Toward an evolutionary basis for resilience to drug addiction

According to Müller & Schumann (M&S), people would have evolved adaptations for learning to use psychoactive plants and drugs as instruments that reveal particularly advantageous in modern urban environments. Here I "instrumentalize" this framework to propose an evolutionary basis for the existence of a biological resilience to drug addiction in people.     

Elite sport is not an additional source of distress for adolescents with high stress levels

This study examined whether participation in elite sport interacts with stress in decreasing or increasing symptoms of depression and anxiety among adolescents, and further, whether the interplay between participation in high-performance sport and stress is related to the perceived quality of sleep. 434 adolescents (278 girls, 156 boys; age: M = 17.2 yr.) from 15 "Swiss Olympic Sport Classes" and 9 conventional classes answered a questionnaire and completed a 7-day sleep log. Analyses of covariance showed that heightened stress was related to more depressive symptoms and higher scores for trait-anxiety. Moreover, those classified as having poor sleep by a median split cutoff reported higher levels of depressive symptoms. No significant (multivariate) main effects were found for high-performance sport athletes. Similarly, no significant two- or three-way interaction effects were found. These results caution against exaggerated expectations concerning sport participation as a stress buffer. Nevertheless, participation in high-performance sport was not found to be an additional source of distress for adolescents who reported high stress levels despite prior research that has pointed toward such a relationship.     

Relative category-specific preservation in semantic dementia? Evidence from 35 cases

Category-specific deficits have rarely been reported in semantic dementia (SD). To our knowledge, only four previous studies have documented category-specific deficits, and these have focused on the living versus non-living things contrast rather than on more fine-grained semantic categories. This study aimed to determine whether a category-specific effect could be highlighted by a semantic sorting task administered to 35 SD patients once at baseline and again after 2 years and to 10 Alzheimer’s disease patients (AD). We found a relative preservation of fruit and vegetables only in SD.This relative preservation of fruit and vegetables could be considered with regard to the importance of color knowledge in their discrimination. Indeed, color knowledge retrieval is known to depend on the left posterior fusiform gyrus which is relatively spared in SD. Finally, according to predictions of semantic memory models, our findings best fitted the Devlin and Gonnerman’s computational account.     

Group Psychotherapy in France

This article discusses group therapy as part of a multidisciplinary approach to the management of the various psychological and physical rehabilitation concerns posed by kidney and liver transplant candidates and recipients at Howard University Hospital in Washington, DC. The group's history, format, intervention foci, and roles of clinicians and patients attending the group are described and evaluated. Given the relative paucity of research literature in this area, the authors offer recommendations for empirical evaluation of the benefits of multidisciplinary group psychotherapy in ameliorating physical and emotional suffering and prolonging life among transplant patients.     

Further exploration memory bias in compulsive washers

The aim of the present study was to replicate Radomsky and Rachman's findings on memory bias in obsessive-compulsive disorder (OCD), using the same procedure but an increased sample size, more specific control groups, and a full analysis of contamination attribution data. Sixteen OCD-washers, 16 OCD-checkers, 16 social phobic patients and 16 non-anxious controls were presented with 50 'clean' or 'dirty' objects. After this incidental encoding phase, participants were asked to freely recall the objects, to rate their anxiety when almost touching each object, and, finally, to attribute each object to one of the two contamination conditions ('clean' or 'dirty'). Verbal episodic memory was also assessed with the California Verbal Learning Test. The results indicate that, contrary to Radomsky and Rachman's findings, OCD-washers did not differ from the other participants in their memory for 'clean' and 'dirty' objects. However, the OCD-washers recalled more accurately the 'dirty' source of contamination than the 'clean' source. This result was specific to the OCD-washers, and suggests a memory bias for contextually threatening information. The differences between our findings and those published by Radomsky and Rachman's are discussed.     

Towards a theory of collective phenomena. III: Conflicts and forms of power

This paper further develops a new theory of power advanced by the authors in two previous papers (Galam and Moscovici, 1991, 1994). According to this theory power results from the build up of conflicts within a group, these conflicts requiring a degree of organizational complexity which is itselfa decreasing function of group size. Within this approach, power appears to be a composite of three qualitatively different powers, institutional, generative and ecological. Levels and relationships among these forms of power are considered as a function of the diversity of the group. There exist also three states of organization associated with power evolution. At the group initial stage is the paradigmatic state. Creation and inclusion of conflicts are accomplished in the transitional state through the building of complexity. At a critical value of diversity, the group moves into the agonal state in which institutional power vanishes simultaneously with the fusion of generative and ecological powers.     

Two-stage model of visual backward masking: Sensory transmission and accrual of effective information as a function of target intensity and similarity

A functional model is used to describe the effect of target intensity and target-set similarity on backward visual masking. The model consists of two distinct stages of visual information processing. The first stage is related to sensory transduction and transmission and is assumed to require a finite and measurable amount of time during which performance-remains at chance. The second stage, associated with central processing, is characterized by a negatively accelerated growth function reflecting the accrual of effective information. Results show that the duration of the transmission stage is inversely related to target intensity. Surprisingly, the rate of information accrual is an interactive function of both target intensity and target-set similarity. The pattern of results is consistent with the interpretation that both intensity and similarity mediate their effect through a common mechanism—the accrual of effective information.