Concurrent generalization gradients for food-controlled and shock-controlied behavior

In the presence of a bright light, monkeys were trained to press a lever to avoid shock and to pull a chain for food reward. After gradients of generalization to other light intensities had been determined for each response, gradients were subsequently secured after training in a brightness discrimination and under several free-shock conditions. The following results were obtained: (1) Generalization gradients prior to discrimination training were much steeper for the food-controlled response than for the shock-controlled response. This finding was confirmed in another study in which rats served as subjects. (2) After discrimination training, both gradients became much steeper, but the avoidance gradient still showed more generalized responding than that of reward. (3) After a period of continuous testing with all the different test intensities, the two gradients became even steeper. In addition, differences between the two gradients virtually disappeared. (4) The intermittent delivery of free shocks during a previously non-shocked light intensity radically affected the shape of the avoidance gradient, just as the addition of an avoidance contingency did during the same, previously non-shocked, light intensity.     

Personality factors of individuals who survive traumatic experiences without professional help

This is a study of the personality resources that enable certain individuals to cope successfully with traumatic experiences without planned psychotherapeutic intervention. A survey of 40 trauma-surviving respondents reveals some common positive developmental and psychosocial factors. Also, five cases are described who experienced serious trauma, three of them living successful lives and two remaining disabled. The biological predisposition and the specific interaction of ones nature and nurture leading toward resolution of traumatic experiences are discussed. Individuals who have survived Posttraumatic Stress Disorder should be studied further within a psychobiological framework.     

Distributed Connectionist Models in Social Psychology

Distributed connectionist models of mental representation (also termed PDP or parallel distributed processing, or ANN or artificial neural networks) constitute a fundamental alternative to the associative or schematic models that have been much more prevalent in social psychology. A connectionist model is made up of a large number of very simple processing units, richly interconnected and able to send signals to each other depending on their momentary activation levels. No individual processing unit represents a meaningful concept; instead, overall patterns of activation hold representational meaning. This article emphasizes the novel properties of connectionist representation that might appeal to theorists and researchers in social psychology, including their context sensitivity and flexibility, ability to represent prototypes and exemplars within a single network, and ability to determine whether a stimulus is familiar even before the stimulus can be identified or categorized.     

Conflict monitoring and feature overlap: Two sources of sequential modulations

Recent findings demonstrating that the Simon effect diminishes when the preceding trial is a noncorresponding trial led researchers to develop two alternative accounts. The conflict monitoring account argues that the automatic activation from stimulus location information is under the regulation of a control mechanism, which adjusts the level of activation depending on conflict in the preceding trial. In contrast, the feature integration account holds that sequential modulations of the Simon effect can be attributed to the integration of stimulus and response features into event files. Previous research demonstrated a potential contribution to sequential modulations from both mechanisms. We use a four-choice task to extend these findings and to investigate the exact nature of the feature overlap effects. Both conflict monitoring and feature overlap effects were found to contribute to sequential modulations. However, the feature overlap effects did not conform to predictions of the feature integration account. We argue that the feature overlap effects are accounted for better by strategic shortcuts in response selection.     

Situated Social Cognition

ABSTRACT— Social cognition refers to the mental representations and processes that underlie social judgments and behavior—for example, the application of stereotypes to members of social groups. Theories of social cognition have generally assumed that mental representations are abstract and stable and that they are activated and applied by relatively automatic, context-independent processes. Recent evidence is inconsistent with these expectations, however. Social-cognitive processes have been shown to be adaptive to the perceiver's current social goals, communicative contexts, and bodily states. Although these findings can often be given ad hoc explanations within current conceptual frameworks, they invite a fuller integration with the broad intellectual movement emphasizing situated cognition. Such an approach has already been influential in many areas within psychology and beyond, and theories in the field of social cognition would benefit by taking advantage of its insights.     

Development of an Everyday Spatial Behavioral Questionnaire

The authors developed a 12-category, 116-item critical incident questionnaire of spatial behavior. The authors administered the Everyday Spatial Behavioral Questionnaire (ESBQ) to volunteer undergraduates (114 women, and 31 men) and tests of spatial ability to establish both the reliability and construct validity of the instrument. The authors found that Cronbach's alpha across the subscale scores was .92, and that 8 of the 12 subscales had alphas of .70 or greater. The authors found validity of the ESBQ through canonical correlation analysis. Specifically, spatial tests, gender, and age variables, jointly with the ESBQ subscales, identified 2 apparent continua of spatial skills. The authors labeled the first continuum movement through space (from moving a vehicle at one end of the continuum, to moving one's own body through space at the other end of the continuum). The authors labeled the second identified continuum drawing/perceiving perspective/path finding, and it appeared to represent a continuum of 3-dimensional visualization or redirection. Another suggested label was dimensional discernment. Thus, the ESBQ is a first step toward identifying new ways to think about and quantify people's spatial experience.     

Self-Driving Cars and Engineering Ethics: The Need for a System Level Analysis

Science and Engineering Ethics - The literature on self-driving cars and ethics continues to grow. Yet much of it focuses on ethical complexities emerging from an individual vehicle. That is an...     

Comparing the effects of positive and negative feedback in information-integration category learning

Categorical learning is dependent on feedback. Here, we compare how positive and negative feedback affect information-integration (II) category learning. Ashby and O’Brien (2007) demonstrated that both positive and negative feedback are required to solve II category problems when feedback was not guaranteed on each trial, and reported no differences between positive-only and negative-only feedback in terms of their effectiveness. We followed up on these findings and conducted 3 experiments in which participants completed 2,400 II categorization trials across three days under 1 of 3 conditions: positive feedback only (PFB), negative feedback only (NFB), or both types of feedback (CP; control partial). An adaptive algorithm controlled the amount of feedback given to each group so that feedback was nearly equated. Using different feedback control procedures, Experiments 1 and 2 demonstrated that participants in the NFB and CP group were able to engage II learning strategies, whereas the PFB group was not. Additionally, the NFB group was able to achieve significantly higher accuracy than the PFB group by Day 3. Experiment 3 revealed that these differences remained even when we equated the information received on feedback trials. Thus, negative feedback appears significantly more effective for learning II category structures. This suggests that the human implicit learning system may be capable of learning in the absence of positive feedback.     

Separating the effect of reward from corrective feedback during learning in patients with Parkinson’s disease

Parkinson’s disease (PD) is associated with procedural learning deficits. Nonetheless, studies have demonstrated that reward-related learning is comparable between patients with PD and controls (Bódi et al., Brain, 132(9), 2385–2395, 2009; Frank, Seeberger, & O’Reilly, Science, 306(5703), 1940–1943, 2004; Palminteri et al., Proceedings of the National Academy of Sciences of the United States of America, 106(45), 19179–19184, 2009). However, because these studies do not separate the effect of reward from the effect of practice, it is difficult to determine whether the effect of reward on learning is distinct from the effect of corrective feedback on learning. Thus, it is unknown whether these group differences in learning are due to reward processing or learning in general. Here, we compared the performance of medicated PD patients to demographically matched healthy controls (HCs) on a task where the effect of reward can be examined separately from the effect of practice. We found that patients with PD showed significantly less reward-related learning improvements compared to HCs. In addition, stronger learning of rewarded associations over unrewarded associations was significantly correlated with smaller skin-conductance responses for HCs but not PD patients. These results demonstrate that when separating the effect of reward from the effect of corrective feedback, PD patients do not benefit from reward.