DISCRIMINATION ACQUISITION IN CHILDREN WITH DEVELOPMENTAL DISABILITIES UNDER IMMEDIATE AND DELAYED REINFORCEMENT

We evaluated the discrimination acquisition of individuals with developmental disabilities under immediate and delayed reinforcement. In Experiment 1, discrimination between two alternatives was examined when reinforcement was immediate or delayed by 20 s, 30 s, or 40 s. In Experiment 2, discrimination between 2 alternatives was compared across an immediate reinforcement condition and a delayed reinforcement condition in which subjects could respond during the delay. In Experiment 3, discrimination among 4 alternatives was compared across immediate and delayed reinforcement. In Experiment 4, discrimination between 2 alternatives was examined when reinforcement was immediate and 0‐s or 30‐s intertrial intervals (ITI) were programmed. For most subjects, discrimination acquisition occurred under immediate reinforcement. However, for some subjects, introducing delays slowed or prevented discrimination acquisition under some conditions. Results from Experiment 4 suggest that longer ITIs cannot account for the lack of discrimination under delayed reinforcement.     

Perceptions of personal sex discrimination: the role of belief in a just world and situational ambiguity

The roles of belief in a just world (BJW) and discrimination against ones' group in perceptions of personal discrimination were examined. Female participants (n = 63) were personally discriminated against in a laboratory setting. We manipulated whether the experimenter appeared to discriminate against other participants, which presumably made the presence of personal discrimination less ambiguous, or did not appear to discriminate against others, which presumably made personal discrimination more ambiguous. In the no group discrimination condition, but not in the group discrimination condition, participants' perceptions of being personally discriminated against depended on individual differences in BJW: Women with a strong BJW perceived less personal discrimination than those with a weak BJW. Also, strong BJW women in the group discrimination condition perceived less personal discrimination than strong BJW women in the no group discrimination condition.     

Perceived Discrimination and Health-Related Quality of Life: Testing the Reserve Capacity Model in Hispanic Americans

ABSTRACT

This study tested aspects of the Reserve Capacity Model (Gallo & Matthews, 2003 Gallo, L. C. and Matthews, K. A. 2003. Understanding the association between socioeconomic status and physical health: Do negative emotions play a role?. Psychological Bulletin, 129: 10–51. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]; Gallo, Penedo Espinosa de los Monteros, & Arguelles, 2009 Gallo, L. C., Penedo, F. J., Espinosa de los Monteros, K. and Arguelles, W. 2009. Resiliency in the face of disadvantage: Do Hispanic cultural characteristics protect health outcomes?. Journal of Personality, 77: 1707–1746. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) as a means of understanding disparities in health-related quality of life appraisals among Hispanic Americans. Questionnaire data were collected from 236 Hispanic participants, including measures of perceived discrimination, optimism, social support, symptoms of trait anxiety, and physical and mental health-related quality of life. Path analysis indicated direct, negative associations between perceived discrimination and both forms of health-related quality of life. Results also showed that these relationships were partially mediated by the reserve capacity variable of optimism and by symptoms of anxiety, though evidence for mediation by anxiety was stronger than for optimism. Findings suggest that perceived discrimination depletes intrapersonal reserves in Hispanic Americans, which, in turn, induces negative emotions. Implications for community-level interventions are discussed.     

The ethno-racial segmentation jobs: The impacts of the occupational stereotypes on hiring decisions

ABSTRACT

This paper considers both the division of the labor market and the occupational stereotyping as explanatory mechanisms of discrimination in hiring decisions. It hypothesized that recruiters would favor candidates applying for a position that is stereotypically identified with their ethnic category. We solicited 146 recruiters in order to evaluate the hireability of either a native-born or an immigrant candidate, either competent or not competent, for either a prestigious or a low-skill occupation, and to justify their decision in writing. As predicted, both the hireability ratings and the narrative comments produced by recruiters showed that native-born applicants were preferred for prestigious jobs while immigrants tended to be selected more often for low-skill positions.The discussion addresses various issues related to decision-making in recruitment settings.     

Relational learning in a context of transposition: a review

In a typical transposition task, an animal is presented with a single pair of stimuli (for example, S3+ S4−, where plus and minus denote reward and nonreward and digits denote stimulus location on a sensory dimension such as size). Subsequently, an animal is presented with a testing pair that contains a previously reinforced or nonreinforced stimulus and a novel stimulus (for example, S2–S3 and S4–S5). Does the choice of a novel S2 instead of previously reinforced S3 in a testing pair S2–S3 indicate that the animal has learned a relation (i.e., “select smaller”)? This review of empirical evidence and theoretical accounts shows that an organism''s behavior in a transposition task is undoubtedly influenced by prior reinforcement history of the training stimuli (Spence, 1937). However, it is also affected by two other factors that are relational in nature—a similarity of two testing stimuli to each other and an overall similarity of the testing pair as a whole to the training pair as a whole. The influence of the two latter factors is especially evident in studies that use multiple pairs of training stimuli and a wide range of testing pairs comprising nonadjacent stimuli (Lazareva, Miner, Young, & Wasserman, 2008; Lazareva, Wasserman, & Young, 2005). In sum, the evidence suggests that both prior reinforcement history and relational information affect an animal''s behavior in a typical transposition task.     

The interaction of temporal generalization gradients predicts the context effect

In a temporal double bisection task, animals learn two discriminations. In the presence of Red and Green keys, responses to Red are reinforced after 1-s samples and responses to Green are reinforced after 4-s samples; in the presence of Blue and Yellow keys, responses to Blue are reinforced after 4-s samples and responses to Yellow are reinforced after 16-s samples. Subsequently, given a choice between Green and Blue, the probability of choosing Green increases with the sample duration-the context effect. In the present study we asked whether this effect could be predicted from the stimulus generalization gradients induced by the two basic discriminations. Six pigeons learned to peck Green following 4-s samples (S(+)) but not following 1-s samples (S(-)) and to peck Red following 4-s samples (S(+)) but not following 16-s samples (S(-)). Temporal generalization gradients for Green and Red were then obtained. Finally, the pigeons were given a choice between Green and Red following sample durations ranging from 1 to 16 s. Results showed that a) the two generalization gradients had the minimum at the S(-) duration, an intermediate value between the S(-) and the S(+) durations, and the maximum at the S(+) as well as more extreme durations; b) on choice trials, preference for Green over Red increased with sample duration, the context effect; and c) the two generalization gradients predicted the average context effect well. The Learning-to-Time model accounts for the major trends in the data.     

Musicians and tone-language speakers share enhanced brainstem encoding but not perceptual benefits for musical pitch

Behavioral and neurophysiological transfer effects from music experience to language processing are well-established but it is currently unclear whether or not linguistic expertise (e.g., speaking a tone language) benefits music-related processing and its perception. Here, we compare brainstem responses of English-speaking musicians/non-musicians and native speakers of Mandarin Chinese elicited by tuned and detuned musical chords, to determine if enhancements in subcortical processing translate to improvements in the perceptual discrimination of musical pitch. Relative to non-musicians, both musicians and Chinese had stronger brainstem representation of the defining pitches of musical sequences. In contrast, two behavioral pitch discrimination tasks revealed that neither Chinese nor non-musicians were able to discriminate subtle changes in musical pitch with the same accuracy as musicians. Pooled across all listeners, brainstem magnitudes predicted behavioral pitch discrimination performance but considering each group individually, only musicians showed connections between neural and behavioral measures. No brain-behavior correlations were found for tone language speakers or non-musicians. These findings point to a dissociation between subcortical neurophysiological processing and behavioral measures of pitch perception in Chinese listeners. We infer that sensory-level enhancement of musical pitch information yields cognitive-level perceptual benefits only when that information is behaviorally relevant to the listener.     

歧视知觉对初中生的合作倾向与行为的影响

本文通过两个研究揭示歧视知觉对初中生合作倾向与行为的影响, 研究1采用问卷法对752名初中生进行为期一年的追踪, 运用潜变量交叉滞后结构方程模型分析歧视知觉与合作倾向之间的纵向预测关系; 研究2采用动态公共物品困境实验考察歧视知觉对合作行为的影响, 以及群体类型的调节作用。结果发现：(1)初中生的歧视知觉与合作倾向存在显著负相关; T1合作倾向可负向预测T2歧视知觉, T2歧视知觉可负向预测T3合作倾向; (2)在公共物品困境前三轮投资比和贡献率上, 歧视知觉和群体类型的交互效应显著; 而在后三轮仅发现歧视知觉在投资比和贡献率上的主效应, 以及群体类型在贡献率上的主效应。以上结果表明, 歧视知觉与合作倾向之间存在纵向螺旋式影响; 歧视知觉对前期合作行为的影响受到群体类型的调节, 但随着互动时间延长, 该调节作用消失。     

Distributional learning has immediate and long-lasting effects

Evidence of distributional learning, a statistical learning mechanism centered on relative frequency of exposure to different tokens, has mainly come from short-term learning and therefore does not ostensibly address the development of important learning processes. The present longitudinal study examines both short- and long-term effects of distributional learning of phonetic categories on non-native sound discrimination over a 12-month period. Two groups of listeners were exposed to a two-minute distribution of auditory stimuli in which the most frequently presented tokens either approximated or exaggerated the natural production of the speech sounds, whereas a control group listened to a piece of classical music for the same length of time. Discrimination by listeners in the two distribution groups improved immediately after the short exposure, replicating previous results. Crucially, this improvement was maintained after six and 12 months, demonstrating that distributional learning has long-lasting effects.