Stimulus aspects of aversive controls: the effects of response contingent shock

A tone ending with electrical shock was periodically presented to pigeons while they pecked a key for food. Pairs of birds were run simultaneously under a yoked program which insured that both birds received the same number and temporal distribution of shocks. For one of the birds, shock was always initiated by a peck; for the other, shock was unavoidable. Both procedures led to reduced rates of pecking in the presence of the tone, and gradients of stimulus generalization were obtained. But the effects of response contingent shock extinguished more rapidly than the effects of unavoidable shock. In general, birds exposed to unavoidable shock tended to respond at intermediate rates throughout tone, whereas those exposed to response contingent shock ceased to peck for part or all of the tone period.     

阅读障碍的巨细胞系统缺陷理论之争

近几年诸多研究者认为阅读障碍是由于视觉系统巨细胞功能缺陷引起的。他们从对比度敏感性研究、巨细胞抑制功能研究与视觉运动知觉功能的研究结果中得到了支持证据。就这个问题的研究进行综述,表明不论是巨细胞功能缺陷理论的支持者还是反对者,都从巨细胞的对比度敏感性、视觉运动知觉与巨细胞抑制功能上得到了一些研究结果的支持。巨细胞功能缺陷理论的支持者还从阅读障碍的神经生理学研究和阅读的脑功能研究中得到了一些支持性的证据。新的研究结果揭示了巨细胞系统缺陷理论与阅读之间的关系以及巨细胞系统缺陷理论的应用价值。在巨细胞系统缺陷理论的进一步研究中,还需要统一实验方法与实验标准以获得更多的证据,同时需要有新的方法来有效区分小细胞系统与巨细胞系统     

Market entry decisions: effects of absolute and relative confidence

In a market entry game, the number of entrants usually approaches game-theoretic equilibrium quickly, but in real-world markets business start-ups typically exceed market capacity, resulting in chronically high failure rates and suboptimal industry profits. Excessive entry has been attributed to overconfidence arising when expected payoffs depend partly on skill. In an experimental test of this hypothesis, 96 participants played 24 rounds of a market entry game, with expected payoffs dependent partly on skill on half the rounds, after their confidence was manipulated and measured. The results provide direct support for the hypothesis that high levels of confidence are largely responsible for excessive entry, and they suggest that absolute confidence, independent of interpersonal comparison, rather than confidence about one's abilities relative to others, drives excessive entry decisions when skill is involved.     

The influence of CS-US interval on several different indices of learning in appetitive conditioning

Four experiments examined the effects of varying the conditioned stimulus-unconditioned stimulus (CS-US) interval (and US density) on learning in an appetitive magazine approach task with rats. Learning was assessed with conditioned response (CR) measures, as well as measures of sensory-specific stimulus-outcome associations (Pavlovian-instrumental transfer, potentiated feeding, and US devaluation). The results from these studies indicate that there exists an inverse relation between CS-US interval and magazine approach CRs, but that sensory-specific stimulus-outcome associations are established over a wide range of relatively long, but not short, CS-US intervals. These data suggest that simple CR measures provide different information about what is learned than measures of the specific stimulus-outcome association, and that time is a more critical variable for the former than latter component of learning.     

Social Identity and Social Exchange: Identification, Support, and Withdrawal From the Job

Integrating insights from the social exchange perspective and the social identity perspective, we propose that evaluations of support received from the organization and its representatives and organizational identification interact to predict withdrawal from the job. The relationship of support with withdrawal is proposed to be weaker the more strongly employees identify with the organization. This prediction was confirmed in 2 samples focusing on different operationalizations of support and withdrawal. Study 1 explored the interaction between organizational support and organizational identification in predicting turnover intention; Study 2 investigated the link between supervisor support and organizational identification and absenteeism. The present study thus yields evidence that may lay the groundwork for further integration of social exchange and social identity analyses of organizational behavior.     

General and Domain-Specific Self-Esteem Among Regular Education and Special Education Students

We examined the global and domain-specific self-esteem of students who are emotionally disturbed, students who are learning disabled, and students who are in regular education classrooms. Students who were emotionally disturbed or learning disabled had lower global self-esteem than did students in regular education classes. The specific domains in which students in special education felt that they were less competent than students in regular education included social skills, leadership skills, and academics. However, the 2 groups of students in special education did not differ from one another. No differences emerged between the groups on a measure of self-esteem that is less subject to social desirability concerns. Implications of this research for education are discussed.     

Evolutionary perspective on indirect victimization in adolescence: the role of attractiveness, dating and sexual behavior

We studied indirect victimization from an evolutionary perspective by examining links between this type of victimization and several indicators of attractiveness (past sexual behavior, dating frequency and physical appearance). Two thousand three hundred and nineteen (56% female) students (ages 13-18) from a region of southern Ontario, Canada, completed self-report measures of indirect victimization, physical appearance, dating frequency, recent sexual behavior (number of partners in previous month) and past sexual behavior (number of lifetime partners minus number of partners in previous month) as well as indexes of depression, aggression and attachment security, which were used to control for psychosocial maladjustment. Consistent with an evolutionary framework, physical appearance interacted significantly with gender, wherein attractive females were at greater risk for indirect victimization, whereas for males physical attractiveness was a protective factor, reducing risk of victimization. Physical appearance also interacted with grade, being inversely related to indirect victimization for younger adolescents and having a nonsignificant association with victimization for older youth. Finally, recent sexual behavior was associated with increased risk of indirect victimization for older adolescents only, which we discussed with regard to peer perceptions of promiscuity and short-term mating strategies. These findings have important implications for the development of interventions designed to reduce peer victimization, in that victims of indirect aggression may represent a rather broad, heterogeneous group, including attractive individuals with no obvious signs of maladjustment.     

Producing and Recognizing Analogical Relations

Analogical reasoning is an important component of intelligent behavior, and a key test of any approach to human language and cognition. Only a limited amount of empirical work has been conducted from a behavior analytic point of view, most of that within Relational Frame Theory (RFT), which views analogy as a matter of deriving relations among relations. The present series of four studies expands previous work by exploring the applicability of this model of analogy to topography-based rather than merely selection-based responses and by extending the work into additional relations, including nonsymmetrical ones. In each of the four studies participants pretrained in contextual control over nonarbitrary stimulus relations of sameness and opposition, or of sameness, smaller than, and larger than, learned arbitrary stimulus relations in the presence of these relational cues and derived analogies involving directly trained relations and derived relations of mutual and combinatorial entailment, measured using a variety of productive and selection-based measures. In Experiment 1 participants successfully recognized analogies among stimulus networks containing same and opposite relations; in Experiment 2 analogy was successfully used to extend derived relations to pairs of novel stimuli; in Experiment 3 the procedure used in Experiment 1 was extended to nonsymmetrical comparative relations; in Experiment 4 the procedure used in Experiment 2 was extended to nonsymmetrical comparative relations. Although not every participant showed the effects predicted, overall the procedures occasioned relational responses consistent with an RFT account that have not yet been demonstrated in a behavior-analytic laboratory setting, including productive responding on the basis of analogies.