The Probability of Collective Choice with Shared Knowledge Structures

Complex decision making typically involves many agents attempting to aggregate many alternatives. If agents' preferences are unconstrained, cyclic outcomes are highly probable. In contrast, we show that if agents share similar models of the choice domain, then a stable collective outcome occurs with about 90% probability. These results have implications for systems of interacting agents, such as group decisions by individuals in social settings or interpretations of sense data by competing perceptual modules of a brain.     

Perceived attributes of health-promoting laughter: a cross-generational comparison

A small but growing body of empirical data support the popular belief that laughter benefits health. However, there are many varieties of laughter and no reason to assume all varieties should be, or would be, perceived as equally beneficial. The authors examined which types of laughter and which characteristics of laughter people associate with health and whether there are generational differences in this perception. Young adults and older participants rated 12 laughter terms (e.g., chuckle, giggle, belly laugh) on their contribution to health and assessed various aspects of each laughter type on 11 scales. The young adults characterized health-promoting laughter as strong, active, uninhibited, and involving movement; the older participants characterized it as socially appropriate. Both groups associated health-promoting laughter strongly with positive emotion and absence of malice. Implications for placebo effects in laughter interventions are discussed. Differences between humor and laughter and among the proposed mechanisms by which they affect health are clarified.     

Dissociating perceptual and conceptual implicit memory in multiple sclerosis patients

Previous studies indicate that Multiple Sclerosis (MS) patients exhibit deficits in tests of explicit memory such as free recall, but show normal priming on implicit tests of memory such as word stem completion. However, the memory performance of patients with different MS disease subtypes has not been fully examined. In the current study, memory was assessed in Primary Progressive (PPMS), Relapsing Remitting (RRMS), and Secondary Progressive (SPMS) MS subgroups. Explicit memory as well as perceptual and conceptual implicit memory were examined using free recall, word fragment completion, and exemplar generation tests, respectively. All three groups of MS patients exhibited free recall deficits and normal priming on the exemplar generation test. However, the PPMS group exhibited a deficit in word fragment completion priming, whereas the RRMS and SPMS groups exhibited normal levels of priming on this task. Lesion load was assessed using magnetic resonance imaging and was negatively correlated with explicit memory performance, but it did not account for the observed deficits in perceptual implicit memory. The results indicate that PPMS patients exhibit a pattern of memory impairment that is distinct from that of the RRMS and SPMS groups. Moreover, the results indicate that perceptual implicit memory can be neurologically dissociated from conceptual implicit memory.     

What works in prevention. Principles of effective prevention programs

The high prevalence of drug abuse, delinquency, youth violence, and other youth problems creates a need to identify and disseminate effective prevention strategies. General principles gleaned from effective interventions may help prevention practitioners select, modify, or create more effective programs. Using a review-of-reviews approach across 4 areas (substance abuse, risky sexual behavior, school failure, and juvenile delinquency and violence), the authors identified 9 characteristics that were consistently associated with effective prevention programs: Programs were comprehensive, included varied teaching methods, provided sufficient dosage, were theory driven, provided opportunities for positive relationships, were appropriately timed, were socioculturally relevant, included outcome evaluation, and involved well-trained staff. This synthesis can inform the planning and implementation of problem-specific prevention interventions, provide a rationale for multi-problem prevention programs, and serve as a basis for further research.     

Versemaking and lovemaking--W. B. Yeats' "strange second puberty": Norman Haire and the Steinach rejuvenation operation

This article examines the Steinach rejuvenation operation (a vasectomy) which Norman Haire performed on W. B. Yeats in 1934: while this method is now discredited, many others are still used in similar attempts to "cure" old age and restore youthful vitality. The article deals substantially with ideas which were popular among well-read people and intellectuals in the 1920s and 1930s and discusses whether the poet's late-in-life burst of creativity was caused by a medical breakthrough, Haire's more general medical advice, the placebo effect, or by a combination of factors: questions which still have relevance to theories about age, sexuality, and mind-body relationships.     

Correlating brain metabolism with stereotypic and locomotor behavior

Many studies have shown that developmental cocaine exposure alters brain function and behavior; the present study examined the relationship between brain metabolism and behavioral responses to drug challenge. SKF 82958, a selective D1 dopamine agonist, was administered to preweaning cocaine-exposed (50 mg/kg/day) rats and controls at 60 days of age. Deoxyglucose was administered 30 min later, during the peak behavioral response, to measure brain functional activity Pearson product-moment correlations of behavior (locomotor activity and Stereotypic behavior) with rates of glucose metabolism in components of the nigrostriatal and mesolimbic circuits were analyzed. The analysis revealed that under saline-challenge conditions in control animals, rates of metabolism in mesolimbic regions are positively correlated to rates of locomotor activity, whereas in cocaine-treated rats, these correlations were absent. Following SKF challenge, a different pattern was seen; locomotor activity or Stereotypic behavior was not correlated with mesolimbic or nigrostriatal metabolism, respectively,in controls but was positively correlatedin cocaine-treatedrats. Therefore, cocaine exposure during development enhances the coupling of metabolism in components of the mesolimbic and nigrostriatal dopamine systems with the behavioral output associated with these systems under drug-challenge conditions. This may be due to loss of inhibitory influences within the mesolimbic and nigrostriatal systems. Thus, the correlation of behavior and cerebral glucose metabolism provides a unique way of examining the effect of developmental cocaine exposure.     

The role of contextual variables in maternal reactions to children's compliance and noncompliance

The present study was designed to assess whether certain contexts influenced material reactions to children's compliant and noncompliant behavior. Study 1 examined the following contextual variables: chronic negative conditions of the child (physical illness and psychological disturbance) and recent life events experienced by the child (both positive and negative). Study 2 examined maternal mood states as another contextual variable. Results indicated that these contexts relate to differential choices of discipline techniques, based on maternal self-report. These data are examined in light of the literature on treatment acceptability and are discussed in terms of a signal-detection model. Clinical applications are addressed, and suggestions for future research are offered.Portions of this paper were presented at the meeting of the Association for Advancement of Behavior Therapy, Philadelphia, November 1984.We express gratitude to the Research Council of the University of North Carolina at Greensboro for Research Council Grant 2110 218 00000 7719 and to the following for their assistance: James Herbert, Nancy Quinn, Carol Roberson, Ira Turkat, and Marilyn Williams.     

Behavioural interventions in coping with cancer-related pain

Pain is one of the most feared consequences of cancer, often causing significant psychological distress to the patient. The purposes of this paper are (a) to discuss the psychological implications of cancer-related pain, (b) to offer conceptual explanations of the roles behavioural interventions mayplay in reducing cancer-related pain, and (c) to review studies examining the effectiveness of behavioural interventions in reducing cancer-related pain. Clinical issues raised by recent research are addressed, and suggestions for future research are offered. It is concluded that behavioural techniques may serve as a useful adjunct to traditional medical interventions for cancer pain, although considerably more methodologically rigorous research is needed to determine the nature and extent of treatment efficacy.