Short-term memory across eye blinks

The effect of eye blinks on short-term memory was examined in two experiments. On each trial, participants viewed an initial display of coloured, oriented lines, then after a retention interval they viewed a test display that was either identical or different by one feature. Participants kept their eyes open throughout the retention interval on some blocks of trials, whereas on others they made a single eye blink. Accuracy was measured as a function of the number of items in the display to determine the capacity of short-term memory on blink and no-blink trials. In separate blocks of trials participants were instructed to remember colour only, orientation only, or both colour and orientation. Eye blinks reduced short-term memory capacity by approximately 0.6–0.8 items for both feature and conjunction stimuli. A third, control, experiment showed that a button press during the retention interval had no effect on short-term memory capacity, indicating that the effect of an eye blink was not due to general motoric dual-task interference. Eye blinks might instead reduce short-term memory capacity by interfering with attention-based rehearsal processes.     

Hierarchical single- and dual-process models of recognition memory

Recognition memory is commonly modeled as either a single, continuous process within the theory of signal detection, or with two-process models such as Yonelinas’ dual-process model. Previous attempts to determine which model provides a better account of the data have relied on fitting the models to data that are averaged over items. Because such averaging distorts conclusions, we develop and compare hierarchical versions of competing single and dual-process models that account for item variability. The dual-process model provides a superior account of a typical data set when models are compared with the deviance information criterion. Parameters of the dual-process model are highly correlated, however, suggesting that a single-process model may exist that can provide a better account of the data.     

Adaptive criterion setting in perceptual decision making

Pigeons responded in a perceptual categorization task with six different stimuli (shades of gray), three of which were to be classified as "light" or "dark", respectively. Reinforcement probability for correct responses was varied from 0.2 to 0.6 across blocks of sessions and was unequal for correct light and dark responses. Introduction of a new reinforcement contingency resulted in a biphasic process of adjustment: First, choices were strongly biased towards the favored alternative, which was followed by a shift of preference back towards unbiased choice allocation. The data are well described by a signal detection model in which adjustment to a change in reinforcement contingency is modeled as the change of a criterion along a decision axis with fixed stimulus distributions. Moreover, the model shows that pigeons, after an initial overadjustment, distribute their responses almost optimally, although the overall benefit from doing so is extremely small. The strong and swift effect of minute changes in overall reinforcement probability precludes a choice strategy directly maximizing expected value, contrary to the assumption of signal detection theory. Instead, the rapid adjustments observed can be explained by a model in which reinforcement probabilities for each action, contingent on perceived stimulus intensity, determine choice allocation.     

A detection model of college withdrawal

Many students during their college careers consider withdrawing from their respective college or university. Understanding why some students decide to withdraw yet others persist has implications for both the well being of students as well as for institutes of higher education. The present study develops a model of the decision to withdraw drawing on theories of voluntary employee turnover from organizational psychology and signal detection theory from the cognitive sciences. The model posits that precipitating events or shocks (e.g., changes in tuition) lead students to consider withdrawing from the university. If the evidence surpasses a criterion then the student decides to withdraw. The model was used to identify shocks students were sensitive to and to test hypotheses about the underlying decision process. The theoretical implications of this model in terms of understanding and predicting student withdrawal decisions and voluntary employee turnover decisions are discussed.     

7～10岁自闭症谱系障碍儿童对情绪面孔的觉察与加工

为了考察自闭症谱系障碍(autism spectrum disorder,ASD)儿童对不同情绪面孔的觉察和加工情况,设计两个眼动实验任务,要求14名7～10岁ASD儿童和20名同年龄正常儿童观看图片。实验一采用将情绪面孔嵌入风景图片中引起语义不一致的刺激;实验二采用含有情绪面孔的无意义背景乱序图片刺激。结果发现:(1)ASD儿童对不同情绪面孔的觉察时间都显著长于正常儿童;(2)与正常儿童一样,ASD儿童表现出对恐惧面孔的注意偏向;(3)实验二中,ASD儿童对不同情绪面孔内部特征区的注意分配与正常儿童不同;正常儿童能注意最能展示该类情绪特征信息的区域,如恐惧的眼睛、愉快的嘴巴,而ASD儿童对三类情绪面孔特征区的注意分配方式相似;(4)两个实验条件下,ASD者对不同情绪面孔的觉察、加工模式与正常儿童相似。     

Spatial updating according to a fixed reference direction of a briefly viewed layout

Three experiments examined the role of reference directions in spatial updating. Participants briefly viewed an array of five objects. A non-egocentric reference direction was primed by placing a stick under two objects in the array at the time of learning. After a short interval, participants detected which object had been moved at a novel view that was caused by table rotation or by their own locomotion. The stick was removed at test. The results showed that detection of position change was better when an object not on the stick was moved than when an object on the stick was moved. Furthermore change detection was better in the observer locomotion condition than in the table rotation condition only when an object on the stick was moved but not when an object not on the stick was moved. These results indicated that when the reference direction was not accurately indicated in the test scene, detection of position change was impaired but this impairment was less in the observer locomotion condition. These results suggest that people not only represent objects’ locations with respect to a fixed reference direction but also represent and update their orientation according to the same reference direction, which can be used to recover the accurate reference direction and facilitate detection of position change when no accurate reference direction is presented in the test scene.     

Driving without awareness: The effects of practice and automaticity on attention and driving

This research examined the development of proceduralised “driving without awareness” in a driving simulator by paying participants to drive a simulated road regularly over 12 weeks of testing. This longitudinal research paradigm is a significant departure from previous studies which have examined drivers in a conscious attentional mode using short experimental sessions or cross-sectional designs comparing expert and novice performance. During each session, participants took two “trips” on the simulated road; sometimes travelling on a “to and from” journey on one half of the road, sometimes traversing the entire road in one direction. A range of measures, including driving performance, vehicle detection, perceptual speed regulation, and hazard reactions were collected. The results showed the development of driving patterns and changes in object detection performance indicative of proceduralised driving. Speed and lane position variability quickly decreased with practice, as did participants’ subjective experiences of driving difficulty. Performance on an embedded detection task appeared to become a proceduralised part of the driving task, becoming highly efficient in later stages of the experiment. The changes in attentional focus and driving performance over time provide new light on previous research findings and allow us to critically re-examine several established models of driver behaviour.     

Need for Cognition and the process of lie detection

Four experiments investigated the influence of Need for Cognition on the process of lie detection. According to the basic assumptions of dual process models, only higher Need for Cognition leads to the use of verbal information when making judgments of veracity. People with lower Need for Cognition predominantly use stereotypical nonverbal information for their judgments. In both Experiments 1 and 2, participants saw a film in which nonverbal cues (fidgety vs. calm movements) and verbal cues (low vs. high plausibility) were manipulated. As predicted, when Need for Cognition was lower, only the nonverbal cues influenced participants' judgments of veracity. In contrast, participants with higher Need for Cognition also used the verbal cues. Experiments 3 and 4 tested the hypothesis that higher Need for Cognition leads to better discrimination of truthful from deceptive messages. Both experiments found that participants with higher Need for Cognition achieved higher accuracy at classifying truthful and deceptive messages than participants with lower Need for Cognition.     

变化盲视的最新研究进展

变化盲视指观察者不能探测到客体或情境中的变化 ,是近十年以来认知心理学的研究热点之一。变化盲视可发生在各种实验条件下。例如 ,在扫视、眨眼、电影镜头切换时发生的变化以及真实情景的交互作用中发生的变化 ,观察者都有可能探测不到。本文介绍了近年来对于变化盲视的研究成果 ,包括经常使用的实验范式和对这个现象的解释等