Reduced neural tracking of prediction error in substance-dependent individuals

Objective: Substance-dependent individuals make poor decisions on the Iowa Gambling Task, a reward-related decisionmaking task that involves risk and uncertainty. Task performance depends on several factors, including how sensitive individuals are to feedback and how well they learn based on such feedback. A physiological signal that guides decision making based on feedback is prediction error. The authors investigated whether disruptions in the neural systems underlying prediction error processing in substance-dependent individuals could account for decision-making performance on a modified Iowa Gambling Task. Methods: Thirty-two substance-dependent individuals and 30 healthy comparison subjects played a modified version of the Iowa Gambling Task during MR scanning. Trial-totrial behavior and functional MRI (fMRI) blood-oxygen-level-dependent (BOLD) signal were analyzed using a computational model of prediction error based on internal expectancies. The authors investigated how well BOLD signal tracked prediction error in the striatum and the orbitofrontal cortex as well as over the whole brain in patients relative to comparison subjects

Risk-taking, delay discounting, and time perspective in adolescent gamblers: an experimental study

Previous research has demonstrated that adult pathological gamblers (compared to controls) show risk-proneness, foreshortened time horizon, and preference for immediate rewards. No study has ever examined the interplay of these factors in adolescent gambling. A total of 104 adolescents took part in the research. Two equal-number groups of adolescent non-problem and problem gamblers, defined using the South Oaks Gambling Screen-Revised for Adolescents (SOGS-RA), were administered the Balloon Analogue Risk Task (BART), the Consideration of Future Consequences (CFC-14) Scale, and the Monetary Choice Questionnaire (MCQ). Adolescent problem gamblers were found to be more risk-prone, more oriented to the present, and to discount delay rewards more steeply than adolescent non-problem gamblers. Results of logistic regression analysis revealed that BART, MCQ, and CFC scores predicted gambling severity. These novel finding provides the first evidence of an association among problematic gambling, high risk-taking proneness, steep delay discounting, and foreshortened time horizon among adolescents. It may be that excessive gambling induces shortsighted behaviors that, in turn, facilitate gambling involvement

Bad Habitus: Anthropology in the Age of the Multimodal

The recent reframing of the Visual Anthropology section in American Anthropologist was motivated by a sense that new technologies have democratizing power and that through multimodal forms we can address a shift toward engagement and collaboration in anthropological research (Collins, Durington, and Gill 2017). Our purpose in this essay is to engage and expand the discussion raised by Samuel Collins, Matthew Durington, and Harjant Gill in their 2017 article \u27Multimodal Anthropology: An Invitation,\u27 which has been widely cited and has helped to inspire a range of new projects in anthropology that do not prioritize text. Although the idea of multimodal anthropology may challenge dominant paradigms of authorship, expertise, capacity, and language, we argue that there is nothing inherently liberatory about multimodal approaches in anthropology. Therefore, as our discipline(s) increasingly advocates for the multimodal in the service of anthropology, there is a need for deep engagement with the multimodal\u27s position as an expression of technoscientific praxis, which is complicit in the reproduction of power hierarchies in the context of global capitalism, \u27capital accumulation\u27 (Collins, Durington, and Gill 2017, 144), and other forms of oppression