Risk-taking in disorders of natural and drug rewards: neural correlates and effects of probability, valence, and magnitude.

Pathological behaviors toward drugs and food rewards have underlying commonalities. Risk-taking has a fourfold pattern varying as a function of probability and valence leading to the nonlinearity of probability weighting with overweighting of small probabilities and underweighting of large probabilities. Here we assess these influences on risk-taking in patients with pathological behaviors toward drug and food rewards and examine structural neural correlates of nonlinearity of probability weighting in healthy volunteers. In the anticipation of rewards, subjects with binge eating disorder show greater risk-taking, similar to substance-use disorders. Methamphetamine-dependent subjects had greater nonlinearity of probability weighting along with impaired subjective discrimination of probability and reward magnitude. Ex-smokers also had lower risk-taking to rewards compared with non-smokers. In the anticipation of losses, obesity without binge eating had a similar pattern to other substance-use disorders. Obese subjects with binge eating also have impaired discrimination of subjective value similar to that of the methamphetamine-dependent subjects. Nonlinearity of probability weighting was associated with lower gray matter volume in dorsolateral and ventromedial prefrontal cortex and orbitofrontal cortex in healthy volunteers. Our findings support a distinct subtype of binge eating disorder in obesity with similarities in risk-taking in the reward domain to substance use disorders. The results dovetail with the current approach of defining mechanistically based dimensional approaches rather than categorical approaches to psychiatric disorders. The relationship to risk probability and valence may underlie the propensity toward pathological behaviors toward different types of rewards.This is the final version. It was first published by NPG at http://www.nature.com/npp/journal/v40/n4/full/npp2014242a.htm

Gambling and Personality Dimensions

Gambling dates back to ancient times, yet new arenas for gambling, such as the Internet, and methods of assessing psychiatric illness in the modern age have shifted our understanding of gambling as an addiction. Accordingly, Gambling Disorder is now a part of the Addictive Disorders in the DSM-5, which has further catalyzed a debate over the contribution of personality traits (rather than just personality disorders) to the manifestation and maintenance of psychiatric conditions such as Gambling Disorder. This selective review considers relationships between gambling and personality traits. The possible existence of distinct subtypes of Gambling Disorder, defined via personality traits, is highlighted, along with consideration of whether objective neurocognitive markers could serve as proxy markers of ‘personality’ more amenable to scientific dissection rather than relying on questionnaire-based measures alone. The clinical utility of subtyping and future areas of research are discussed.</p

Body Focused Repetitive Behaviors (BFRBs) and Personality Features

Body focused repetitive behaviors (BFRBs) represent a collection of motoric acts that can become ingrained, habitual, and functionally impairing. They often relate to excessive grooming of the body or skin. Although these pathological habits have been described since ancient times, only recently have they been incorporated into psychiatric nosological systems. The relationship between BFRBs and aspects of personality has been scarcely researched. Understanding how formal axis-II personality disorders, questionnaire-based measures of personality, or other putatively enduring traits such as cognitive impairment, relate to the BFRBs may advance our understanding of the core characteristics of the BFRBs and subsequently lead to greater understanding of their pathophysiology and treatment. This article reviews the existing literature surrounding BFRBs and aspects of personality, and highlights limitations in our current understanding of these aspects, along with future research directions.</p

Telescoping phenomenon in pathological gambling:association with gender and comorbidities

The course of pathological gambling (PG) in women has been described as having a later age of initiation but a shorter time to problematic gambling (“telescoped”). This study examined evidence for telescoping and its relationship to comorbidities. 71 treatment-seeking individuals with PG underwent a diagnostic interview to examine gambling behaviors, age at initiation of gambling, and time from initiation to meeting criteria for PG. Women had a higher mean age at gambling initiation compared to men (31.3 ± 13.0 compared to 22.4 ± 7.9 years; p = 0.0003) and a significantly shorter time from initiation of gambling to meeting criteria for PG (8.33 ± 8.7 compared to 11.97 ± 9.1 years; p = 0.0476) after controlling for demographic and clinical variables. This study presents evidence for a gender-specific course of PG unrelated to psychiatric comorbidities and suggests a need for greater clinical focus on the gender differences of gambling behavior