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Philosophical Studies -     

Delayed imitation of complex behavioural sequences by 14- to 16-month olds

The present study was conducted to determine if children under the age of 18 months can exhibit delayed imitation of three-event sequences when they have no opportunity to practice. Twenty-three 14- to 16-month-old children underwent two different imitation conditions. In the practice condition the children could imitate the sequence immediately after modelling; then they were tested 1 or 7 days later. In the no practice condition the children had the chance to imitate only on the test day. Children were able to imitate the sequences under both conditions irrespective of the delay period. They produced significantly more target actions, and more target actions in the correct order, in the test phase and cued recall phase, compared with the baseline. There were no differences between the two conditions with a 1-day delay period, but after a 7-day delay, the number of target actions produced during the practice condition was significantly higher than those in the no practice condition. The results are discussed in terms of nonverbal mimetic representations. © 1998 John Wiley & Sons, Ltd.     

Comparing positive and negative patterning in human learning

In human causal learning, positive patterning (PP) and negative patterning (NP) discriminations are often acquired at roughly the same rate, whereas PP is learned faster than NP in most experiments with nonhuman animals. One likely reason for this discrepancy is that most causal learning scenarios encourage participants to treat the presentation and omission of the relevant outcome as two events of comparable significance and likelihood. To investigate this, the current experiments compared PP and NP using a predictive learning paradigm based on a mock gambling task. In Experiment 1, one outcome (winning) was made more salient by being less frequent than the alternative outcome (losing). Under these circumstances, PP was learned faster than NP. In Experiment 2, subjects learned two PP and two NP discriminations, one involved win versus no change outcomes, the other involved lose versus no change outcomes. The subjects learned PP faster than NP, but only when discriminating win from no change. We argue that a difference in difficulty between PP and NP relies on a difference in the salience of the outcomes, consistent with the predictions of a relatively simple model of associative learning.     

Motion influences gaze direction discrimination and disambiguates contradictory luminance cues

In two experiments, we investigated the role of apparent motion in discriminating left/right gaze deviation judgments. We demonstrated that discrimination accuracy and response confidence was significantly higher when the eyes were moved to the left or right, compared to when the eyes were presented in their final shifted position (static images). To dissociate the role of motion signals from luminance signals, gaze stimuli were also presented in reverse contrast. Replicating past studies polarity reversal had a profound and detrimental effect on gaze discrimination in static images, although, intriguingly, while response confidence remained low, participant performance improved as gaze angle increased. In striking contrast to these data, polarity reversal had no negative effect on performance when the eyes were moved. We discuss these findings in the context of a multiple-cue account of gaze perception.     

判断与决策研究纵观:基于模糊痕迹理论的视角(英文)

模糊痕迹理论是用于解释记忆、判断与决策的综合性理论,该理论的提出和发展主要基于对信息存储、表征、提取和加工过程的研究。本文首先介绍了模糊痕迹理论的基本原则,在此基础上重点讨论了其要义(gist)如何发挥核心作用,使得模糊痕迹理论有别于其他传统的决策模型。该理论将高级直觉与原始冲动性进行了区分,并且预测决策误差来源于判断与决策的各种不同成分,如背景知识、信息表征、提取和加工过程等。模糊痕迹理论不仅可以解释诸如框架效应、合取谬误等传统决策与判断文献中常讨论的误差现象,同时基于该理论的研究还得到了一些与传统决策理论相悖的新发现。此外,对脑与行为如何发育性变化的研究为我们了解成人的认知过程提供了至关重要的新视角,这些对脑与行为的发育性研究和对特殊人群的研究结果也都支持了模糊痕迹理论对要义加工依赖的预测。