Clarifying the role of impulsivity in dietary restraint: A structural equation modeling approach

This study was designed to clarify the relationship between the four dimensions of impulsivity in Whiteside and Lynam’s (2001) model and the two aspects of dietary restraint (Concern for Dieting and Weight Fluctuation) in a non-clinical sample. Data were collected from a volunteer community sample (N = 216) of women who responded to two self-report instruments related to impulsivity (UPPS Impulsive Behavior Scale, Whiteside & Lynam, 2001) and dietary restraint (Restraint Scale, Polivy, Herman, & Warsh, 1978). A structural equation model was tested. The model provided a good fit to the data (χ²/df = 1.64, p < .0001, RMSEA = 0.054, 90% CI = 0.050–0.058, p-value for test of close fit (RMSEA > 0.05) = .035) and revealed that Concern for Dieting was positively related to Urgency (standardized β = 0.25, p < .01). Weight Fluctuation was related to lack of Perseverance (standardized β = 0.25, p < .01) and tended to relate to Sensation Seeking (standardized β = 0.17, p = .056). Urgency and lack of Perseverance were found to play a significant role in predicting Concern for Dieting and Weight Fluctuation.     

Categorization and sensorimotor interaction with objects

Three experiments were aimed at verifying whether the modality of interaction with objects and the goals defined by the task influences the weight of the properties used for categorization. In Experiment 1 we used everyday objects (cups and glasses). In order to exclude that the results depended on pre-stored categorical knowledge and to assess the role of a purely perceptual property such as colour, novel objects were used respectively in Experiment 2 and Experiment 3. Participants experienced objects in different modalities of interaction: Vision, Vision+Action, Action, and Mirror (they observed an experimenter touching and lifting them), then they were submitted to a similarity evaluation task and to a more action-based sorting task. Objects varied in intrinsic properties which had a different degree of interactivity: Grip, Shape, Size and Colour. Overall Grip, the most interactive property, was relevant for categorization, together with Size in Experiment 1 and with Shape in Experiment 2 and Experiment 3. The relevance of Grip in the sorting task confirms that goal-relevant properties are more weighted. The absence of a modality effect is discussed in the framework of the theories arguing that the vision of objects and of conspecifics interacting with objects automatically activates motor information.     

Adaptive control of event integration

Identifying 2 target stimuli in a rapid stream of visual symbols is much easier if the 2nd target appears immediately after the 1st target (i.e., at Lag 1) than if distractor stimuli intervene. As this phenomenon comes with a strong tendency to confuse the order of the targets, it seems to be due to the integration of both targets into the same attentional episode or object file. The authors investigated the degree to which people can control the temporal extension of their (episodic) integration windows by manipulating the expectations participants had with regard to the time available for target processing. As predicted, expecting more time to process increased the number of order confusions at Lag 1. This was true for between-subjects and within-subjects (trial-to-trial) manipulations, suggesting that integration windows can be adapted actively and rather quickly.     

Determining the environment: a modal logic for closed interaction

The aim of the work is to provide a language to reason about Closed Interactions, i.e. all those situations in which the outcomes of an interaction can be determined by the agents themselves and in which the environment cannot interfere with they are able to determine. We will see that two different interpretations can be given of this restriction, both stemming from Pauly Representation Theorem. We will identify such restrictions and axiomatize their logic. We will apply the formal tools to reason about games and their regulation.     

Male–male combats in a polymorphic lizard: residency and size,but not color,affect fighting rules and contest outcome

Theoretical models predict that the outcome of dyadic agonistic encounters between males is influenced by resource‐holding potential, resource value, and intrinsic aggressiveness of contestants. Moreover, in territorial disputes residents enjoy a further obvious competitive advantage from the residency itself, owing to the intimate familiarity with their territory. Costs of physical combats are, however, dramatically high in many instances. Thus, signals reliably reflecting fighting ability of the opponents could easily evolve in order to reduce these costs. For example, variation in color morph in polymorphic species has been associated with dominance in several case studies. In this study, we staged asymmetric resident‐intruder encounters in males of the common wall lizard Podarcis muralis, a species showing three discrete morphs (white, yellow, and red) to investigate the effects of asymmetries in color morph, residency, and size between contestants on the outcome of territorial contests. We collected aggression data by presenting each resident male with three intruders of different color morph, in three consecutive tests conducted in different days, and videotaping their interactions. The results showed that simple rules such as residency and body size differences could determine the outcome of agonistic interactions: residents were more aggressive than intruders, and larger males were competitively superior to smaller males. However, we did not find any effect of color on male aggression or fighting success, suggesting that color polymorphism in this species is not a signal of status or fighting ability in intermale conflicts. Aggr. Behav. 35:274–283, 2009. © 2009 Wiley‐Liss, Inc.     

Extended Life

This paper reformulates some of the questions raised by extended mind theorists from an enactive, life/mind continuity perspective. Because of its reliance on concepts such as autopoiesis, the enactive approach has been deemed internalist and thus incompatible with the extended mind hypothesis. This paper answers this criticism by showing (1) that the relation between organism and cogniser is not one of co-extension, (2) that cognition is a relational phenomenon and thereby has no location, and (3) that the individuality of a cogniser is inevitably linked with the question of its autonomy, a question ignored by the extended mind hypothesis but for which the enactive approach proposes a precise, operational, albeit non-functionalist answer. The paper raises a pespective of embedded and intersecting forms of autonomous identity generation, some of which correspond to the canonical cases discussed in the extended mind literature, but on the whole of wider generality. In addressing these issues, this paper proposes unbiased, non-species specific definitions of cognition, agency and mediation, thus filling in gaps in the extended mind debates that have led to paradoxical situations and a problematic over-reliance on intutions about what counts as cognitive.

Causality assessment in epidemiology

Epidemiology relies upon a broad interpretation of determinism. This paper discusses analogies with the evolution of the concept of cause in physics, and analyzes the classical nine criteria proposed by Sir Austin Bradford Hill for causal assessment. Such criteria fall into the categories of enumerative induction, eliminative induction, deduction and analogy. All of these four categories are necessary for causal assessment and there is no natural hierarchy among them, although a deductive analysis of the study design is preliminary to any assessment.     

On the power of multivariate latent growth curve models to detect correlated change

We evaluated the statistical power of single-indicator latent growth curve models (LGCMs) to detect correlated change between two variables (covariance of slopes) as a function of sample size, number of longitudinal measurement occasions, and reliability (measurement error variance). Power approximations following the method of Satorra and Saris (1985) were used to evaluate the power to detect slope covariances. Even with large samples (N = 500) and several longitudinal occasions (4 or 5), statistical power to detect covariance of slopes was moderate to low unless growth curve reliability at study onset was above .90. Studies using LGCMs may fail to detect slope correlations because of low power rather than a lack of relationship of change between variables. The present findings allow researchers to make more informed design decisions when planning a longitudinal study and aid in interpreting LGCM results regarding correlated interindividual differences in rates of development.     

Suicidal behaviors and personality structure

In this paper we suggest the potential clinical usefulness of two projective tests (Rorschach and Object Relation Technique) and of a clinical interview focused on the pathway to suicide, life events, and major life difficulties to better define subtypes of patients attempting suicide. Thirty-three hospitalized subjects who had attempted suicide in the previous 6 months were examined using an in-depth assessment of the pathway to suicide. The aims of this study were: (1) to compare, within a clinical sample of suicidal attempters, the psychopathological, personality, and psychosocial characteristics of subjects with mood disorders alone, personality disorders and dysfunctional personality alone, and mood disorders with personality disorders and/or dysfunctional personality; and (2) to analyze the relationship between the method chosen and the clinical characteristics of the subgroups.