Drive for thinness, affect regulation and physical activity in eating disorders: a daily life study

Using Ecological Momentary Assessment, the within patient associations between drive for thinness, emotional states, momentary urge to be physically active and physical activity were studied in 32 inpatients with an eating disorder. Participants received an electronic device and had to indicate at nine random times a day during 1 week their momentary drive for thinness, positive and negative emotional states and their urge to be physically active and physical activity. Multilevel analyses indicated that patients with higher mean levels for urge to be physically active were characterized by lower body mass index (BMI) and chronically negative affect whereas patients with higher mean levels for physical activity were characterized by lower BMI and higher dispositions for drive for thinness. In addition, within patient relations between drive for thinness and urge to be physically active were moderated by BMI and chronically negative affect whereas within patient relations between drive for thinness and physical activity were moderated by BMI. Finally, also positive emotional states were significantly associated with physical activity within patients. By using a daily process design, characteristics of physical activity were revealed that have not been identified with assessment methods that have a lower time resolution.     

Breast Cancer as Trauma: Posttraumatic Stress and Posttraumatic Growth

Diagnosis and treatment of cancer has been associated with both posttraumatic stress disorder (PTSD) symptoms and posttraumatic growth (PTG). This cross-sectional study sought to assess the frequency, common predictors, and interrelationships of PTSD symptoms and PTG in breast cancer survivors (n = 65). In this sample, symptoms of PTSD and reports of PTG were common and were not significantly related to one another. Greater social constraints on talking about breast cancer and perception of cancer as a traumatic stressor were associated with greater PTSD symptomatology. Younger age and perception of cancer as a traumatic stressor were associated with greater PTG. Findings suggest the central role of subjective appraisal in adjustment to cancer. Psychosocial interventions should be sensitive to the potential for PTG, both in treatment design and in assessment of outcomes.     

Detecting Design: Fast and Frugal or All Things Considered?

Within the Cognitive Science of Religion, Justin Barrett has proposed that humans possess a hyperactive agency detection device that was selected for in our evolutionary past because ‘over detecting’ (as opposed to ‘under detecting’) the existence of a predator conferred a survival advantage. Within the Intelligent Design debate, William Dembski has proposed the law of small probability, which states that specified events of small probability do not occur by chance. Within the Fine-Tuning debate, John Leslie has asserted a tidiness principle such that, if we can think of a good explanation for some state of affairs, then an explanation is needed for that state of affairs. In this paper I examine similarities between these three proposals and suggest that they can all be explained with reference to the existence of an explanation attribution module in the human mind. The forgoing analysis is considered with reference to a contrast between classical rationality and what Gerd Gigerenzer and others have called ecological rationality.

Daily mood patterns and bulimic behaviors in the natural environment

Objective

Negative affect has been purported to play an important role in the etiology and maintenance of bulimic behaviors. The objective of this study was to identify daily mood patterns in the natural environment exhibited by individuals with bulimia nervosa and to examine the relationship between these patterns and bulimic behaviors.

Method

One hundred thirty-three women aged 18-55 meeting DSM-IV criteria for bulimia nervosa were recruited through clinical referrals and community advertisements. Ecological momentary assessment was used to collect multiple ratings of negative affect, binge eating and purging each day for a two-week period using palmtop computers. Latent growth mixture modeling was used to identify daily mood patterns.

Results

Nine distinct daily mood patterns were identified. The highest rates of binge eating and purging episodes occurred on days characterized by stable high negative affect or increasing negative affect over the course of the day.

Conclusions

These findings support the conclusion that negative mood states are intimately tied to bulimic behaviors and may in fact precipitate such behavior.     

Do maternal stress and home environment mediate the relation between early income‐to‐need and 54‐months attentional abilities?

Using Ecological Systems Theory and stage sequential modelling procedures for detecting mediation, this study examined how early developmental contexts impact preschoolers' performances on a measure of sustained attention and impulse control. Data from 1273 European‐American and African‐American participants in the NICHD Study of Early Child Care were used to identify the potential mediators of the relation between early household income‐to‐need (INR) and 54‐month impulsivity and inattention. Exploratory analyses were also conducted to determine whether the relationships between early income, home environment, parenting stress, and the outcome variables differ for African‐American versus European‐American‐American children. We found modest support for the study hypothesis that 36‐month home environment quality mediated the INR/attention relationship. INR accounted for more home environment score variance and home environment accounted for more Impulsivity score variance for African‐American children. Home environments were related to inattention in the European‐American, but not African‐American, group. Copyright © 2007 John Wiley & Sons, Ltd.     

Two Puzzles for Deontologists: Life-Prolonging Killings and the Moral Symmetry Between Killing and Causing a Person to be Unconscious

Some form of agent-relative constraint against the killing of innocent personsis a central principle in deontological moraltheories. In this article I make two claimsabout this constraint. First, I argue that somekillings of innocents performed incircumstances usually not taken to exculpatethe killer are not even pro tanto wrong.Second, I contend that either there is noagent-relative constraint against the killingof innocents or this constraint has a verydifferent shape from that which deontologistsnormally take it to have. My defence of theseclaims rests on two propositions. First, inkilling someone one may actually prolong thatperson's life. Roughly, life-prolongingkillings are possible, because to kill someoneis to perform an act that causes someone'sdeath and it might well be true that, had onenot performed this act, one's ``victim' wouldhave died earlier. Second, all other thingsbeing equal, killing and causing a person to beunconscious are morally equivalent. Both ofthese propositions are defended in thearticle.     

The EM algorithm for latent class analysis with equality constraints

The EM algorithm is a popular iterative method for estimating parameters in the latent class model where at each step the unknown parameters can be estimated simply as weighted sums of some latent proportions. The algorithm may also be used when some parameters are constrained to equal given constants or each other. It is shown that in the general case with equality constraints, the EM algorithm is not simple to apply because a nonlinear equation has to be solved. This problem arises, mainly, when equality constrints are defined over probabilities indifferent combinations of variables and latent classes. A simple condition is given in which, although probabilities in different variable-latent class combinations are constrained to be equal, the EM algorithm is still simple to apply.The authors are grateful to the Editor and the anonymous reviewers for their helpful comments on an earlier draft of this paper. C. C. Clogg and R. Luijkx are also acknowledged for verifying our results with their computer programs MLLSA and LCAG, respectively.     

Reducing young drivers’ crash risk: Are we there yet? An ecological systems-based review of the last decade of research

The involvement of young novice drivers in road crashes and violations has remained a significant transport and public health issue worldwide. Despite extensive evidence that multiple individual, social, and environmental factors contribute to risk while driving, crashes among young novice drivers have decreased only marginally. There is a need to define clear indicators of risk as well as develop effective interventions.The current study reviews the literature on young novice drivers, including empirical studies, systematic reviews, and crash reports published over the past ten years to provide a synthesis of risk and protective factors across multiple domains, from individual characteristics, to social influences, to behavioural and social interventions, to the car and road environment. Adopting an ecological systems perspective, we discuss links between these domains to clarify the strongest indicators of risk for young novice drivers as compared to experienced drivers, and we collate the available evidence on social and environmental factors that can improve young drivers’ behaviour so to reduce the rate of their road crashes.Among the factors discussed, the incomplete maturation of cognitive skills crucial to safe driving (visual scanning, hazard anticipation, handling of in-vehicle distractions) and the higher susceptibility to social influences (especially peers and parents) emerged as the strongest determinants of discrepancies in performance between young novice and experienced drivers. Growing awareness of the complex array of factors intervening synergistically in young drivers’ risk, as well as technological advancements have led to the design of interventions with some level of effectiveness, however, further research and more robust programmes adopting ecological and holistic approaches are needed to fully address the young driver problem.     

Where do "constraints" come from? A comparison between inferences in biology and in word learning

In this paper, as a commentary on the papers in this special issue, the nature of constraints is discussed in terms of the comparison between inferences in biology and in word learning. Young children's inferences in biology could be constrained by three sources of information: factual knowledge, expectations based on a theory, and ontological knowledge. For example, young children's inference about the length of noses could be constrained by the facts the children know about the animals, the similarity between the animals and humans, and the ontological distinction between living things and nonliving things. In the same way, young children might figure out word meanings by linguistic and pragmatic knowledge, expectations of word meanings (e.g., the whole-object assumption), and ontological knowledge. Interactions among these sources of knowledge are documented by the papers in this special issue and related studies. It is argued that learning biases such as the whole-object assumption could not be induced only by linguistic and pragmatic cues in a social context, but should be regarded as a product of the interaction between a social context and children's theories.