Scientific Understanding and Mathematical Abstraction

This paper argues for two related theses. The first is that mathematical abstraction can play an important role in shaping the way we think about and hence understand certain phenomena, an enterprise that extends well beyond simply representing those phenomena for the purpose of calculating/predicting their behaviour. The second is that much of our contemporary understanding and interpretation of natural selection has resulted from the way it has been described in the context of statistics and mathematics. I argue for these claims by tracing attempts to understand the basis of natural selection from its early formulation as a statistical theory to its later development by R.A. Fisher, one of the founders of modern population genetics. Not only did these developments put natural selection of a firm theoretical foundation but its mathematization changed the way it was understood as a biological process. Instead of simply clarifying its status, mathematical techniques were responsible for redefining or reconceptualising selection. As a corollary I show how a highly idealised mathematical law that seemingly fails to describe any concrete system can nevertheless contain a great deal of accurate information that can enhance our understanding far beyond simply predictive capabilities.

Rapid picture presentation and affective engagement

Emotional reactions were assessed to pictorial stimuli presented in a continuous stream at rapid speeds that compromise conceptual memory and the processing of specific picture content. Blocks of unpleasant, neutral, or pleasant pictures were presented at the rate of either three pictures per second or seven pictures per second. Even with rapid presentation rates, startle reflexes, corrugator muscle activity, and skin conductance responses were heightened when viewing unpleasant pictures. These effects were stronger later in the aversive block, suggesting that cumulative exposure increasingly activates the defense system. The findings suggest that, despite conceptual masking inherent in rapid serial visual presentation, affective pictures prompt measurable emotional engagement.     

The role of childhood abuse and neglect in the sensitization to stressful life events in adolescent depression

This study examined the role of childhood abuse and neglect in sensitizing adolescents to the effects of proximal stressful life events in a cross-sectional sample of 103 depressed and nondepressed adolescents. Consistent with hypotheses, adolescents with a history of childhood abuse and/or neglect reported a lower level of threat of stressful life events prior to episode onset than that reported by those without. This effect was specific to those on their 1st episode of depression and was specific to independent events (i.e., stressors outside of adolescents' control). Further, this effect was robust when controlling for level of chronic difficulties, which was higher in those with childhood abuse and/or neglect. The authors suggest that childhood abuse and/or neglect may be an important risk factor that sensitizes individuals to the effects of acute independent life events.     

Depressive Symptomatology among HIV-Positive Women in the Era of HAART: A Stress and Coping Model

Objective: An enhanced stress and coping model was used to explain depression among HIV-positive women in healthcare and community settings where highly active anti-retroviral treatment (HAART) was commonplace. Method: HIV-infected women in four cities (N=978) were assessed, cross-sectionally, for mental and physical health, stress, social support, and other background factors. Results: Self-reported level of depressive symptomatology was high. Number of physical symptoms, illness intrusiveness, and perceived stress were positively associated with depressed mood, while coping self-efficacy and social support were negatively associated. Stress mediated the effect of health status on depression and coping self-efficacy mediated the effect of psychosocial resources on depression. Our enhanced stress and coping model accounted for 52% of variance in depressive symtpomatology. Conclusions: Interventions focused on improving coping self-efficacy, bolstering social supports, and decreasing stress in the lives of HIV-positive women may help to reduce the negative effects of HIV disease on mood.     

A meta-analysis of the antecedents and consequences of pay level satisfaction

This study reports results from a meta-analysis of 28 correlates of pay level satisfaction involving 240 samples from 203 studies conducted over the past 35 years. Results are presented in 4 categories: primary determinants, antecedents, correlates, and outcomes of pay satisfaction. The authors controlled for pay in examining relations between correlates and pay level satisfaction, as suggested by theory and when primary studies were available to do so. The authors found support for many of the relations suggested by a theoretical model and also note some limitations in the research that has tested this model. The authors recommend changes and additions to the model and suggest additional primary research in specific areas.     

Research ethics for mental health science involving ethnic minority children and youths

In response to U.S. Public Health Service projects promoting attention to disparities in the outcomes of mental health treatments, in July 2001, the American Psychological Association, the National Institute of Mental Health, and the Fordham University Center for Ethics Education convened a group of national leaders in bioethics, multicultural research, and ethnic minority mental health to produce a living document to guide ethical decision making for mental health research involving ethnic minority children and youths. This report summarizes the key recommendations distilled from these discussions.     

A room with a cue: personality judgments based on offices and bedrooms

The authors articulate a model specifying links between (a) individuals and the physical environments they occupy and (b) the environments and observers' impressions of the occupants. Two studies examined the basic phenomena underlying this model: Interobserver consensus, observer accuracy, cue utilization, and cue validity. Observer ratings based purely on offices or bedrooms were compared with self- and peer ratings of occupants and with physical features of the environments. Findings, which varied slightly across contexts and traits, suggest that (a) personal environments elicit similar impressions from independent observers, (b) observer impressions show some accuracy, (c) observers rely on valid cues in the rooms to form impressions of occupants, and (d) sex and race stereotypes partially mediate observer consensus and accuracy. Consensus and accuracy correlations were generally stronger than those found in zero-acquaintance research.     

The nature of adolescents' relationships with their "very important" nonparental adults

As part of a larger program of research on the nature of adolescents' relationships with very important nonparental adults (hereafter referred to as VIPs), a community sample of 243 eleventh graders (mean age = 16.6 years) was surveyed, and a subgroup of 55 adolescents and their VIPs were interviewed about the nature and quality of their relationships. Results showed that (a) adolescent–VIP relationships were a normative component of adolescent development, not a result of problems in adolescents' lives; (b) adolescent–VIP relationships were generally of high quality (e.g., high support, low conflict, and high mutuality); (c) there were significant differences between kin and nonkin VIPs in terms of the duration of relationships and frequency of contact, but not in the quality of relationships; and (d) VIPs whom adolescents designated as extremely important were distinguished from other VIPs in terms of providing a higher level of social support and a higher frequency of contact. Theoretical and practical implications of these findings are discussed.     

An investigation of the line motion effect in a callosotomy patient

When a line is flashed instantaneously between two markers it can appear to propagate from one marker to the other. This illusion is known as the line motion effect. We investigated this effect in the two hemispheres of a callosotomy ("split-brain") patient. We found that both hemispheres perceived the line motion effect, and that flashing one of the markers biased the direction of motion away from that marker regardless of which hemisphere received the stimulus. In contrast, matching the width of the line to the width of one of the markers biased the direction of motion away from the marker only when it appeared in the left visual hemifield. This suggests that multiple mechanisms can contribute to the line motion effect, and that some of these mechanisms rely on different neural structures.