Parents and peer group as mediators of the effect of community structure on adolescent problem behavior

Used a sample of 207 single-parent families residing in 104 small, Midwestern communities to test hypotheses regarding the link between community context and adolescent conduct problems and psychological distress. For boys, community disadvantage had a direct affect on psychological distress, while it indirectly boosted the probability of conduct problems by disrupting parenting and increasing affiliation with deviant peers. Community disadvantage was unrelated to the deviant behavior or emotional well-being of girls. Proportion of single-parent households in the community had a direct effect on girls' conduct problems. It also contributed indirectly to girls' conduct problems by increasing the probability of involvement with deviant peers. Possible explanations for these gender differences are provided. An earlier version of this paper was presented at the annual meeting of the American Society of Criminology, Miami, November 1994. Work on this project was supported by the National Institute of Mental Health (MH48165) and the National Institute of Child Health and Human Development (HD27724). Journal Paper No. 16629 of the Iowa Agriculture and Home Economic Experiment Station, Ames, Iowa. Project No. 3320.     

What is magic about the magical number four?

Summary Previous studies have shown that the apprehension of number can be represented by three models according to the experimental procedure and the data analysis. The present experiment was designed to test the effect of figural characteristics of pattern on the response time. The subjects were asked to perform a same/different judgment, i.e., they were requested to decide whether a dot pattern, shown on a monitor, equalled a previously defined target number (n=2–6) or not. Different types of pattern were used and learning effects were studied. As was expected, the slopes for random and linear patterns were not so steep when the target number was low. With patterns in the dice mode, however, the slope was zero. Repeated presentations led to a slight reduction in slope for random and linear patterns only. In the case of the patterns in the dice mode, the repeated presentations caused only a change in the absolute reaction times (RTs) but had no effect on the slope. When the target numbers were larger (n=5–6), the repeated presentations led to remarkable reductions in slope for random and linear patterns. The slope discontinuity at n=4 occurred with all types of pattern but it became less pronounced in the course of training at least in the case of random and linear patterns. This result is explained by clustering effects, use of figural cues, and a more efficient scanning process.     

Active and passive scene recognition across views.

Recent evidence suggests that scene recognition across views is impaired when an array of objects rotates relative to a stationary observer, but not when the observer moves relative to a stationary display [Simons, D.J., Wang, R.F., 1998. Perceiving real-world viewpoint changes. Psychological Science 9, 315-320]. The experiments in this report examine whether the relatively poorer performance by stationary observers across view changes results from a lack of perceptual information for the rotation or from the lack of active control of the perspective change, both of which are present for viewpoint changes. Three experiments compared performance when observers passively experienced the view change and when they actively caused the change. Even with visual information and active control over the display rotation, change detection performance was still worse for orientation changes than for viewpoint changes. These findings suggest that observers can update a viewer-centered representation of a scene when they move to a different viewing position, but such updating does not occur during display rotations even with visual and motor information for the magnitude of the change. This experimental approach, using arrays of real objects rather than computer displays of isolated individual objects, can shed light on mechanisms that allow accurate recognition despite changes in the observer's position and orientation.     

Non-equilibrium dynamics as an indispensable characteristic of a healthy biological system

Healthy systems in physiology and medicine are remarkable for their structural variability and dynamical complexity. The concept of fractal growth and form offers novel approaches to understanding morphogenesis and function from the level of the gene to the organism. For example, scale-invariance and long-range power-law correlations are features of non-coding DNA sequences as well as of healthy heartbeat dynamics. For cardiac regulation, perturbation of the control mechanisms by disease or aging may lead to a breakdown of these long-range correlations that normally extend over thousands of heartbeats. Quantification of such long-range scaling alterations are providing new approaches to problems ranging from molecular evolution to monitoring patients at high risk of sudden death. We briefly review recent work from our laboratory concerning the application of fractals to two apparently unrelated problems: DNA organization and beat-to-beat heart rate variability. We show how the measurement of long-range power-law correlations may provide new understanding of nucleotide organization as well as of the complex fluctuations of the heartbeat under normal and pathologic conditions.     

AIDS and Perceived Change in Sexual Practice: An Analysis of a College Student Sample from California and Iowa1

The objective of this study was to examine the impact of belief about transmissibility of AIDS and concern about the disease on perceived changes in premarital sexual practices. It was posited that changes in sexual practices are most likely to occur when college students have more certainty about AIDS transmission and greater concern about AIDS. Based on this proposition, dating patterns, premarital sexual permissiveness, attitudes toward homosexuality, sexual orientation, and students' objective perception of AIDS as a problem were used as predictors of concern about AIDS and certainty of sexual transmission. Using a sample of 587 students in the state universities of California and Iowa and focusing on one type of sexual practices (i.e., condom use), it was found that concern about AIDS strongly increases the likelihood of using condoms. Contrary to our prediction, certainty about sexual transmission of AIDS was found to have a marginal effect on students' likelihood of condom use. Furthermore, it was found that monogamous dating, sexual permissiveness, and the degree of perception of AIDS as a problem significantly increase the likelihood of condom use if they are mediated by personal concern about AIDS. The implications are discussed with respect to the usefulness of a theoretical approach and its findings for education on AIDS prevention among college students.     

Diathesis-stress theories in the context of life stress research: implications for the depressive disorders.

Advances in the conceptualization and measurement of life stress in the past 2 decades raise several questions concerning traditional diathesis-stress theories of psychopathology. First, comprehensive measures of life stress force investigators to become more precise about the particular stressful circumstances hypothesized to interact with diatheses. Second, the influence of the diathesis on a person's life is typically ignored, which results in several types of possible bias in the assessment of life stress. Finally, information is available on diatheses and stress for specific disorders to provide a foundation for more empirically based hypotheses about diathesis-stress interactions. This possibility is outlined for depression. Such an approach provides the basis for developing broader, yet more specific, frameworks for investigating diathesis-stress theories of psychopathology in general and of depression in particular.     

Local pragmatics in a Gricean framework

The pragmatic framework developed by H.P. Grice in “Logic and Conversation” explains how a speaker can mean something more than, or different from, the conventional meaning of the sentence she utters. But it has been argued that the framework cannot give a similar explanation for cases where these pragmatic effects impact the understood content of an embedded clause, such as the antecedent of a conditional, a clausal disjunct, or the clausal complement of a verb. In this paper, I show that such an explanation is available. One of the central arguments of the paper (Section 2) is that in a significant subset of cases, local pragmatic effects are a consequence of a global (utterance-level) pragmatic requirement. In these cases, local pragmatic effects are a consequence of ‘acting locally’ to resolve a potential global pragmatic violation. These cases do not require us to posit application of pragmatic principles (Maxims of Conversation) to the contents of embedded clauses. The account does, though, require the assumption that interpreters can identify and reason about the contents of unasserted sub-parts of sentences, an assumption that I motivate in section 3. Building on this, in section 4 of the paper, I argue that once we have recognized that interpreters can, and do, reason independently about the contents of non-asserted clauses, it becomes unproblematic to assume that in some cases, Gricean conversational principles do apply directly to these contents, providing an alternative route to account for local pragmatic effects. In revisiting the ideas of this paper in my response to the commentaries, I consider in more detail the revisions to Grice’s broader program that are necessitated by these moves, in particular acknowledging the problematicity of Grice’s notion of what is said. I argue that the starting point for Gricean reconstructions should instead be merely what is expressed, which carries no pragmatic commitments regarding what is speaker meant.     

Local pragmatics in a Gricean framework,revisited: response to three commentaries

There are two central themes that occupy the commentaries, and hence this response. The first is the character and role of what is said, both in my account, and in pragmatic theory in general. In response, I lay out in more detail the proposal from my original paper that the starting point for Gricean reasoning should be not what is said, but the pragmatically uncommitted what is expressed. As part of this argument, I restate and provide further arguments for my claim that global and local pragmatic effects are continuous. The second central theme of the commentaries concerns the value of a Gricean account, which is not intended to model the psychological processes of interpretation. I respond to this concern in Section 5, ‘Pragmatics, psychology and processing’.