Comorbidity of obsessive–compulsive disorder and substance use disorder: a new heuristic

Obsessive–compulsive disorder (OCD) and substance use disorder share several aspects of phenomenology and may be underpinned by a common mechanism with compulsivity at the core. Despite this overlap, the two disorders show a variable pattern of comorbidity. Here, we review the current evidence for comorbidity across clinical and epidemiological studies, and propose a new heuristic for substance use comorbidity in OCD, based on a hypothetical threshold of OCD severity. Copyright © 2013 John Wiley & Sons, Ltd.     

Reversal-Specific Learning Impairments After a Binge Regimen of Methamphetamine in Rats: Possible Involvement of Striatal Dopamine

A growing body of evidence indicates that protracted use of methamphetamine (mAMPH) causes long-term impairments in cognitive function in humans. Aside from the widely reported problems with attention, mAMPH users exhibit learning and memory deficits, particularly on tasks requiring response control. Although binge mAMPH administration to animals results in cognitive deficits, few studies have attempted to test behavioral flexibility in animals after mAMPH exposure. The aim of this study was to evaluate whether mAMPH would produce impairments in two tasks assessing flexible responding in rats: a touchscreen-based discrimination-reversal learning task and an attentional set shift task (ASST) based on a hallmark test of executive function in humans, the Wisconsin Card Sort. We treated male Long-Evans rats with a regimen of four injections of 2 mg/kg mAMPH (or vehicle) within a single day, a dosing regimen shown earlier to produce object recognition impairments. We then tested them on (1) reversal learning after pretreatment discrimination learning or (2) the ASST. Early reversal learning accuracy was impaired in mAMPH-treated rats. MAMPH pretreatment also selectively impaired reversal performance during ASST testing, leaving set-shifting performance intact. Postmortem analysis of [¹²⁵I]RTI-55 binding revealed small (10–20%) but significant reductions in striatal dopamine transporters produced by this mAMPH regimen. Together, these results lend new information to the growing field documenting impaired cognition after mAMPH exposure, and constitute a rat model of the widely reported decision-making deficits resulting from mAMPH abuse seen in humans.     

The relationship of “passionate attachment” for pornography with sexual compulsivity,frequency of use,and craving for pornography

We recruited a sample of 221 undergraduate males who used pornography regularly to complete a series of questionnaires assessing their “passionate attachment” to pornography, pornography use history, sexual compulsivity, subjective craving to use pornography, compulsive Internet use, social desirability and non-sexual sensation seeking. Both Harmonious Passion and Obsessive Passion subscale scores varied as a function of typical weekly frequency of pornography use, and both subscales were positively significantly associated with sexual compulsivity, current craving to use pornography, and compulsive Internet use. However, neither subtype of passionate attachment to pornography was significantly associated with non-sexual sensation seeking or with the tendency to present oneself in a socially desirable manner. Trait-like sexual compulsivity and presumably transient craving to use pornography appear related to, but are not substitute measures for, passionate attachment for pornography. Further research could evaluate the clinical utility of this questionnaire to measure clients' preoccupation with and inclination to use pornography during assessment and psychotherapy.     

Explanations for the Origins of Sexual Compulsivity Among Gay and Bisexual Men

Sexual compulsivity (SC) is a condition characterized by sexual fantasies and behaviors that interfere with personal, interpersonal, or vocational pursuits. This article describes the ways in which gay and bisexual men with symptoms of SC understand and explain the origins of their condition. The data for this article were drawn from Project SPIN, a mixed-methods study of SC among 183 gay and bisexual men in New York City. The article provides an evaluation of how urban gay and bisexual men experience SC and describes how they think about it in their own words. These men articulated both intrinsic and extrinsic sources for the development of SC. Some participants endorsed a belief in a predisposition toward sexually compulsive behavior, whereas others identified factors such as emotional neglect, sexual abuse, or the availability and accessibility of sexual partners. These understandings may influence the ways in which SC can be treated, while also highlighting issues that may be critical in the identification and/or measurement of SC. Insights into the origins of SC may yield new therapeutic models that reduce not only the distress of contending with this condition but its negative health effects and impact on quality of life.     

Sexual Compulsivity in a Sample of HIV-Positive Methamphetamine-using Gay and Bisexual Men

Little research has been done on the relationship between sexual compulsivity and the sexual risk behaviors of methamphetamine (meth) users. This exploratory study sought to identify correlates of sexual compulsivity in a sample of 217 HIV-positive meth-using gay and bisexual men. Participants reported a mean score of 2.4 on the Sexual Compulsivity Scale (SCS) (SD=.76, range 1–4). Sexual compulsivity was positively associated with high-risk sexual behaviors (e.g., number of unprotected sex acts with anonymous partners, total number of HIV-negative or unknown serostatus partners). In multivariate analyses, higher scores on sexual compulsivity were associated with older age, meth use before or during sex, visits to sex clubs and street corners to find sex partners, lower self-efficacy for condom use, lower levels of self-esteem, higher scores on a measure of disinhibition, and a greater number of HIV-negative or unknown serostatus partners. The results suggest that more attention should be focused on sexual compulsivity and its correlates to determine how they may contribute to resistance to sexual behavior change in this high-risk population.     

Reduced Forebrain Serotonin Transmission is Causally Involved in the Development of Compulsive Cocaine Seeking in Rats

Whereas the majority of cocaine users quit as they experience the negative consequences of drug use, some lose control over their drug taking and compulsively seek drugs. We report that 20% of rats compulsively seek cocaine despite intermittent negative outcomes after escalating their cocaine self-administration. This compulsive subgroup showed marked reductions in forebrain serotonin utilization; increasing serotonin transmission reduced their compulsive cocaine seeking. Depleting forebrain serotonin induced compulsive cocaine seeking in rats with a limited cocaine taking history; this was reversed by systemic treatment with a 5-hydroxytryptamine (5-HT2C) receptor agonist and mimicked by systemic treatment with a 5-HT2C receptor antagonist in intact animals. These results indicate the causal involvement of reduced serotoninergic transmission in the emergence of compulsive drug seeking after a long cocaine-taking history.     

Sexual sensation seeking,sexual compulsivity,and high-risk sexual behaviours among gay/bisexual men in Southwest China

High-risk sexual behaviours (HRSBs), such as having male casual sexual partners (MCSPs) and unprotected anal intercourse (UAI), are combined with a high prevalence of HIV infection among gay/bisexual men. Sexual sensation seeking (SSS) and sexual compulsivity (SC), which are intrapersonal factors, were observed to have associations with HRSB among gay/bisexual men in Western nations. The aim of the study was to examine the relationships between SSS, SC, socio-demographic factors, and HRSB (defined as having MCSP and UAI with MCSP) among self-identified gay and bisexual men in Southwest China. The study was cross-sectional, with a sample of 436 respondents. And their mean age was 24.5 years. The results confirmed that SSS, SC, and sexual attitude are associated with both having MCSP and UAI with MCSP in the Chinese cultural context, among the subgroup of men who have sex with men. Being older, not a student, and having transactional sex in the last 6 months were independently associated with having MCSP. Lower educational level, unemployed, having a relationship with a man, and an unsure HIV status were independently associated with UAI with MCSP. This study indicates that SSS and SC are cross-cultural personality traits related to HRSB. The results of this study may shed light on HIV prevention among gay/bisexual men in China.     

Model-Based Planning Deficits in Compulsivity Are Linked to Faulty Neural Representations of Task Structure

Compulsive individuals have deficits in model-based planning, but the mechanisms that drive this have not been established. We examined two candidates—that compulsivity is linked to (1) an impaired model of the task environment and/or (2) an inability to engage cognitive control when making choices. To test this, 192 participants performed a two-step reinforcement learning task with concurrent EEG recordings, and we related the neural and behavioral data to their scores on a self-reported transdiagnostic dimension of compulsivity. To examine subjects'' internal model of the task, we used established behavioral and neural responses to unexpected events [reaction time (RT) slowing, P300 wave, and parietal-occipital alpha band power] measured when an unexpected transition occurred. To assess cognitive control, we probed theta power at the time of initial choice. As expected, model-based planning was linked to greater behavioral (RT) and neural (alpha power, but not P300) sensitivity to rare transitions. Critically, the sensitivities of both RT and alpha to task structure were weaker in those high in compulsivity. This RT-compulsivity effect was tested and replicated in an independent pre-existing dataset (N = 1413). We also found that mid-frontal theta power at the time of choice was reduced in highly compulsive individuals though its relation to model-based planning was less pronounced. These data suggest that model-based planning deficits in compulsive individuals may arise, at least in part, from having an impaired representation of the environment, specifically how actions lead to future states.SIGNIFICANCE STATEMENT Compulsivity is linked to poorer performance on tasks that require model-based planning, but it is unclear what precise mechanisms underlie this deficit. Do compulsive individuals fail to engage cognitive control at the time of choice? Or do they have difficulty in building and maintaining an accurate representation of their environment, the foundation needed to behave in a goal-directed manner? With reaction time and EEG measures in 192 individuals who performed a two-step decision-making task, we found that compulsive individuals are less sensitive to surprising action–state transitions, where they slow down less and show less alpha band suppression following a rare transition. These findings implicate failures in maintaining an accurate model of the world in model-based planning deficits in compulsivity.