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.     

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。     

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.     

The role of Theory of Mind in assessing cooperative intentions

Folk wisdom indicates that people vary in the extent to which they can assess others’ cooperative intentions. In two studies we investigated whether Theory of Mind (ToM), the ability to represent mental states of others, is related to accuracy in the recognition of cooperativeness. Participants completed a ToM task and were asked to assess either video clips of people playing a variation of a Prisoner’s Dilemma (PD) game (Study 1, N = 88), or photographs of people playing PD taken at the very moment when they were expressing a decision to cooperate or to defect (Study 2, N = 99). We found relationships between ToM and cooperative intention recognition only in Study 1, when participants were exposed to long versions of the video clips. In contrast to previous reports, participants in our samples did not score higher than chance in cooperativeness assessment except for Study 1 in the condition with short video clips. Our results question human expertise at identifying defectors and cooperators and do not provide clear support for an association between ToM and cooperativeness assessment. The findings are discussed from the perspective of an evolutionary arms race between interpreting and masking cooperative intentions.     

Data-driven sequence learning or search: What are the prerequisites for the generation of explicit sequence knowledge?

In incidental sequence learning situations, there is often a number of participants who can report the task-inherent sequential regularity after training. Two kinds of mechanisms for the generation of this explicit knowledge have been proposed in the literature. First, a sequence representation may become explicit when its strength reaches a certain level (Cleeremans, 2006), and secondly, explicit knowledge may emerge as the result of a search process that is triggered by unexpected events that occur during task processing and require an explanation (the unexpected-event hypothesis; Haider & Frensch, 2009). Our study aimed at systematically exploring the contribution of both mechanisms to the generation of explicit sequence knowledge in an incidental learning situation. We varied the amount of specific sequence training and inserted unexpected events into a 6-choice serial reaction time task. Results support the unexpected-event view, as the generation of explicit sequence knowledge could not be predicted by the representation strength acquired through implicit sequence learning. Rather sequence detection turned out to be more likely when participants were shifted to the fixed repeating sequence after training than when practicing one and the same fixed sequence without interruption. The behavioral effects of representation strength appear to be related to the effectiveness of unexpected changes in performance as triggers of a controlled search.     

Using an Example Statement Increases Information but Does Not Increase Accuracy of CBCA,RM, and SCAN

Verbal credibility assessment methods are frequently used in the criminal justice system to investigate the truthfulness of statements. Three of these methods are Criteria Based Content Analysis (CBCA), Reality Monitoring (RM), and Scientific Content Analysis (SCAN). The aim of this study is twofold. First, we investigated the diagnostic accuracy of CBCA, RM, and especially SCAN. Second, we tested whether giving the interviewee an example of a detailed statement can enhance the diagnostic accuracy of these verbal credibility methods. To test the latter, two groups of participants were requested to write down one true and one fabricated statement about a negative event. Prior to this request, one group received a detailed example statement, whereas the other group received no additional information. Results showed that CBCA and RM scores differed between true and fabricated statements, whereas SCAN scores did not. Giving a detailed example statement did not lead to better discrimination between truth tellers and liars for any of the methods but did lead to the participants producing significantly longer statements. The implications of these findings are discussed. Copyright © 2013 John Wiley & Sons, Ltd.     

Does interaction matter? Testing whether a confidence heuristic can replace interaction in collective decision-making

In a range of contexts, individuals arrive at collective decisions by sharing confidence in their judgements. This tendency to evaluate the reliability of information by the confidence with which it is expressed has been termed the ‘confidence heuristic’. We tested two ways of implementing the confidence heuristic in the context of a collective perceptual decision-making task: either directly, by opting for the judgement made with higher confidence, or indirectly, by opting for the faster judgement, exploiting an inverse correlation between confidence and reaction time. We found that the success of these heuristics depends on how similar individuals are in terms of the reliability of their judgements and, more importantly, that for dissimilar individuals such heuristics are dramatically inferior to interaction. Interaction allows individuals to alleviate, but not fully resolve, differences in the reliability of their judgements. We discuss the implications of these findings for models of confidence and collective decision-making.