Algorithmic shaping and misbehavior in the acquisition of token deposit by rats

In two experiments, rats were trained to deposit ball bearings down a hole in the floor, using an algorithmic version of shaping. The experimenter coded responses expected to be precursors of the target response, ball bearing deposit; a computer program reinforced these responses, or not, according to an algorithm that mimicked the processes thought to occur in conventional shaping. In the first experiment, 8 of 10 rats were successfully shaped; in the second, 5 of 5 were successfully shaped, and the median number of sessions required was the same as for a control group trained using conventional shaping. In both experiments, “misbehavior,” that is, excessive handling and chewing of the ball bearings, was observed, and when the algorithmic shaping procedure was used, misbehavior could be shown to occur in spite of reduced reinforcement for the responses involved.     

Process and content in an outpatient schizophrenic group

Process and content issues were evaluated during the first six months of an outpatient schizophrenic group. Compared with groups composed of neurotic and characterological patients, the schizophrenic group scored higher in the Avoiding dimension of the Group Climate Questionnaire (GCQ-S). There was more cohesion and less interpersonal conflict as time went on. Although topics related to engagement and differentiation were discussed, there was no obvious GCQ-S evidence of these first two stages of group development. However, the data supported the presence of stage 3 (individuation) during sessions 20–26. Interpersonal topics dominated the group discussions, followed by issues involving reality-testing, expression of emotions, and advice-giving.The authors wish to thank Dr. K. Roy MacKenzie for his helpful comments on a draft of this paper.     

The renormalisation group and effective field theories

Much apprehension has been expressed by philosophers about the method of renormalisation in quantum field theory, as it apparently requires illegitimate procedure of infinite cancellation. This has lead to various speculations, in particular in Teller (1989). We examine Teller's discussion of perturbative renormalisation of quantum fields, and show why it is inadequate. To really approach the matter one needs to understand the ideas and results of the renormalisation group, so we give a simple but comprehensive account of this topic. With this in hand, we explain how renormalisation can and should be understood. One thing that is revealed is that apparently very successful theories such as quantum electro-dynamics cannot be universally true; resolving the tension between success and falsity leads to a picture in which any theory may be viewed as irreducibly phenomenological. We explain how, and argue that the support for this view is tenuous at best.We are very grateful to Stephen Shenker in his patient efforts to help us understand this material, and to the helpful comments of Paul Teller and two anonymous referees. Some of the ideas presented here are based on material in the Ph.D. thesis of one of us (Huggett) submitted to Rutgers University.     

The course of aggression in first-grade children with and without comorbid anxious symptoms

We studied the course of aggressive behavior in an epidemiologically defined sample of first graders with and without comorbid anxious symptoms. Our primary purpose in doing so was to understand whether the stability of aggression in young children was attenuated or strengthened in the presence of comorbid anxiety. Previous studies of older children and adolescents had produced equivocal findings in this regard. Data on anxious symptoms were obtained through an interview of the children, whereas aggressive behavior was assessed through the use of a teacher interview and peer nominations. Assessments were performed in the fall and spring of first grade. In contrast to children classified as aggressive alone in the fall of first grade, boys and girls classified as aggressive and anxious in the fall of first grade were significantly more likely to be classified as aggressive in the spring in terms of teacher ratings and/or peer nominations of aggression. Thus our findings suggest that the link between early and later aggression may be strengthened in the presence of comorbid anxious symptoms, rather than attenuated. Future studies are needed to identify the mechanisms by which the course of aggression is influenced by the presence of comorbid anxiety.The writing of this paper was supported by the following National Institute of Mental Health grants: Epidemiologic Prevention Center for Early Risk Behavior (P50 MH38725); Periodic Outcome of Two Preventive Trials (1RO1 MH42968). The authors would like to thank the Baltimore Public City School System and the children and parents who participated in this study.     

The PsyCLE project: Developing a psychology computer-based learning environment

PsyCLE is a 3-year project involving over 30 United Kingdom universities to develop multimedia resources for introductory psychology courses. Our goal is to support active learning and encourage students to form a sound understanding of concepts under study. The developments focus on interactive tasks, illustrative case study material, and tools to support critical thinking and analysis. We discuss the rationale for the approach adopted and describe the developed resources and their evaluation and use.