An object-oriented simulation of a brain system underlying human aggression

Neural structures involved in aggression were incorporated into a model on the basis of neuro-anatomical data. A software program written in Smalltalk, the Brain Structure Simulator (Seguin, 1994) was used to simulate the effects of activity levels of different brain structures. Relationships among brain structures were then tested by changing activity levels of key structures. Results were consistent with research reports on the brain basis of aggression (Albert, Walsh, & Jonik, 1993; Pontius, 1984).     

Organizational and extraorganizational factors affecting stress,employee well-being,and absenteeism for males and females

The purpose of this research is to examine separately for males and females, the effects of different sources of job and life stress on the emotional and physical well-being of those individuals, and in turn on absenteeism. Results using a sample of 170 males and 204 females indicated that females experienced higher levels of job stress, absenteeism, and poorer emotional well-being. Patterns of relationships for males and females were similar, however, the data suggest that sex moderates the effects of different sources of stress on emotional and physical well-being and absenteeism. The model developed as a part of this research was more complicated for females than for males.     

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.     

Chlorpromazine and serial reaction performance

The effect of 25 mg or 75 mg of chlorpromazine on the serial reaction performance of 12 male human subjects was studied. Speed or number of correct responses was reduced by the high dose of chlorpromazine and errors of commission and omission were increased. The adverse effect of the drug upon speed appeared only at the end of the half-hour test. By contrast the adverse effect upon gaps and errors was apparent throughout the test and there was no interaction with test duration.     

Arbitrariness of frustration: Inhibition or instigation effects on aggression

The purpose of the present research was to assess the relative influence of instigation or inhibition in mediating retaliation after arbitrary or non-arbitrary frustration. Sixty-four men were asked to learn a concept that was being taught by a peer. Although all men were frustrated, half were deliberately frustrated while the other half were not deliberately frustrated by the teacher. Following the task, the learner was given the opportunity to prevent the teacher from gaining employment under conditions where his evaluation was either anonymous or to be made public. The results of a 2 × 2 analysis of variance yielded several significant effects. The data revealed that subjects rejected the teacher more when the frustration was arbitrary than when it was non-arbitrary. Moreover, when the evaluation was anonymous, subjects rejected the teacher more than when the evaluation was to be made public. Furthermore, the difference in the amount of rejection expressed between arbitrary and non-arbitrary conditions was greater when the evaluation was anonymous than when it was public. These results were interpreted as demonstrating the greater contribution of instigatory rather than inhibitory factors in expressing aggression following deliberate or non-deliberate frustration.     

Picture memory: How the action schema affects retention

When an action scene is viewed, an action schema guides the formation of an episodic representation. Within episodic memory, items of high relevance to the theme of the action schema are represented in a prototypical form closely connected to the action theme. In contrast, items of low relevance are represented in detail but their representation is unconnected to that of the action. The action schema is used as a retrieval framework for both recalling and recognizing whether or not an item was depicted in a scene (i.e., item presence), but is not used for recognition of figurative detail (i.e., item appearance). Four experiments confirmed these hypotheses. Children, aged 7- and 9-years, and adults organized pictured scenes around themes from action schemata. The appearance of high relevant items was recognized poorly, while their presence was recalled well. Memory for the presence of high relevant items surpassed that for low relevant items even when recognition of item names was assessed. Conversely, the appearance of low relevant items was recognized accurately, but memory for their presence was difficult to retrieve.     

A SUPERVISORY STRATEGY TO IMPROVE WORK PERFORMANCE FOR LOWER FUNCTIONING RETARDED CLIENTS IN A SHELTERED WORKSHOP

A multiple component strategy was investigated for aiding staff responsible for supervising production of lower functioning retarded clients on contract tasks in an institution-based sheltered workshop. The strategy was assessed in a combined multi-element, multiple baseline across groups design with a reversal component. Production performance increased during the production supervisory strategy with all 16 clients, with the range of increase varying from a few percentage points to 150% of baseline production. Both the clients and staff (responsible for conducting the research) preferred working under experimental conditions rather than under baseline conditions which approximated those found in “typical” sheltered workshops.