Risky business: emotion,decision-making,and addiction

Although metabolic abnormalities in the orbitofrontal cortex have been observed in substance dependent individuals (SDI) for several years, very little attention was paid to the role of this brain region in addiction. However, patients with damage to the ventromedial (VM) sector of the prefrontal cortex and SDI show similar behaviors. (1) They often deny, or they are not aware, that they have a problem. (2) When faced with a choice to pursue a course of action that brings an immediate reward at the risk of incurring future negative consequences, they choose the immediate reward and ignore the future consequences. Studies of patients with bilateral lesions of the VM prefrontal cortex support the view that the process of decision-making depends in many important ways on neural substrates that regulate homeostasis, emotion, and feeling. Parallel lines of study have revealed that VM cortex dysfunction is also evident in subgroups of individuals who are addicted to substances. Thus, understanding the neural mechanisms of decision-making has direct implications for understanding disorders of addiction and pathological gambling, and the switch from a controlled to uncontrolled and compulsive behavior. On the clinical front, the approach to treat addictive disorders has been dominated by a diagnostic system that focuses on behaviors, physical symptoms, or choice of drugs. The article emphasizes the concept of using neurocognitive criteria for subtyping addictive disorders. This is a significant paradigm shift with significant implications for guiding diagnosis and treatment. Using neurocognitive criteria could lead to more accurate subtyping of addictive disorders, and perhaps serve as a guide for more specific, and potentially more successful, behavioral and pharmacological interventions.     

Structural landscape changes in urban and peri-urban agricultural systems of two West African cities and their relations to ecosystem services provided by woody plant communities

Urban Ecosystems - High urbanization pressure in Sub-Saharan Africa led to changes in the composition and configuration of rural and peri-urban agricultural production systems and to the...     

LIFE‐CYCLE PREFERENCES REVISITED

An axiomatic construction for life‐cycle preferences accounting for the finiteness and the randomness of life duration is provided. We emphasize the role of intertemporal correlation aversion and explain why multiplicative preferences provide an interesting alternative to additive preferences, allowing risk aversion and intertemporal elasticity of substitution to be separated. Implications regarding the shape of the optimal consumption profiles are discussed.     

Optimizing trial design in pharmacogenetics research: comparing a fixed parallel group,group sequential,and adaptive selection design on sample size requirements

Two‐stage clinical trial designs may be efficient in pharmacogenetics research when there is some but inconclusive evidence of effect modification by a genomic marker. Two‐stage designs allow to stop early for efficacy or futility and can offer the additional opportunity to enrich the study population to a specific patient subgroup after an interim analysis. This study compared sample size requirements for fixed parallel group, group sequential, and adaptive selection designs with equal overall power and control of the family‐wise type I error rate. The designs were evaluated across scenarios that defined the effect sizes in the marker positive and marker negative subgroups and the prevalence of marker positive patients in the overall study population. Effect sizes were chosen to reflect realistic planning scenarios, where at least some effect is present in the marker negative subgroup. In addition, scenarios were considered in which the assumed ‘true’ subgroup effects (i.e., the postulated effects) differed from those hypothesized at the planning stage. As expected, both two‐stage designs generally required fewer patients than a fixed parallel group design, and the advantage increased as the difference between subgroups increased. The adaptive selection design added little further reduction in sample size, as compared with the group sequential design, when the postulated effect sizes were equal to those hypothesized at the planning stage. However, when the postulated effects deviated strongly in favor of enrichment, the comparative advantage of the adaptive selection design increased, which precisely reflects the adaptive nature of the design. Copyright © 2013 John Wiley & Sons, Ltd.     

The Deep Side of Preference Theory

An individual is said to have a taste for a particular menu, i.e. a subset of available commodities, if he is indifferent between all commodity bundles that contain the same quantity for each commodity which actually is in the menu, whatever the rest of the bundle. Then, a taste is directly defined as a deep property of preferences. As a first result, it is shown that a complete and transitive preference relation over the commodity bundles is equivalent to regular tastes where regularity means that tastes can be derived from a pure qualitative relation between the different commodities. Besides, a preference family based on preference relations corresponding to each particular commodity is said to be rationalizable if there exists a metapreference over commodity bundles which consistently summarizes the preference family and then allows to decide. As a second result, it is shown that if a preference family is rationalizable, then the tastes are organized thanks to a reflexive and transitive qualitative relation between the different commodities.     

Use and Misuse of Indicators in Spatial Planning: The Example of Land Take

The use of indicators to assess the impacts of spatial planning policies has experienced a strong increase in the last decades, despite the difficulties to identify clear causality links in this discipline. The aim of this article is to critically reflect on the impacts of such a phenomenon on spatial planning policies and practices. In order to do so, it explores the issue of land take and how the European Community has set up a policy objective, based on an indicator, to try to tackle the phenomenon.     

On the Processes Underlying the Relationship Between Alexithymia and Gambling Severity

A great number of individuals with persistent problematic gambling behavior exhibit alexithymic tendencies, greater impulsivity, impaired working memory and poor mood. However, the relationship between these cognitive, affective and personality factors in problem gambling remains poorly understood. Our aim was to investigate multiple pathways of the alexithymia and problem gambling relationship. One hundred and six male subjects with different levels of gambling problem severity were recruited. Alexithymia, impulsivity and verbal working memory were evaluated, and their relationships to disordered gambling was examined by means of a path analysis. Results indicate that alexithymia is related to an increase in the severity of gambling indirectly, i.e., through distress severity. In addition, a rise of alexithymic tendencies was also associated with problem gambling severity through enhanced impulsivity that directly increased distress. Working memory capacity failed to significantly impact our path model. Overall, our findings contribute a new finding to the literature by highlighting the importance of alexithymia, in addition to impulsivity, in the understanding of gambling problem severity and its clinical course.     

Impaired Metacognitive Capacities in Individuals with Problem Gambling

Impaired insight into behavior may be one of the clinical characteristics of pathological gambling. In the present study, we tested whether the capacity to evaluate accurately the quality of one’s own decisions during a non-gambling task was impaired in problem gamblers. Twenty-five problem gamblers and 25 matched healthy participants performed an artificial grammar-learning paradigm, in which the quality of choice remains uncertain throughout the task. After each trial of this task, participants had to indicate how confident they were in the grammaticality judgements using a scale ranging from 1 (low confidence) to 7 (high confidence). Results showed that (i), problem gamblers’ performance on the grammaticality test was lower than controls’; (ii) there was a significant correlation between grammaticality judgments and confidence for control participants, which indicates metacognitive insight and the presence of conscious knowledge; (iii) this correlation was not significant in problem gamblers, which suggests a disconnection between performance and confidence in this group. These findings suggest that problem gamblers are impaired in their metacognitive abilities on a non-gambling task, which suggests that compulsive gambling is associated with poor insight as a general factor. Clinical interventions tailored to improve metacognition in gambling could be a fruitful avenue of research in order to prevent pathological gambling.     

Self-Employment and Immigrants' Incorporation: The Case of Turks in Germany

This essay discusses the impact of self-employment on immigrants' incorporation in the host society. It focuses on empirical material coming from Turkish migrants' business activities in Germany. After introducing the main features of contemporary German-Turkish entrepreneurship, the essay presents its socio-economic and cultural consequences for the Turkish minority. Relying on the numerous debates that can be found in the literature, it argues that this impact is ambivalent. In some cases, business ownership may constitute a way of achieving upward social mobility and a path towards a harmonious and pluralistic integration. But it is also frequently a reaction to disadvantage that fosters immigrants' socio-professional vulnerability and that may then lead to ghettoization. The essay then attempts to understand the reasons behind these divergent interpretations and suggests that they lie in the intermediary nature of trade, which is an activity that may connect people from different backgrounds but only in a limited way. Ethnographic observations and the concept of ‘plural societies’ are used to address this aspect of business. The conclusion suggests that, given the globally inferior position of Turkish immigrants, business might not be enough to enable them to catch up.     

The imprint of autocracy on immigrant political participation: Reluctance to participate or to disclosure?

The study investigates the relationship between premigration experiences with autocracy and immigrants' participation in politics in the host country. Using a survey of about 2000 immigrants in Quebec (Canada) interviewed over telephone or with an online questionnaire, it assesses two possible pathways regarding the effect of premigration with autocracy on participation in the host country politics. One pathway emphasizes a reluctance to participate where experiences with autocracy would hinder participation in the host country. The second pathway posits a reluctance to disclosure where experiences with autocracy leave immigrants with a lasting hesitation to reveal the extent of their participation. Our findings lend weak support for a reluctance to participate and instead suggest a reluctance to disclosure. These findings raise questions about our capacity to accurately portray the preferences and behaviours of immigrants, here those who experienced autocracy in the country of origin, and highlight the sensitivity of findings regarding immigrant integration to interview modes.