TheP system: A scheme for organizing Pavlovian procedures

The present paper introduces theP system as a scheme for organizing Pavlovian procedures in an orderly and comprehensive manner. The system is defined by three temporal variables and three restrictions on their possible values. It can be used to define all standard temporal variables—namely, stimulus duration, interstimulus interval, trace interval, and intertrial interval—as well as variables C and T of scalar expectancy theory. The system also permits the definition of new independent variables through combinations of the basic temporal parameters. We exemplify this possibility by defining two ratios of temporal intervals. These ratios lead to a space where traditional Pavlovian arrangements (viz., simultaneous, forward-trace, forward-delay, backward) become points on a continuum, and optimal conditions across different experimental preparations become equivalent. Finally, the system can be used to define contingency variables such asp(US/CS),p(US/～CS), and the phi coefficient (φ). In this manner, an organization of different kinds of Pavlovian procedures is achieved on the basis of a single parametric scheme. Such an organization facilitates establishing procedural and theoretical relationships between temporal and contingency variables. The paper concludes with a discussion of certain limitations of the system and other related issues     

Tic douloureux, Parkinson’s disease and the herpes connection

Several cases encountered in psychiatric practice are described in which herpetic involvement of the trigeminal nerve appeared to be crucial to the pathophysiology of the patients’s illness. A brief history of herpes is discussed in terms of the anatomy and physiology of the trigeminal nerve. Particular attention is given to the effects of intraneuronal herpes on gasserian ganglion and spinal nuclei discharge threshoolds, as well as viral pathways directly impacting the substantia nigra. Evidence characterizing Parkinson’s disease as one of several important manifestations of CNS herpes is covered. This article will be presented, by invitation, at the Neuroscience Seminar, Department of Medicine, University of Otago, Dunedin, New Zealand, on 19 August 1997.     

Hume's Utilitarian Theory of Right Action

A theory of right action is implicit in Hume's delineation of the virtues. It gives qualified priority to 'rules of justice' as Hume's remarks on 'that species of utility which attends this virtue' require. It is a useful actual-rule, not an ideal possible-rule, purely utilitarian theory that discounts rules of justice in 'extraordinary cases', has a problem when rules conflict, and invites the question 'Why not hark directly to the supreme law of utility in every case?'. It does not reflect contractarian considerations of mutuality of interests evident in Hume's texts, which while sometimes relevant to what is reasonable, are in his view never also relevant to what is moral.     

Ethical issues in pediatric life-threatening illness: dilemmas of consent, assent, and communication

The treatment of life-threatening illnesses in childhood is replete with ethical issues and with clinical issues that have ethical implications. The central issues are those involved with a child's participation in the decision-making process and with communication of information about the illness and treatments to children. This article examines the questions of patient autonomy and of parental responsibility and prerogative in the context of pediatric oncology. Included in this examination of the ethical dimensions of pediatric life-threatening illness is a discussion of the many related aspects involved, including medical, cultural, psychosocial, legal, and developmental. A multidimensional approach that considers the ways in which these multiple aspects interact with one another, and which focuses on establishing a strong working alliance between the health care team and the pediatric patient's family, can help to avoid or resolve potential ethical and clinical conflicts.     

Prenatal gender preference of mothers of feminine and masculine boys: Relation to sibling sex composition and birth order

A mother's (prenatal) wish for a girl has, at times, been implicated as an etiological factor for boyhood femininity or its DSM-III-R diagnostic equivalent, the Gender Identity Disorder of Childhood. In one sample of 52 feminine and 52 nonclinical control boys from Los Angeles, the proportion of mothers who recalled a wish for a girl during the pregnancy did not differ significantly between groups (26.9% vs. 19.2%, respectively); however, in both groups, the maternal wish for a girl was significantly more common in sibships in which all of the proband's older siblings were male. In a second sample of 103 feminine boys from Toronto, the maternal wish for a girl was significantly higher than that found in the Los Angeles sample (43.7% vs. 26.9%), but a control group was not available; as in the Los Angeles sample, the maternal wish for a girl was significantly more common in sibships in which all of the proband's older siblings were male. Implications of these findings for further study of maternal influences on boyhood femininity are discussed.     

Aggressivity,inattention, hyperactivity,and impulsivity in boys at high and low risk for substance abuse

Aggressivity, inattention, hyperactivity, and impulsivity are cardinal dimensions of externalizing behavior problems of childhood. They are diagnostic and clinical features of childhood disorders, and are thought to be linked to the subsequent development of adult disorders such as substance abuse (SA). Little is known, however, about the convergent and discriminant validity of these four constructs. We used multiple measures to develop indices of aggressivity, inattention, hyperactivity, and impulsivity in a sample of 10- to 12-year-old boys (N=183) with and without a family history of SA. Data were taken from mother reports, child reports, teacher reports, and laboratory tasks. The study aims were (1) to test the convergent and discriminant validity of aggressivity, inattention, hyperactivity, and impulsivity; (2) to examine whether the data were consistent with a model specifying the four constructs as indicators of one superordinate factor; and (3) to differentiate boys with and without a family history of SA in construct scores. The results supported the convergent and discriminant validity of the four constructs. Although discriminable, the constructs covaried strongly and were consistent with a model specifying them as indicators of a single superordinate factor. Boys with a family history of substance abuse scored higher than control boys on aggressivity, inattention, and impulsivity scores, but the groups did not differ on hyperactivity scores. The results are discussed in terms of the role of childhood behavior problems in vulnerability to SA.This work was supported by the National Institute on Drug Abuse grant No. DA 05605.     

Reflections on change in science and religion

Science and the Catholic church are both conservative, slow-to-change institutions. However, science has institutionalized procedures that ensure that ample amounts of criticism of currently accepted theories and methodologies will always be present. This arrangement of continuous conjectures and refutation in science ensures often slow but steady change. Because supporters often think of religions as trafficking in timeless truths, criticism of church beliefs and practices (even when intended to stimulate reflection and improvement) is frequently seen as being disloyal to the institution. Because of the growing crises caused by world overpopulation, I argue that the Catholic church's opposition to all artificial methods of birth control now lacks whatever moral force it might have had when originally promulgated. By highlighting theological perspectives that might be appropriate for the ecological realities of the 21st century, I hope the church will see the wisdom of reevaluating many of its positions in the light of rapidly approaching ecological imperatives.     

Too Close to Quit: The Role of Project Completion in Maintaining Commitment1

Conlon and Garland (1993) demonstrated that information about the degree of project completion, as compared with information about sunk costs, seemed to be the driving force behind continued investment in an R&D project. In the present paper, we replicate and extend this work. In studies with experienced bank managers, Chinese graduate students, and advanced-level MBA students, we find overwhelming support for the importance of project completion on investment intentions, with no indication of typical sunk cost effects. We argue that our results support a goal substitution explanation for many escalation phenomena where, as progress moves forward on a project, completion of the project itself takes increasing precedence over other goals (e. g., economic profit) that may have been more salient at the time the project was initiated.