Relationships Between Personality and Preferred Substance and Motivations for Use Among Adolescent Substance Abusers

Development and Validation of a Questionnaire for Assessing Drug Use Motives in the General Population in South Korea

Drug use is increasing in South Korea, necessitating evidence-based policy interventions. However, there is a dearth of reliable tools for identifying the personal and psychological factors that drive drug use among Korean adults. In this study, we developed and validated an instrument based on a motivational model to measure drug use motivation in the Korean context. A survey was administered online to 250 Korean adults aged 19-59. Of the initial 37 potential items evaluated, 23 were retained after exploratory factor analysis. Based on their relevance and factor loadings, the final scale consisted of 15 items distributed across five distinct factors: enhancement, coping, social, positive expectancy, and negative expectancy. Confirmatory factor analysis validated the strong fit of the five-factor model. Criterion-related validity was demonstrated by the significant correlations between the five factors and the selected criterion variables. This instrument can be used in research initiatives related to drug addiction and can provide basic data for policy interventions intended to curb drug addiction problems in South Korea. The novelty and broad applicability of this instrument make it invaluable for exploring the psychological underpinnings of drug use in South Korea.

Validation of the Motivational Inventory Underlying Substance Use Engagement (MI-USE)

Given the growing number of fatalities associated with the use of multiple types of drugs, there is an urgent need for a tool that allows clinicians and researchers to quickly assess diverse reasons for substance use. Here, we sought to validate the Motivational Inventory Underlying Substance Engagement (MI-USE), a new measure that assesses motivations for use across different types of substances. Participants were 538 adults ages 18-60 (48% women) who reported substance use problems and past-year drug or alcohol use. Analyses were conducted to discover and validate the factor structure of the MI-USE and evaluate its construct validity. A 30-item model best fit the MI-USE, with one General Factor capturing overall motivation to engage in substance use and eight motive-specific factors that indexed unique motivations for substance use: Emotional Coping (relief from unpleasant emotions), Pleasure-Seeking (feel pleasurable or exciting emotions and sensations), Dependence Severity (avoid withdrawal and cravings), Expansion (enhance self-insight and spirituality), Social Coping (increase confidence and attractiveness), Advantage (gain a physical or mental advantage), Physical Coping (relief from unpleasant bodily sensations), and Sleep (mitigate sleep problems). Evaluation of the measure's construct validity and internal consistency support the chosen model and interpretation of the motive-specific factors. Results provide initial validation of the MI-USE as a reliable and valid tool for assessing diverse substance use motivations. It improves upon existing measures by allowing clinicians and researchers to simultaneously evaluate motivations for multiple forms of substance use, which facilitates personalized treatment planning and research on polysubstance use.

Behavioral Health Risk Factors for Nonmedical Prescription Opioid Use in Adolescence

BACKGROUND

Adolescent nonmedical prescription opioid use is associated with overdose and other adverse outcomes, but its risk factors are poorly understood.

METHODS

Data were drawn from a prospective cohort study of Los Angeles, California, high school students. At baseline (mean age = 14.6 years), students completed self-report screening measures of problem alcohol, cannabis, and drug use and 6 mental health problems (major depression, generalized anxiety, panic disorder, social phobia, obsessive-compulsive disorder, and hypomania or mania). Past 6-month nonmedical prescription opioid use (yes or no) was assessed across 7 semiannual follow-ups.

RESULTS

Among baseline never users of nonmedical prescription opioids (N = 3204), average past 6-month prevalence of new nonmedical prescription opioid use across the 42-month follow-up was 4.4% (range 3.5%-6.1%). In a multivariable model co-adjusting for 9 baseline behavioral problems and other factors, major depression, hypomania or mania, cannabis, alcohol, and other drug use problems were associated with increased odds of nonmedical prescription opioid use over follow-ups. Cumulative indices of behavioral health comorbidity showed successively greater odds of subsequent nonmedical prescription opioid use for students with 1 (odds ratio [OR]: 3.74; 95% confidence interval [CI]: 2.79-5.01), 2 (OR: 8.79; 95% CI: 5.95-12.99), or 3 (OR: 9.69; 95% CI: 5.63-16.68) vs 0 baseline substance use problems, and similar increases were associated with increasing number of mental health problems (1 [OR: 1.60; 95% CI: 1.03-2.88] to all 6 [OR: 3.98; 95% CI: 1.09-14.82] vs 0).

CONCLUSIONS

Behavioral health problems may be associated with increased risk of subsequent nonmedical prescription opioid use during mid to late adolescence, with successively greater risk for those with greater behavioral health comorbidity. In pediatric clinical practice or school-based prevention, behavioral health screeners may be useful for identifying youth at high risk for nonmedical prescription opioid use.

Interpersonal Risk Factors for Suicide in Cocaine Dependence: Association with Self-Esteem, Personality Traits, and Childhood Abuse

OBJECTIVE

Studies have linked cocaine dependence to suicidality. According to the Interpersonal Theory of Suicide, suicidal behavior becomes likely with the simultaneous presence of perceived burdensomeness (PB), lack of (or thwarted) belongingness (TB), and acquired fearlessness about death (FAD). Here, we examined personality and other variables, including depression, self-esteem, childhood abuse, and substance use, as predictors of these risk factors in cocaine-dependent individuals (CDs).

METHODS

Seventy CDs and 70 healthy controls (HCs) participated. We examined group differences in a group-by-sex analysis of variance and identified predictors of PB, TB, and FAD in stepwise regressions.

RESULTS

CDs exhibited elevated PB and TB but not FAD, compared to HCs. CDs also exhibited elevated harm avoidance, novelty seeking, depression, and lower self-esteem and reward dependence. Females reported elevated sexual abuse, harm avoidance, reward dependence, depression, but lower FAD, relative to males, among CDs and HCs. Among CDs, PB was predicted by lower self-esteem and greater emotional abuse; TB was predicted by lower self-esteem and reward dependence, as well as greater emotional and sexual abuse; and FAD was predicted by lower harm avoidance and greater physical abuse.

CONCLUSIONS

Interventions targeting suicidality in cocaine dependence should take into consideration self-esteem, personality traits, and childhood abuse.

Motives for Classical and Novel Psychoactive Substances Use in Psychedelic Polydrug Users

Novel psychoactive substances (NPS) are compounds designed to mimic the effects of existing recreational drugs (classical psychoactive substances [CPS]), while eluding established legal frameworks. Little is known about their effects and potential harms, rendering the increasing number of NPS a challenge to policy makers and researchers alike. Quantitative studies on the motives underlying NPS use are limited, though understanding them is crucial for the design of effective harm prevention strategies. The present study therefore aimed to compare motivational patterns for NPS, CPS, and legal psychoactive substance (LPS) use. An online survey including questions about lifetime drug use, demographics, and motives for use was completed by 2,319 participants of which 1,967 consented and were 18 years or older. Data on lifetime use and endorsed motives are presented for 12 psychoactive substances classified into LPS (alcohol, nicotine), CPS (cannabis, MDMA/ecstasy, amphetamines, cocaine, psilocybin, LSD, ayahuasca), and NPS (synthetic cannabinoids, stimulant, and hallucinogenic) and compared between classes. Across substances, the most frequently endorsed motives were to feel euphoric (58.0%), enhance an activity (52.3%), and broaden consciousness (48.1%). Motives for use were found to differ by substance and gender, with coping-related reasons being more frequent among female participants compared to males who indicated to use for a broad range of reasons. Motivational patterns of CPS and NPS use were largely similar to their classical analogues, this was not the case for synthetic cannabinoids, which had as main endorsed motive getting intoxicated, indiscriminate of specific qualities. This information can feed into tailoring of educational campaigns and prevention strategies.

Clinical Utility of the Personality Assessment Inventory in Predicting Symptom Change and Clinical Outcome in an Inpatient Chemical Dependency Rehabilitation Unit

Newly admitted inpatients in a 28-day chemical dependency rehabilitation unit completed the Personality Assessment Inventory (PAI) at admission and measures of clinical symptomatology (Symptom Checklist-90-Revised) and clinical outcome (Schwartz Outcome Scale-10) at admission and discharge. PAI drug and alcohol scale scores were clinically elevated in this inpatient sample. Modest elevations were found on scales measuring stress, depression, and antisocial and borderline features. Lower scores on most PAI clinical scales were associated with greater symptom reduction and improved psychological well-being, while controlling for pretreatment levels. Multivariate analysis controlling for contributions of clinical scales measuring borderline, depressive, and antisocial traits, as well as pretreatment outcome measures, demonstrated that the PAI Suicidal Ideation and Treatment Rejection scales were significant individual predictors of symptom reduction and improved psychological well-being, respectively, although the treatment scales as a group failed to incrementally contribute to prediction. Overall, the results support the clinical utility of using the PAI to predict clinical improvement among inpatients treated for substance use disorders.

Pathways Relating the Neurobiology of Attachment to Drug Addiction

Substance use disorders constitute a significant public health problem in North America and worldwide. Specifically, substance addictions in women during pregnancy or in the postpartum period have adverse effects not only on the mother, but also on mother-infant attachment and the child's subsequent development. Additionally, there is growing evidence suggesting that parental addiction may be transmitted intergenerationally, where the child of parents with addiction problems is more likely to experience addiction as an adult. The current review takes a developmental perspective and draws from animal and human studies to examine how compromised early experience, including insecure attachment, early abuse/neglect, and unresolved trauma, may influence the development of neurobiological pathways associated with addictions, ultimately increasing one's susceptibility to addictions later in life. We approach this from three different levels: molecular, neuroendocrine and behavioral; and examine the oxytocin affiliation system, dopamine reward system, and glucocorticoid stress response system in this regard. Increased understanding of these underlying mechanisms may help identify key targets for early prevention efforts and inform needed intervention strategies related to both insecure attachment and addiction.

Deletion of Type 2 Metabotropic Glutamate Receptor Decreases Sensitivity to Cocaine Reward in Rats

Cocaine users show reduced expression of the metabotropic glutamate receptor (mGluR2), but it is not clear whether this is a predisposing trait for addiction or a consequence of drug exposure. In this study, we found that a nonsense mutation at the mGluR2 gene decreased mGluR2 expression and altered the seeking and taking of cocaine. mGluR2 mutant rats show reduced sensitivity to cocaine reward, requiring more cocaine to reach satiation when it was freely available and ceasing their drug-seeking behavior sooner than controls when the response requirement was increased. mGluR2 mutant rats also show a lower propensity to relapse after a period of cocaine abstinence, an effect associated with reduced cocaine-induced dopamine and glutamate overflow in the nucleus accumbens. These findings suggest that mGluR2 polymorphisms or reduced availability of mGluR2 might be risk factors for the initial development of cocaine use but could actually protect against addiction by reducing sensitivity to cocaine reward.

The diverse reasons for using Novel Psychoactive Substances - A qualitative study of the users' own perspectives

BACKGROUND

The increasing number of legally ambiguous and precarious Novel Psychoactive Substances (NPS) constitutes a challenge for policy makers and public health. Scientific and more in-depth knowledge about the motivations for using NPS is scarce and often consist of predetermined, non-systematic, or poorly described reasons deduced from top-down approaches. Therefore, the aim of the present study was to explore and characterize the users' self-reported reasons for NPS use inductively and more comprehensively.

METHODS

The self-reported reasons of a self-selected sample of 613 international NPS users were collected via an online survey promoted at the international drug discussion forum bluelight.org and later analyzed qualitatively using inductive thematic analysis.

RESULTS

The analysis showed that the participants used NPS because these compounds reportedly: 1) enabled safer and more convenient drug use, 2) satisfied a curiosity and interest about the effects, 3) facilitated a novel and exciting adventure, 4) promoted self-exploration and personal growth, 5) functioned as coping agents, 6) enhanced abilities and performance, 7) fostered social bonding and belonging, and 8) acted as a means for recreation and pleasure. The consumption of NPS was also driven by 9) problematic and unintentional use.

CONCLUSION

The present study contributed to a more comprehensive understanding of the users' own and self-reported reasons for using NPS, which needs to be acknowledged not only in order to minimize drug related harm and drug user alienation but also to improve prevention efforts and reduce the potentially counter-intuitive effects of strictly prohibitive policies.

Cloninger's Temperament and Character Dimensions of Personality and Binge Drinking Among College Students

BACKGROUND

Temperament and character dimensions of personality remain largely unexplored in young adults exhibiting binge drinking (BD) patterns. Moreover, the available studies do not consider gender differences and dismiss possible personality heterogeneity among binge drinkers. In this study, we aimed to compare temperament and character dimensions between young binge drinkers and age- and sex-matched social drinkers. We further applied cluster analysis to investigate the potential heterogeneity of personality patterns among BD college students.

METHODS

This study included 200 university students of 18 to 24 years of age, who were recruited via an invitation to take an alcohol use survey. These participants included 100 individuals (50 females and 50 males) with a BD pattern, and 100 participants (50 females and 50 males) with a social drinking (SD) pattern. These subjects were evaluated with regard to their use of alcohol and other substances, impulsiveness, sensation seeking, mood, and Cloninger's Temperament and Character Inventory.

RESULTS

Between-group comparisons revealed that both male and female binge drinkers were characterized by high levels of novelty seeking, and low levels of persistence and self-directedness. However, cluster analyses within the binge drinker group revealed 2 distinct groups that differed between males and females. These groups shared similarities with Cloninger's type I (high harm-avoidance) and II (high novelty-seeking) alcoholism typology.

CONCLUSIONS

The present findings support the subdivision of binge drinkers according to gender and personality dimensions. Male and female binge drinkers should not be considered a unitary group, but rather a population of individuals that encompasses at least 2 distinct personality patterns. These findings have major implications for prevention and treatment approaches.

Adolescent Illicit Drug Use and Policy Options in Australia: A Multicriteria Decision Analysis

The etiology of illicit substance involvement is a multidimensional problem shaped by factors across individual, social, and environmental domains. In this study, a multicriteria framework is employed to incorporate the input of specialists regarding risk and protective factors and the effectiveness of alternative interventions to mitigate the adverse harms and consequences associated with adolescent drug initiation and subsequent use. Using a seven-stage drug use continuum (nonuse, priming, initial use, experimental use, occasional use, regular use, and dysfunctional use), experts rate social and environmental factors as the most important from nonuse to occasional use. Experts often support preventive and harm-minimizing strategies to interrupt the progression of drug involvement and accumulation of drug-related harms among adolescents. Compared with preferable interventions, less preferable options (e.g., drug testing/monitoring) are considered to have a negative policy impact on key social, environmental, and drug dimension domains, which tend to override their positive impacts on other areas.

Early adverse experience and substance addiction: dopamine, oxytocin, and glucocorticoid pathways

Substance addiction may follow a chronic, relapsing course and critically undermine the physical and psychological well-being of the affected individual and the social units of which the individual is a member. Despite the public health burden associated with substance addiction, treatment options remain suboptimal, with relapses often seen. The present review synthesizes growing insights from animal and human research to shed light upon developmental and neurobiological pathways that may increase susceptibility to addiction. We examine the dopamine system, the oxytocin system, and the glucocorticoid system, as they are particularly relevant to substance addiction. Our aim is to delineate how early adverse experience may induce long-lasting alterations in each of these systems at molecular, neuroendocrine, and behavioral levels and ultimately lead to heightened vulnerability to substance addiction. We further discuss how substance addiction in adulthood may increase the risk of suboptimal caregiving for the next generation, perpetuating the intergenerational cycle of early adverse experiences and addiction.

Endocannabinoids and striatal function: implications for addiction-related behaviours

Since the identification and cloning of the major cannabinoid receptor expressed in the brain almost 25 years ago research has highlighted the potential of drugs that target the endocannabinoid system for treating addiction. The endocannabinoids, anandamide and 2-arachidonoyl glycerol, are lipid-derived metabolites found in abundance in the basal ganglia and other brain areas innervated by the mesocorticolimbic dopamine systems. Cannabinoid CB1 receptor antagonists/inverse agonists reduce reinstatement of responding for cocaine, alcohol and opiates in rodents. However, compounds acting on the endocannabinoid system may have broader application in treating drug addiction by ameliorating associated traits and symptoms such as impulsivity and anxiety that perpetuate drug use and interfere with rehabilitation. As a trait, impulsivity is known to predispose to addiction and facilitate the emergence of addiction to stimulant drugs. In contrast, anxiety and elevated stress responses accompany extended drug use and may underlie the persistence of drug intake in dependent individuals. In this article we integrate and discuss recent findings in rodents showing selective pharmacological modulation of impulsivity and anxiety by cannabinoid agents. We highlight the potential of selective inhibitors of endocannabinoid metabolism, directed at fatty acid amide hydrolase and monoacylglycerol lipase, to reduce anxiety and stress responses, and discuss novel mechanisms underlying the modulation of the endocannabinoid system, including the attenuation of impulsivity, anxiety, and drug reward by selective CB2 receptor agonists.

Cannabis use motives and personality risk factors

According to the model of substance abuse of Conrod, Pihl, Stewart, and Dongier (2000), four personality factors (i.e., anxiety sensitivity [AS], introversion/hopelessness [I/H], sensation seeking [SS], and impulsivity [IMP]) are associated with elevated risk for substance use/misuse, with each personality factor being related to preference for particular drugs of abuse (e.g., AS with anxiolytics). However, cannabis use has not been consistently linked to any one of these personality factors. This may be due to the heterogeneity in cannabis use motives. The present study explored the association between these four personality risk factors and different cannabis use motives. Cannabis users completed an interview about their motives for cannabis use as well as the self-report Substance Use Risk Profile Scale (SURPS; Woicik, Conrod, Stewart, & Pihl, 2009), which measures the four personality risk factors. Results showed that AS was associated with conformity motives and I/H was associated with coping motives for cannabis use. SS was positively associated with expansion motives and IMP was associated with drug availability motives. Thus, personality risk factors in the model of Conrod et al. (2000) are associated with distinct cannabis use motives in a pattern consistent with theory.

Factors associated with variability and stability of cannabis use in young adulthood

BACKGROUND

This study investigated the factors associated with initiating cannabis use, reverting to cannabis use and remaining a cannabis user in young adulthood. This is an important area of research as the risk for cannabis initiation is extending beyond adolescence and opportunities to influence cannabis use pathways can emerge throughout the life-course.

METHODS

A large, community-based sample was followed prospectively. Data from two successive waves (mean age 23 years and 27 years respectively) of the Path Through Life Study (PATH) were analysed (n=2045). The longitudinal design enabled change in cannabis use in young adulthood to be predicted based on factors assessed approximately four years prior.

RESULTS

An environment of licit drug use was strongly associated with initiating cannabis use (tobacco: OR=4.98, 95%CI: 2.31-10.76) and reverting to cannabis use in young adulthood (alcohol: OR=2.13, 95%CI: 1.42-3.19). Greater fun seeking was found to orientate people towards initiating cannabis use in young adulthood (OR=1.17, 95%CI: 1.04-1.30). Higher psychoticism increased the odds of remaining a cannabis user (OR=1.19, 95%CI: 1.07-1.33). Religious involvement was protective of cannabis initiation (OR=0.89, 95%CI: 0.83-0.95). Early childhood factors did not influence the pattern of cannabis use in young adulthood.

CONCLUSIONS

The findings make an important contribution to the development of prevention and intervention strategies for young adults by drawing attention to specific areas of risk and protection.

Robust changes in reward circuitry during reward loss in current and former cocaine users during performance of a monetary incentive delay task

BACKGROUND

Abnormal function in reward circuitry in cocaine addiction could predate drug use as a risk factor, follow drug use as a consequence of substance-induced alterations, or both.

METHODS

We used a functional magnetic resonance imaging monetary incentive delay task (MIDT) to investigate reward-loss neural response differences among 42 current cocaine users, 35 former cocaine users, and 47 healthy subjects who also completed psychological measures and tasks related to impulsivity and reward.

RESULTS

We found various reward processing-related group differences in several MIDT phases. Across task phases we found a control > current user > former user activation pattern, except for loss outcome, where former compared with current cocaine users activated ventral tegmental area more robustly. We also found regional prefrontal activation differences during loss anticipation between cocaine-using groups. Both groups of cocaine users scored higher than control subjects on impulsivity, compulsivity and reward-punishment sensitivity factors. In addition, impulsivity-related factors correlated positively with activation in amygdala and negatively with anterior cingulate activation during loss anticipation.

CONCLUSIONS

Compared with healthy subjects, both former and current users displayed abnormal brain activation patterns during MIDT performance. Both cocaine groups differed similarly from healthy subjects, but differences between former and current users were localized to the ventral tegmental area during loss outcome and to prefrontal regions during loss anticipation, suggesting that long-term cocaine abstinence does not normalize most reward circuit abnormalities. Elevated impulsivity-related factors that relate to loss processing in current and former users suggest that these tendencies and relationships may pre-exist cocaine addiction.

Increased vulnerability to cocaine in mice lacking dopamine D3 receptors

Neuroimaging studies using positron emission tomography suggest that reduced dopamine D(2) receptor availability in the neostriatum is associated with increased vulnerability to drug addiction in humans and experimental animals. The role of D(3) receptors (D(3)Rs) in the neurobiology of addiction remains unclear, however. Here we report that D(3)R KO (D(3)(-/-)) mice display enhanced cocaine self-administration and enhanced motivation for cocaine-taking and cocaine-seeking behavior. This increased vulnerability to cocaine is accompanied by decreased dopamine response to cocaine secondary to increased basal levels of extracellular dopamine in the nucleus accumbens, suggesting a compensatory response to decreased cocaine reward in D(3)(-/-) mice. In addition, D(3)(-/-) mice also display up-regulation of dopamine transporters in the striatum, suggesting a neuroadaptative attempt to normalize elevated basal extracellular dopamine. These findings suggest that D(3)R deletion increases vulnerability to cocaine, and that reduced D(3)R availability in the brain may constitute a risk factor for the development of cocaine addiction.

Linking ADHD, impulsivity, and drug abuse: a neuropsychological perspective

In this chapter, we consider the relevance of impulsivity as both a psychological construct and endophenotype underlying attention-deficit/hyperactivity disorder (ADHD) and drug addiction. The case for executive dysfunction in ADHD and drug addiction is critically reviewed in the context of dissociable cognitive control processes mediated by the dorsolateral prefrontal cortex (DLPFC), the orbital and ventral medial prefrontal cortex (VMPFC). We argue that such neuroanatomical divisions within the prefrontal cortex are likely to account for the multidimensional basis of impulsivity conceptually categorized in terms of "motoric" and "choice" impulsivity. The relevance of this distinction for the etiology of ADHD and drug addiction is integrated within a novel theoretical framework. This scheme embraces animal learning theory to help explain the heterogeneity of impulse control disorders, which are exemplified by ADHD as a vulnerability disorder for drug addiction.

What have positron emission tomography and 'Zippy' told us about the neuropharmacology of drug addiction?

Translational molecular imaging with positron emission tomography (PET) and allied technologies offer unrivalled applications in the discovery of biomarkers and aetiological mechanisms relevant to human disease. Foremost among clinical PET findings during the past two decades of addiction research is the seminal discovery of reduced dopamine D(2/3) receptor expression in the striatum of drug addicts, which could indicate a predisposing factor and/or compensatory reaction to the chronic abuse of stimulant drugs. In parallel, recent years have witnessed significant improvements in the performance of small animal tomographs (microPET) and a refinement of animal models of addiction based on clinically relevant diagnostic criteria. This review surveys the utility of PET in the elucidation of neuropharmacological mechanisms underlying drug addiction. It considers the consequences of chronic drug exposure on regional brain metabolism and neurotransmitter function and identifies those areas where further research is needed, especially concerning the implementation of PET tracers targeting neurotransmitter systems other than dopamine, which increasingly have been implicated in the pathophysiology of drug addiction. In addition, this review considers the causal effects of behavioural traits such as impulsivity and novelty/sensation-seeking on the emergence of compulsive drug-taking. Previous research indicates that spontaneously high-impulsive rats--as exemplified by 'Zippy'--are pre-disposed to escalate intravenous cocaine self-administration, and subsequently to develop compulsive drug taking tendencies that endure despite concurrent adverse consequences of such behaviour, just as in human addiction. The discovery using microPET of pre-existing differences in dopamine D(2/3) receptor expression in the striatum of high-impulsive rats suggests a neural endophenotype that may likewise pre-dispose to stimulant addiction in humans.

Individuals family history positive for alcoholism show functional magnetic resonance imaging differences in reward sensitivity that are related to impulsivity factors

BACKGROUND

Substance-abusing individuals tend to display abnormal reward processing and a vulnerability to being impulsive. Detoxified alcoholics show differences in regional brain activation during a monetary incentive delay task. However, there is limited information on whether this uncharacteristic behavior represents a biological predisposition toward alcohol abuse, a consequence of chronic alcohol use, or both.

METHODS

We investigated proposed neural correlates of substance disorder risk by examining reward system activity during a monetary incentive delay task with separate reward prospect, reward anticipation, and reward outcome phases in 30 individuals with and 19 without family histories of alcoholism. All subjects were healthy, lacked DSM-IV past or current alcohol or substance abuse histories, and were free of illegal substances as verified by a urine toxicology screening at the time of scanning. Additionally, we explored specific correlations between task-related nucleus accumbens (NAcc) activation and distinct factor analysis-derived domains of behavioral impulsivity.

RESULTS

During reward anticipation, functional magnetic resonance imaging data confirmed blunted NAcc activation in family history positive subjects. In addition, we found atypical activation in additional reward-associated brain regions during additional task phases. We further found a significant negative correlation between NAcc activation during reward anticipation and an impulsivity construct.

CONCLUSIONS

Overall, results demonstrate that sensitivity of the reward circuit, including NAcc, is functionally different in alcoholism family history positive individuals in multiple regards.

Non-medical use of prescription drugs among youth in an Appalachian population: prevalence, predictors, and implications for prevention

This article examines prevalence of non-medical use of prescription drugs (NMUPD) in a sample of elementary and high school students in an Appalachian Tennessee county. We found that lifetime prevalence of NMUPD (35%) was higher than prevalence of cigarette use (28%) and marijuana use (17%), but lower than lifetime prevalence of alcohol use (46%). We examined characteristics, as well as risk and protective factors in several domains, as predictors of NMUPD. For comparison, we also examined these characteristics and factors as predictors of alcohol, cigarette, and marijuana use. Using survey data from a sample of late elementary school and high school students (grades 5, 7, 9, and 11), logistic regression analyses showed that the risk factors of friends' non-medical use and perceived availability, and the protective factors of preceived risk, parents' disapproval, school commitment, and community norms against youth NMUPD were significant predictors of lifetime prevalence of NMUPD. Implications for prevention are discussed.

Substance use in adolescence and psychosis: clarifying the relationship

Adolescence is a time of exploration of the self, and this exploration may involve the use of alcohol and drugs. Sadly, for some, adolescence also marks the first signs of a psychosis. The temporal proximity between the onset of substance use and of psychosis has been the cause of much debate. Here we review the association of alcohol, cannabis, stimulants, and other drugs with psychosis, and we conclude that the use of cannabis and the amphetamines significantly contributes to the risk of psychosis.

A Qualitative Assessment of South African Adolescents' Motivations For and Against Substance Use and Sexual Behavior

Focus groups (N = 15 groups; eight with girls, seven with boys) with adolescents in high schools near Cape Town, South Africa were used to conduct a qualitative investigation of reported reasons for using and not using substances, and for having and not having sex. Adolescents reported Enhancement, Negative States, Social, and Aversive Social motivations for both substance use and sexual behavior. In addition, being addicted as a reason for using drugs and rape as a context for sexual behavior were frequently reported. Motivations against behaviors included Physical/Behavioral Consequences, Ethical Objections, Social Disapproval, and Activities or Future Orientation reasons. Preventive interventions should address existing motivations for and against substance use and sexual behavior to acknowledge adolescents' experiences in context.

Dopamine receptors in the learning, memory and drug reward circuitry

As primary targets of a variety of abused drugs G-protein-coupled dopamine receptors in the brain play an important role in mediating the various drug-induced alterations in neural and psychological processes thought to underlie the transition from voluntary drug use to habitual and progressively compulsive drug-taking. This review considers the functional involvement of the five major dopamine receptor subtypes in drug reinforcement and reward and discusses the development of addiction as a series of learning transitions from initial goal-directed behaviour to pathological stimulus-response habits in which drug-seeking behaviours are automatically elicited and maintained by cues and stimuli associated with drug rewards.

Endocrine and gene expression changes following forced swim stress exposure during cocaine abstinence in mice

RATIONALE

Stress can reinstate previous cocaine-seeking long after drug is no longer present. However, little is known regarding the effect of chronic drug exposure and subsequent drug abstinence on responsivity to stress.

OBJECTIVE

To determine the effect of acute (24-h) and prolonged (14-day) drug-free periods in cocaine-experienced mice on behavioral, endocrine, and molecular outputs following stress exposure.

MATERIALS AND METHODS

Mice were administered a cocaine binge (15 mg/kg, every hour for 3h) for 2 weeks. Following a 24-h or 14-day drug-free period, stress responsivity, along with levels of anxiety, were measured using the forced swim test and elevated zero maze, respectively. In addition, alterations in the levels of plasma corticosterone, corticotrophin-releasing factor (CRF) mRNA, brain-derived neurotrophic factor (BDNF) mRNA, and histone acetylation at their respective promoters were examined following stress exposure.

RESULTS

At both acute and prolonged abstinence time points, behavioral measures were essentially unaltered; however, cocaine-experienced mice exhibited an augmented corticosterone response to the forced swim stress compared to saline-treated mice. Stress exposure increased BDNF mRNA levels in the ventral tegmental area (VTA) and nucleus accumbens (NAc) only in cocaine-experienced mice following a prolonged, but not acute, drug-free period. Increased BDNF mRNA in the NAc was associated with an increase in acetylated histone 3 (AcH3) at the BDNF I promoter. CRF mRNA levels were increased in the amygdala (AMYG); however, this was not associated with alterations in histone acetylation at the promoter.

CONCLUSION

These results demonstrate that drug history and prolonged abstinence can alter the endocrine and molecular responses to stress, which may facilitate the reinstatement of drug-seeking behaviors.

Risk factors for suicide in Taiwanese college students

OBJECTIVE

The authors investigated the personality characteristics, psychopathology, parenting style, and family function among Taiwanese college students with high, moderate, and low suicidal risks.

PARTICIPANTS

The sample included 2,919 first-year college students (1,414 men, 1,505 women) from a university in Taipei, Taiwan.

METHODS

A self-administered questionnaire assessed domains covering demographics, personality, psychopathology, frequency of substance use, parenting style, family functioning, and suicidal behaviors. The authors used mixed models for data analysis.

RESULTS

The authors observed a positive linear trend between increased suicidal tendency and levels of neuroticism, harm avoidance, novelty seeking, psychopathology, and parenting styles of low affection, overprotection, and authoritarian controlling. Use of tobacco and alcohol and impaired family adaptation and cohesion were associated with high and moderate suicidal risks.

CONCLUSIONS

Personality, psychopathology, substance use, and familial factors are important correlates of suicidal risks among college students in Taiwan. Optimal suicide prevention strategies in the college setting should incorporate the multiple facets of suicidal risks.

The developmental antecedents of illicit drug use: evidence from a 25-year longitudinal study

BACKGROUND

The present study examined the developmental antecedents of illicit drug use and abuse/dependence.

METHODS

A 25-year prospective longitudinal study of the health, development, and adjustment of a birth cohort of 1265 New Zealand children. Measures included assessments of adolescent and young adult illicit drug use and abuse/dependence; cannabis use to age 25; measures of parental adjustment; measures of exposure to childhood sexual abuse, physical abuse, and interparental violence; novelty-seeking; childhood and early adolescent adjustment and substance use; and affiliation with substance-using peers.

RESULTS

Illicit drug use and abuse/dependence from ages 16 to 25 were significantly associated (all p values<.05) with a range of parental adjustment measures; exposure to abuse in childhood; individual factors; and measures of childhood and early adolescent adjustment. Analyses using repeated measures logistic regression models suggested that parental illicit drug use, gender, novelty-seeking, and childhood conduct disorder predicted later illicit drug use and abuse/dependence. Further analyses revealed that these pathways to illicit drug use and abuse/dependence were mediated via cannabis use, affiliation with substance-using peers, and alcohol use during ages 16-25.

CONCLUSIONS

The current study suggested that the illicit drug use and abuse/dependence were associated with a range of early life circumstances and processes that put individuals at greater risk of illicit drug use and abuse/dependence. However, the use of cannabis in late adolescence and early adulthood emerged as the strongest risk factor for later involvement in other illicit drugs.

Modelling human drug abuse and addiction with dedicated small animal positron emission tomography

Drug addiction is a chronically relapsing brain disorder, which causes substantial harm to the addicted individual and society as a whole. Despite considerable research we still do not understand why some people appear particularly disposed to drug abuse and addiction, nor do we understand how frequently co-morbid brain disorders such as depression and attention-deficit hyperactivity disorder (ADHD) contribute causally to the emergence of addiction-like behaviour. In recent years positron emission tomography (PET) has come of age as a translational neuroimaging technique in the study of drug addiction, ADHD and other psychopathological states in humans. PET provides unparalleled quantitative assessment of the spatial distribution of radiolabelled molecules in the brain and because it is non-invasive permits longitudinal assessment of physiological parameters such as binding potential in the same subject over extended periods of time. However, whilst there are a burgeoning number of human PET experiments in ADHD and drug addiction there is presently a paucity of PET imaging studies in animals despite enormous advances in our understanding of the neurobiology of these disorders based on sophisticated animal models. This article highlights recent examples of successful cross-species convergence of findings from PET studies in the context of drug addiction and ADHD and identifies how small animal PET can more effectively be used to model complex psychiatric disorders involving at their core impaired behavioural self-control.

Rational choice and environmental deterrence in the retention of mandated drug abuse treatment clients

Length of treatment stay is consistently associated with positive posttreatment outcomes in the rehabilitation of drug-abusing offenders. However, past retention research centered on the examination of individual-level determinants to the exclusion of environmental predictors. In this study, the authors propose a rational choice framework in which treatment retention is viewed as a decision-making process that involves calculation of costs and benefits of remaining in treatment. Environmental factors not directly related to the treatment process are theorized to either reward or punish the course of action taken by each treatment client. Retention data from 1,984 drug-abusing felons diverted for long-term residential treatment were analyzed to test the hypotheses that criminal sanctions against drug offenses, violence in local drug markets, and lack of legitimate job opportunities act as deterrents against premature termination of treatment. Results corroborated the criminal sanction and unemployment hypotheses, but not the violence hypothesis. These findings highlight the necessity of reinforcing perceptions of arrest risks and job prospects during treatment. The study concludes with some clinical recommendations.

Five-factor model personality traits in opioid dependence

BACKGROUND

Personality traits may form a part of the aetiology of opioid dependence. For instance, opioid dependence may result from self-medication in emotionally unstable individuals, or from experimenting with drugs in sensation seekers. The five factor model (FFM) has obtained a central position in contemporary personality trait theory. The five factors are: Neuroticism, Extraversion, Openness to Experience, Agreeableness and Conscientiousness. Few studies have examined whether there is a distinct personality pattern associated with opioid dependence.

METHODS

We compared FFM personality traits in 65 opioid dependent persons (mean age 27 years, 34% females) in outpatient counselling after a minimum of 5 weeks in buprenorphine replacement therapy, with those in a non-clinical, age- and sex-matched sample selected from a national database. Personality traits were assessed by a Norwegian version of the Revised NEO Personality Inventory (NEO PI-R), a 240-item self-report questionnaire. Cohen's d effect sizes were calculated for the differences in personality trait scores.

RESULTS

The opioid-dependent sample scored higher on Neuroticism, lower on Extraversion and lower on Conscientiousness (d = -1.7, 1.2 and 1.7, respectively) than the controls. Effects sizes were small for the difference between the groups in Openness to experience scores and Agreeableness scores.

CONCLUSION

We found differences of medium and large effect sizes between the opioid dependent group and the matched comparison group, suggesting that the personality traits of people with opioid dependence are in fact different from those of non-clinical peers.

Association between morningness-eveningness and behavioral/emotional problems among adolescents

Adolescent eveningness is associated with age, parental monitoring, daytime sleepiness, sleep problems, moodiness, and the use of coffee. This study investigated the association between adolescent morningness-eveningness and psychopathology, substance use, and suicidality in 1332 students ages 12 to 13. Each student-participant completed the Chinese version of the Child Morningness/Eveningness Scale (CMES), the Pubertal Development Scale, and a questionnaire about their sleep schedule, trouble sleeping, habitual substance use, and suicidality. Their mothers completed the Child Behavioral Checklist and Chinese Health Questionnaire. The morning (n = 412), intermediate (n = 740), and evening (n = 180) groups were operationally defined by the CMES t scores. The mixed model was used for data analysis. The evening group had shorter weekday sleep time, longer weekend sleep time, more daytime napping, and greater sleep compensation on weekends and was more likely than the other 2 groups to have behavioral/emotional problems, suicidality, and habitual substance use. Internalizing and externalizing problems partially explained the association between eveningness, substance use, and suicidality. The findings suggest that eveningness may be an indicator for adolescents with behavioral/emotional problems and risky behaviors and suggest an investigation for possible intervention.

Nucleus accumbens D2/3 receptors predict trait impulsivity and cocaine reinforcement

Stimulant addiction is often linked to excessive risk taking, sensation seeking, and impulsivity, but in ways that are poorly understood. We report here that a form of impulsivity in rats predicts high rates of intravenous cocaine self-administration and is associated with changes in dopamine (DA) function before drug exposure. Using positron emission tomography, we demonstrated that D2/3 receptor availability is significantly reduced in the nucleus accumbens of impulsive rats that were never exposed to cocaine and that such effects are independent of DA release. These data demonstrate that trait impulsivity predicts cocaine reinforcement and that D2 receptor dysfunction in abstinent cocaine addicts may, in part, be determined by premorbid influences.

Differential effects of past-year stimulant and sedative drug use on alcohol-related aggression

The goals of this study were to determine the effects of past-year stimulant and sedative drug use on alcohol-related aggression and to examine whether the relation between stimulant drug use and intoxicated aggression is better accounted for by behavioral disinhibition. Participants were 330 healthy social drinkers (164 men and 166 women) between 21 and 35 years of age. Past-year stimulant and sedative use and behavioral disinhibition were assessed via self-report questionnaires. Following the consumption of either an alcohol or a placebo beverage, participants were tested on a modified version of the Taylor Aggression Paradigm [Taylor, S. (1967). Aggressive behavior and physiological arousal as a function of provocation and the tendency to inhibit aggression. Journal of Personality, 35, 297-310] in which mild electric shocks were received from, and administered to, a fictitious opponent. Aggressive behavior was operationalized as the shock intensities administered to the fictitious opponent under conditions of low and high provocation. Results indicated that alcohol significantly strengthened the relation between stimulant drug use and aggression, but only among men. Behavioral disinhibition did not account for this effect. Regardless of past-year drug use, alcohol did not facilitate aggression among women. The present findings suggest that stimulant drug use may be a risk factor for intoxicated aggression for men. However, the underlying mechanisms accounting for this effect remain unclear.