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Philosophical Studies -     

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。     

Secondary traumatic stress in emergency medicine clinicians

Previously called Secondary Traumatic Stress (STS), secondary exposure to trauma is now considered a valid DSM-5 Criterion A stressor for posttraumatic stress disorder (PTSD). Previous studies have found high rates of STS in clinicians who treat traumatically injured patients. However, little research has examined STS among Emergency Medicine (EM) physicians and advanced practice providers (APPs). The current study enrolled EM providers (N = 118) working in one of 10 hospitals to examine risk factors, protective factors, and the prevalence of STS in this understudied population. Most of the participants were physicians (72.9%), Caucasian (85.6%), and male (70.3%) with mean age of 39.7 (SD = 8.9). Overall, 12.7% of the sample screened positive for STS with clinical levels of intrusion, arousal, and avoidance symptom clusters, and 33.9% had at least one symptom cluster at clinical levels. Low resilience and a history of personal trauma were positively associated with positive STS screens and STS severity scores. Borderline significance suggested that female gender and spending ≥10% of one’s time with trauma patients could be additional risk factors. Findings suggest that resilience-building interventions may be beneficial.