What 50 years of research tell us about pausing under ratio schedules of reinforcement

Textbooks in learning and behavior commonly describe performance on fixed-ratio schedules as “break and run,” indicating that after reinforcement subjects typically pause and then respond quickly to the next reinforcement. Performance on variable-ratio schedules, on the other hand, is described as steady and fast, with few long pauses. Beginning with Ferster and Skinner''s magnum opus, Schedules of Reinforcement (1957), the literature on pausing under ratio schedules has identified the influences on pausing of numerous important variables, in particular ratio size and reinforcement magnitude. As a result, some previously held assumptions have been called into question. For example, research has shown that the length of the pause is controlled not only by the preceding ratio, as Ferster and Skinner and others had assumed (and as implied by the phrase postreinforcement pause), but by the upcoming ratio as well. Similarly, despite the commonly held belief that ratio pausing is unique to the fixed-ratio schedule, there is evidence that pausing also occurs under variable-ratio schedules. If such widely held beliefs are incorrect, then what about other assumptions? This article selectively examines the literature on pausing under ratio schedules over the past 50 years and concludes that although there may indeed be some common patterns, there are also inconsistencies that await future resolution. Several accounts of pausing under ratio schedules are discussed along with the implications of the literature for human performances, most notably the behaviors termed procrastination.     

Personal values and relational models

In this study, the comprehensive value research by Schwartz (e.g. 1992) was linked to Fiske's relational models theory (RMT, e.g. Fiske, 1991). A sample of 297 people answered the personal values questionnaire (PVQ), the modes of relationship questionnaire (MORQ) and the relationship profile scale (RPS) in a web‐based online survey. As hypothesized, the set of 10 values correlated in a systematic manner—according to the circular structure of personal value systems—with both trait‐like construal of and motivational investment in the relational models communal sharing (CS), authority ranking (AR) and market pricing (MP). Further research concerning a person–environment value congruency approach to predict well‐being is suggested combining the two research traditions. Copyright © 2008 John Wiley & Sons, Ltd.     

A Note on Priest's Finite Inconsistent Arithmetics

We give a complete characterization of Priest's Finite Inconsistent Arithmetics observing that his original putative characterization included arithmetics which cannot in fact be realized.     

Some determinants of latent inhibition in human predictive learning

The present experiments assessed the effects of different manipulations between cue preexposure and cue-outcome pairings on latent inhibition (LI) in a predictive learning task with human participants. To facilitate LI, preexposure and acquisition with the target cues took place while participants performed a secondary task. Presentation of neither the target cues nor the target outcome was anticipated based on the instructions. Experiment 1 demonstrated the LI effect in the new experimental preparation. Experiment 2 analyzed the impact on LI of different activities that participants performed during the interval between preexposure and acquisition. Experiment 3 assessed LI as a function of changes in the secondary task cues made between preexposure and acquisition, namely presenting novel cues and reversing the cue-outcome contingencies. All of the manipulations in Experiments 2 and 3 resulted in a decrease in LI. The attenuation of LI by these manipulations challenges most current theories of learning and is best accommodated by Conditioned Attention Theory (Lubow, Weiner, & Schnur, 1981).     

Limited information estimation and testing of discretized multivariate normal structural models

Discretized multivariate normal structural models are often estimated using multistage estimation procedures. The asymptotic properties of parameter estimates, standard errors, and tests of structural restrictions on thresholds and polychoric correlations are well known. It was not clear how to assess the overall discrepancy between the contingency table and the model for these estimators. It is shown that the overall discrepancy can be decomposed into a distributional discrepancy and a structural discrepancy. A test of the overall model specification is proposed, as well as a test of the distributional specification (i.e., discretized multivariate normality). Also, the small sample performance of overall, distributional, and structural tests, as well as of parameter estimates and standard errors is investigated under conditions of correct model specification and also under mild structural and/or distributional misspecification. It is found that relatively small samples are needed for parameter estimates, standard errors, and structural tests. Larger samples are needed for the distributional and overall tests. Furthermore, parameter estimates, standard errors, and structural tests are surprisingly robust to distributional misspecification. This research was supported by the Department of Universities, Research and Information Society (DURSI) of the Catalan Government, and by grants BSO2000-0661 and BSO2003-08507 of the Spanish Ministry of Science and Technology.     

ANIMALIA,HOMO, AND THE KINGDOM OF GOD

Abstract. I selectively and critically review the state of knowledge about human evolution and the place of humans vis‐à‐vis living apes, with emphasis on bipedal posture and locomotion, expansion of the brain and associated cognitive capacities, speech, tool behavior, culture, and society. I end with a personal perspective on God and Heaven.     

Stress and Adaptation

ABSTRACT— Animal models have contributed considerably to the current understanding of mechanisms underlying the role of stress in health and disease. Despite the progress made already, much more can be made by more carefully exploiting animals' and humans' shared biology, using ecologically relevant models. This allows a fundamental analysis of factors modulating individual adaptive capacity and hence individual vulnerability to disease. This article highlights an emerging scientific approach that uses a framework of interpretation that is more biologically oriented than previous approaches, to evaluate both the adaptive and maladaptive nature of the stress response in relation to existing environmental demands.     

人工神经网络模型在心理学研究中的运用

人工神经网络是对真实神经元网络的粗略模拟,具有容错性、抗干扰性、高效性等特征,具有学习、记忆等强大的认知功能,因此适宜于心理学许多领域的模拟研究。借助神经网络模型不仅可以模拟和验证以往的实验室研究;还能深入探讨感知、联想、学习和记忆等认知过程的具体发生机理,把握其内在机制;它对探讨内隐记忆、内隐学习等无意识认知过程有极大的启发作用。     

词汇的语义表征及其启动效应研究现状与问题

语义启动是研究语义表征的主要范式。在过去的30年里,通过对语义启动效应的研究,词汇的语义表征理论也从符号联结发展到神经联结,其影响因素也逐步重视多方面的交互作用。究其问题,已有研究还存在很多不一致的结论,对语义内在的表征机制和学习机制缺乏深入了解,对影响语义表征的个体因素考虑不多。