The dynamics of Prägnanz

Summary There is quite wide-spread agreement about the relevance of pattern Pragnanz (Koffka, 1935) with respect to the human interpretation of visual patterns. There is less agreement about whether pattern Pragnanz is based solely on pattern information (static) or also on the history of the perceiver (dynamic). In Van Leeuwen and Van den Hof (1991), experimental data concerning serial patterns are presented within the framework of the dynamic-network approach initiated by Buffart (1986, 1987). These experimental data are claimed to give evidence against the static-coding approach initiated by Leeuwenberg (1969, 1971). In the present paper, however, I show first that Buffart's theoretical basis is incorrect, and that in fact Leeuwenberg's static-coding approach is the basis for the dynamic-network approach. Second, I show that those experimental data rather give evidence in favor of the static-coding approach, by using those same data for a test of the most recent static-coding model (Van der Helm & Leeuwenberg, 1991; Van der Helm, Van Lier, & Leeuwenberg, 1992). Finally, I propose a reconciliation between the two approaches, in the sense that the dynamic-network model could be shaped in such a way that it yields a simulation, and maybe even an enrichment, of the static-coding model.     

Conditional Control of Fluid Consumption in an Occasion Setting Paradigm Is Independent of Pavlovian Associations

Drug states, flavors, and contextual cues were each trained as conditional discriminative stimuli to control a saccharin-LiCl association. In transfer tests, drug states transferred control over consumption to other flavored solutions and to food. Contexts and flavors transferred control only to other flavored solutions. Pavlovian control groups given direct pairings of context-LiCl or flavor-LiCl did not show reliable transfer. However, these control groups did show greater or the same aversion to the specific context or flavor predicting LiCl compared to the context or flavor discrimination groups. The dissociation of the discrimination and Pavlovian groups on transfer versus preference tests suggests that performance on the occasion setting task cannot be due to simple excitation or learning about a unique compound cue. Data from extinction procedures provide further support for the dissociation between simple excitation and occasion setting.     

Are beliefs brain-states? And if they are what might that explain?

Philosophical Studies -     

Communication in preterm infants: Why is it different?

The present paper selectively reviews the literature which compares full-term and preterm infants' communication with their mothers in the first year of life. The review is focused not only on what differences are found between full-term and preterm infants, but also why such differences exist. Particular emphasis is placed on the importance of interpreting the findings in the light of the developmental phase of the infants, the heterogeneity of the preterm population and the situation in which communication is studied. Most studies were not designed to consider these issues in any detail. Differences with respect to these factors can be found between studies, however, which may have contributed to the often contradictory findings. Consequently, comparisons between these studies provide clues about the effects of these factors on communicative development. The ultimate goal of this review is to point to important directions for future research on early communication in preterm infants.     

A compensatory approach to optimal selection with mastery scores

A Bayesian approach for simultaneous optimization of test-based decisions is presented using the example of a selection decision for a treatment followed by a mastery decision. A distinction is made between weak and strong rules where, as opposed to strong rules, weak rules use prior test scores as collateral data. Conditions for monotonicity of optimal weak and strong rules are presented. It is shown that under mild conditions on the test score distributions and utility functions, weak rules are always compensatory by nature. The authors are indebted to Wilbert Kallenberg for his valuable comments and to Jan Gulmans for providing the data for the empirical example. The names of the authors are alphabetical; they are equally responsible for the contents of this paper.     

Concordance Between Mothers' and Children's Reports of Somatic and Emotional Symptoms in Patients with Recurrent Abdominal Pain or Emotional Disorders

Mother–child concordance regarding children's somatic and emotional symptoms was assessed in children with recurrent abdominal pain (n = 88), emotional disorders (n = 51), and well children (n = 56). Children between 6 and 18 years of age and their mothers completed questionnaires assessing the children's somatic symptoms, functional disability, and depression. Mothers of children with recurrent abdominal pain reported more child somatic and depressive symptoms than did their children, and mothers of children with emotional disorders reported more child depressive symptoms than did their children. Higher levels of maternal distress were associated with greater mother-child discordance in the direction of mothers reporting more child symptoms than did their children. No significant child age or sex differences were found in concordance patterns.     

A Social Dilemma Analysis of Commuting Preferences: The Roles of Social Value Orientation and Trust1

The current research advances a social dilemma analysis of commuting, examining the roles of preexisting personality differences in social value orientation (i.e., prosocial vs. proself orientation) and trust (i.e., a general belief in the honesty and cooperative intentions of others) in determining preferences for collectively desirable commuting options: preferences for commuting by public transportation (Study 1) and carpooling (Study 2). Consistent with predictions, both studies revealed that, relative to p of prosocials, preferences of proselfs were more strongly associated with beliefs about the relative efficiency of cars (i.e., an outcome affecting personal well-being). Also, greater preferences for collectively desirable actions were observed among prosocials with high trust—relative to prosocials with low trust and proselfs with high or low trust—providing support for the claim that 2 conditions (i.e., prosocial goals and trust in others) must be met to obtain collectively desirable commuting preferences.     

Predicting Adolescents' Initiation of Intercourse and Contraceptive Use

This paper examines whether variables consistent with problem behavior theory predict grade of onset of first intercourse and adoption of effective contraception. A total sample of 3,419 Wisconsin adolescents in Grades 7, 9, and 11 participated in a survey of health-related behaviors administered 3 times across a 6-year period. The sample is 87% White. Multiple regression methods generated different models for onset of sexual intercourse vs. contraceptive adoption. Consistent with problem behavior theory, sexual onset is predicted by the adolescent's behavioral system, perceived peer substance use/abuse, importance of friends, and extent to which the adolescent felt harried and believed it was okay to break laws. Contraceptive adoption is predicted by family structure, socioeconomic variables, and self-esteem. Age and gender model differences emerged.