs4, but not when 4vs5 or larger. Using large numerosities (>4), the ability to discriminate between two numbers improved as the numerical distance between them increased and a significant discrimination was found only with ratios of 1:2 or smaller (4vs8, 8vs16 and 4vs10). Experiments to control for non-numerical variables evidenced the role played by the total area of stimuli with both large and small numerosities; the total quantity of movement of the fish within a shoal appeared also important but only when large numerosities were involved. Even though the pattern of discrimination exhibited by female mosquitofish is not fully consistent with any of the existing models of quantity representation, our results seem to suggest two distinct mechanisms in fish, one used to compare small numbers of objects and one used when larger numerosities are involved.     

学习时间分配机制的眼动研究

本研究采用被试内的实验设计,以无意义词对为实验材料,利用眼动记录技术,通过分析在有无时间压力时,个体对不同难度词对的学习时间分配,检验学习时间分配的差距缩减模型和最近学习区模型.研究发现:(1)在总注视时间上,难度和时间压力的影响都是显著的,并且存在交互作用.(2)个体的学习次序是由易到难的.研究结果支持了最近学习区模型.     

How status and stereotypes impact attributions to discrimination: The stereotype-asymmetry hypothesis

Past research suggests a status-asymmetry effect in attributions to discrimination such that people are more likely to make attributions to discrimination when the victim is from a lower status group than the perpetrator as compared to when the victim is from a higher status group than the perpetrator. The present studies test a stereotype-asymmetry effect, such that people are more likely to make attributions to discrimination when rejection occurs in a domain in which the victim is negatively rather than positively stereotyped. In Study 1 (observers) and Study 2 (victims), participants attributed rejection following a job interview to discrimination more when the victim was negatively stereotyped than when the victim was positively stereotyped. The stereotypicality of the domain was more important than the relative status of the victim and the perpetrator in determining judgments of discrimination. Thus stereotype-asymmetry is a key feature of the discrimination prototype.     

Formation of partially and fully elaborated generalized equivalence classes

Most complex categories observed in real-world settings consist of perceptually disparate stimuli, such as a picture of a person's face, the person's name as written, and the same name as heard, as well as dimensional variants of some or all of these stimuli. The stimuli function as members of a single partially or fully elaborated generalized equivalence class when they occasion the mutual selection of each other after the establishment of some subset of relations among the stimuli. Indeed, it is these generalized relations among stimuli that enable an individual to respond appropriately to the inevitable flux of natural environments. The present experiments involved procedures for producing both types of generalized equivalence class and for evaluating their retention. Granting the formal and functional similarities that exist between generalized equivalence classes and natural categories, natural kinds, and fuzzy superordinate classes, the variables responsible for the emergence of the former might also account for the emergence of the latter three phenomena. In Experiment 1, After forming an A'-B' class, a B'-C relation was trained and generalization tests were conducted with B'-C, C-B', A'-C, and C'-A. Two of 5 participants passed the tests documenting the formation of A'-B'-C classes. Failures occurred in the A'-C and C-A' tests but not the B'-C and C-B' tests. Failures were also correlated with time between A'-B' class formation and C-based testing and with the absence of baseline confirmation when training and testing were separated by about one week. Experiment 2 replicated Experiment 1 but presented baseline confirmation probes immediatley prior to testing when training and testing were separated by one week; all participants then formed partially elaborated generalized equivalence classes. In Experiment 3, 5 of 6 participants formed fully elaborated generalized equivalence classes, represented as A' = B' = C'.     

SENSITIVITY OF CONDITIONAL-DISCRIMINATION PERFORMANCE TO WITHIN-SESSION VARIATION OF REINFORCER FREQUENCY

The present experiment developed a methodology for assessing sensitivity of conditional-discrimination performance to within-session variation of reinforcer frequency. Four pigeons responded under a multiple schedule of matching-to-sample components in which the ratio of reinforcers for correct S₁ and S₂ responses was varied across components within session. Initially, five components, each arranging a different reinforcer-frequency ratio (from 19 to 91), were presented randomly within a session. Under this condition, sensitivity to reinforcer frequency was low. Sensitivity failed to improve after extended exposure to this condition, and under a condition in which only three reinforcer-frequency ratios were varied within session. In a later condition, three reinforcer-frequency ratios were varied within session, but the reinforcer-frequency ratio in effect was differentially signaled within each component. Under this condition, values of sensitivity were similar to those traditionally obtained when reinforcer-frequency ratios for correct responses are varied across conditions. The effects of signaled vs. unsignaled reinforcer-frequency ratios were replicated in two subsequent conditions. The present procedure could provide a practical alternative to parametric variation of reinforcer frequency across conditions and may be useful in characterizing the effects of a variety of manipulations on steady-state sensitivity to reinforcer frequency.     

Future Thinking in Young Children

ABSTRACT— The study of future thinking is gaining momentum across various domains of psychology. Mentally projecting the self forward in time (i.e., mental time travel) is argued to be uniquely human and of vital importance to the evolution of human culture. Yet it is only recently that developmentalists have begun to study when, and how, this capacity emerges. I begin by outlining the concept of mental time travel, along with newly developed methodologies to test children's ability to mentally project the self into the future. Data suggest that this ability is in place by ages 4 or 5 but also reveal conditions under which children may experience difficulty accurately predicting their future desires. I conclude by discussing how the research on children's mental time travel can be used to further our understanding of the development of future-oriented behaviors, including planning and delaying gratification.     

大学生特质焦虑与网络成瘾的关系:一个有调节的中介模型

通过对530名大学生的问卷调查,考察特质焦虑、压力知觉、未来时间洞察力和网络成瘾之间的关系。结果发现：（1）压力知觉在特质焦虑和网络成瘾之间起部分中介作用,特质焦虑既对网络成瘾产生直接影响,也通过压力知觉产生间接影响;（2）未来时间洞察力对压力知觉的中介作用起调节作用,压力知觉对网络成瘾的影响随着个体未来时间洞察力的增加而减少。大学生特质焦虑、压力知觉、未来时间洞察力和网络成瘾共同构成一个有调节的中介模型。     

基于价值的议程对学习时间分配影响的眼动研究

通过对比不同梯度下, 分值激发的议程与习惯性反应作用一致、不一致条件中, 优先选择项目和学习时间的差异, 考察基于价值的议程对学习时间分配的影响及其动态过程。结果发现：(1)等分值条件下, 汉语为母语被试存在从左到右的习惯性反应。(2)分值梯度对基于议程的学习时间分配的有效性具有调节作用。小分值梯度(1分、5分)激发的议程能够克服习惯性反应对学习时间分配的影响, 但不能使被试建立起优先学习高价值项目的议程; 大分值梯度(1分、10分)能够克服习惯性反应对学习时间分配影响, 且能够使被试建立起优先学习高价值项目的议程。(3)基于议程调节的学习时间分配在时程和阶段上具有动态性和情境特异性。