Substance abuse, pathological gambling, and impulsiveness

A hierarchy of gambling disorders in the community

AIMS

To help refine the definition and diagnosis of gambling disorders, we investigated the distribution among US gamblers of the 10 DSM-IV criteria for Pathological Gambling.

DESIGN

We drew data from two stratified random surveys (n = 2417, n= 530) of gambling behavior and consequences among community-based samples of US adults. A fully structured questionnaire, administered by trained lay interviewers, screened for the life-time prevalence of problem and Pathological Gambling. Per DSM-IV definitions, anyone meeting five or more of 10 itemized criteria was considered a pathological gambler. We analyzed these criteria among all gamblers who met one or more criteria (n = 399).

FINDINGS

Most gamblers who met only one or two criteria reported 'chasing their losses'. At subclinical levels (three to four criteria), gamblers also reported elevated rates of gambling-related fantasy: lying, gambling to escape and preoccupation. Pathological gamblers with five to seven criteria reported marked elevations of loss of control, withdrawal symptoms and tolerance (internalizing dimensions of dependence); risking their social relationships and needing to be bailed out financially (externalizing dimensions). Most of the highest-level pathological gamblers (eight to 10 criteria) reported committing illegal acts to support gambling.

CONCLUSION

Dependence in a biobehavioral sense appears to be a hallmark of Pathological Gambling, but it marks only one threshold in a qualitative hierarchy of disorders beginning with a common subclinical behavior, 'chasing'. Epidemiological assessments and future DSM revisions might consider explicit recognition of a problem gambling disorder, identifying people presenting some cognitive symptoms of Pathological Gambling but not clear signs of dependence. Pathological gamblers in turn appear to have two distinct levels of severity.

Gambling as an Executive Function Task

The Iowa Gambling Task (IGT; Bechara, Damasio, Damasio, & Anderson, 1994) was investigated in relation to fluid intelligence and two conventional executive function tasks: letter fluency and the Wisconsin Card Sorting Test. Fifty-one children aged 8-10 years and a heterogeneous group of 40 adults served as participants. Adults outperformed children on all measures except one; this was the number of good cards selected in the IGT. Intercorrelations among executive function tasks were low. The number of good cards in the IGT appeared to be lower than in previous studies. Reasons for poor performance are discussed. The IGT may possess some shortcomings, which should be investigated in future studies. In clinical usage, the IGT may best serve as a complementary tool to the executive functions test battery.

Pathological gambling severity is associated with impulsivity in a delay discounting procedure

Research and clinical expertise indicates that impulsivity is an underlying feature of pathological gambling. This study examined the extent to which impulsive behavior, defined by the rate of discounting delayed monetary rewards, varies with pathological gambling severity, assessed by the South Oaks Gambling Screen (SOGS). Sixty-two pathological gamblers completed a delay discounting task, the SOGS, the Eysenck impulsivity scale, the Addiction Severity Index (ASI), and questions about gambling and substance use at intake to outpatient treatment for pathological gambling. In the delay discounting task, participants chose between a large delayed reward (US $1000) and smaller more immediate rewards (US $1-$999) across a range of delays (6h to 25 years). The rate at which the delayed reward was discounted (k value) was derived for each participant and linear regression was used to identify the variables that predicted k values. Age, gender, years of education, substance abuse treatment history, and cigarette smoking history failed to significantly predict k values. Scores on the Eysenck impulsivity scale and the SOGS both accounted for a significant proportion of the variance in k values. The predictive value of the SOGS was 1.4 times that of the Eysenck scale. These results indicate that of the measures tested, gambling severity was the best single predictor of impulsive behavior in a delay discounting task in this sample of pathological gamblers.

Brain circuitry and the reinstatement of cocaine-seeking behavior

RATIONALE

Recent studies have attempted to identify the neuroanatomical substrates underlying primed reinstatement of drug-seeking behavior. Identification of neuronal substrates will provide a logical rationale for designing pharmacological interventions in treating drug relapse.

OBJECTIVE

The objective was to identify brain circuitry that is shared between cue-, drug- and stress-primed reinstatement, as well as identifying aspects of brain circuitry that are distinct for each stimulus modality. The resulting circuit offers theoretical interpretations for consideration in future studies.

RESULTS

Aspects of the circuitry mediating reinstatement can be identified with reasonable confidence. The role of the basolateral amygdala in cue-primed reinstatement, the role of the ventral tegmental area in drug-primed reinstatement and the role of adrenergic innervation of the extended amygdala in stress-primed reinstatement are well characterized. Also, all three modes for priming reinstatement may converge on the anterior cingulate cortex and have a final common output through the core of the nucleus accumbens. Lacunae in our understanding of the circuit were identified, especially with regard to how stress priming is conveyed from the extended amygdala to the shared anterior cingulate accumbens core circuit.

CONCLUSIONS

The proposed convergence of priming stimuli into the glutamatergic projection from anterior cingulate to the accumbens core combined with the changes in glutamate transmission and signaling that accompany repeated psychostimulant administration points to the potential value of pharmacological agents that manipulate glutamate release or postsynaptic glutamate receptor signaling and trafficking in treating primed relapse in addicts.

A comparison of treatment-seeking pathological gamblers based on preferred gambling activity

AIMS

To compare and contrast gamblers with different forms of problematic gambling activities. DESIGN, SETTING AND MEASUREMENTS: Pathological gamblers completed the Addiction Severity Index (ASI) and gambling questionnaires when initiating out-patient treatment.

PARTICIPANTS

Participants (n = 347) were categorized by their most problematic form of gambling activity: sports, horse/dog-races, cards, slots and scratch/lottery tickets. Differences in demographics, gambling variables, and ASI composite scores were compared across groups.

FINDINGS

After controlling for demographic variables, the types of gamblers differed in severity of gambling, alcohol and psychiatric problems. Horse/dog-race gamblers were generally older, male and less educated; they began gambling regularly at a young age and spent relatively high amounts of money gambling. Sports gamblers were young males and had intermediary gambling problems; they had relatively high rates of current substance use but few psychiatric problems. Card players spent low to moderate amounts of time and money gambling, and they generally reported few alcohol problems and little psychiatric distress. Slot machine players were older and more likely to be female. Slot gamblers began gambling later in life, had high rates of bankruptcy and reported psychiatric difficulties. Scratch/lottery gamblers spent the least amount of money gambling, but they gambled the most frequently and had relatively severe alcohol and psychiatric symptoms.

CONCLUSIONS

Gambling patterns and severity of psychosocial problems vary by form of problematic gambling, and these differences may influence treatment recommendations and outcomes.

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.

Neurodevelopment, impulsivity, and adolescent gambling

The prevalence of problem and pathological gambling in adolescence and young adulthood has been found to be two- to fourfold higher than in adulthood. Given that these high rates might predict future increases across all age groups, it is important to explore the causes of the elevated rates of problem and pathological gambling among youths. This article reviews evidence for a neurobiological basis for adolescent vulnerability to problem and pathological gambling behaviors. We propose that a common trait motif of impulsivity might underlie phenomenology of pathological gambling, commonly comorbid psychiatric disorders, and related aspects of adolescent behavior. Recent advances in understanding the brain mechanisms involved in motivation, reward, and decision-making allow a discussion of neural circuitry underlying impulsivity. Emerging data indicate that important neurodevelopmental events during adolescence occur in brain regions associated with motivation and impulsive behavior. We hypothesize that immaturity of frontal cortical and subcortical monoaminergic systems during normal neurodevelopment underlies adolescent impulsivity as a transitional trait-behavior. While these neurodevelopmental processes may confer advantage by promoting a learning drive for optimal adaptation to adult roles, they may also confer an increased vulnerability to addictive behaviors such as problem and pathological gambling. An exploration of the developmental changes in neural circuitry involved in impulse control has significant implications for understanding adolescent behaviors and treating problem and pathological gambling among youths.

Evolutionary mismatch, neural reward circuits, and pathological gambling

Evolutionary mismatch theory has been applied to disorders of self-regulation such as maladaptive eating patterns and drug abuse. Modern gambling represents a refinement of the elements of risk and chance, which draw upon the faculties of judgment and novelty-seeking. A set of neuroanatomical structures, including prefrontal-subcortical systems and associated limbic structures, have been implicated in the processing of reward and punishment, including gambling-related situations. Neurobiological systems guiding choice and behavior have evolved to maximize chances for survival under hunter-gatherer conditions, and modern gambling represents an abrupt departure from these circumstances, sometimes resulting in pathological gambling.

Impulsive decision making and working memory

Decision making that favors short-term over long-term consequences of action, defined as impulsive or temporally myopic, may be related to individual differences in the executive functions of working memory (WM). In the first 2 experiments, participants made delay discounting (DD) judgments under different WM load conditions. In a 3rd experiment, participants high or low on standardized measures of imupulsiveness and dysexecutive function were asked to make DD judgments. A final experiment examined WM load effects on DD when monetary rewards were real rather than hypothetical. The results showed that higher WM load led to greater discounting of delayed monetary rewards. Further, a strong direct relation was found between measures of impulsiveness, dysexecutive function,and discounting of delayed rewards. Thus, limits on WM function, either intrinsic or extrinsic, are predictive of a more impulsive decision-making style.

Enhanced intensity dependence as a marker of low serotonergic neurotransmission in borderline personality disorder

Dysfunction of central serotonergic activity has been assumed in patients with borderline personality disorder (BPD) characterized by a prominent impulsive behavioral style. Following the high serotonergic innervation of the primary auditory cortex, there is increasing evidence of the intensity dependence of auditory evoked potentials (AEP), especially the N1/P2 component, indicating serotonergic neurotransmission in animals and humans. 15 females who met the IPDE-criteria for BPD and a group of comparative healthy females (controls) completed extensive personality questionnaires which gave special regard to impulsiveness. We obtained event-related AEP through the application of various loudness stimuli. We examined the relevant N1/P2 amplitude of the tangential dipole of the auditory evoked response using dipole source analysis. The augmentation of the N1/P2 amplitude of tangential dipole source activity with rising stimulus intensity was significantly pronounced in BPD as opposed to controls, accompanied by a reduction in N1 and P2 latencies. The strong loudness dependency of AEP correlated with aspects of impulsiveness. These data imply reduced inhibiting control over cortical sensory processing in BPD. Our findings contribute a further argument to the hypothesis of low serotonergic neurotransmission in BDP and may point to a trait character of impulsiveness in this personality disorder.

The South Oaks Gambling Screen: a review with reference to Australian use

The South Oaks Gambling Screen (SOGS) is a psychometric instrument widely used internationally to assess the presence of pathological gambling. Developed by Lesieur and Blume (1987) in the United States of America (USA) as a self-rated screening instrument, it is based on DSM-III and DSM-III-R criteria. This paper describes the origins and psychometric development of the SOGS and comments critically in relation to its construct validity and cutoff scores. Reference is made to the use of the SOGS in the Australian setting, where historically gambling has been a widely accepted part of the culture, corresponding to one of the highest rates of legaliZed gambling and gambling expenditure in the world. An alternative approach to the development of an instrument to detect people who have problems in relation to gambling is proposed.

The role of cortisol suppression on craving for and satisfaction from nicotine in high and low impulsive subjects

The rewarding properties of drug self-administration have been shown to depend on mesolimbic dopamine release but also on the availability of corticosterone, as shown in rats. Since this became particularly evident when tested in rat strains bred for high (HR) and low (LR) reactivity to novel stimuli, the role of cortisol and personality in drug craving was investigated in 60 male nicotine-deprived smokers divided according to questionnaire scores into high and low impulsives, a dimension considered to represent HR/LR rats. They either received the peripheral cortisol blocker metyrapone (MET) or the centrally blocking substance dexamethasone (DEX) or placebo (n=20 each) and were then allowed to smoke. MET more than DEX reduced craving for cigarettes during deprivation. This was only observed in low impulsives while high impulsives developed low craving unmodified by blockade of cortisol. Satisfaction from smoking was less achieved with DEX than with MET and not modified by impulsivity. Differences between MET and DEX in influencing craving during deprivation and satisfaction from smoking were discussed on the basis of different glucocorticoid receptors. The mineralocorticoid receptor (MR) seems to be the 'turn on switch' and the glucocorticoid receptor (GR) the 'turn off switch' in mediating the rewarding properties of dopamine in drug self-administration.

Evaluation of a behavioral measure of risk taking: the Balloon Analogue Risk Task (BART)

The present study (N = 86) sought to evaluate a laboratory-based behavioral measure of risk taking (the Balloon Analogue Risk Task; BART) and to test associations between this measure and self-report measures of risk-related constructs as well as self-reported real-world risk behaviors. The BART evidenced sound experimental properties, and riskiness on the BART was correlated with scores on measures of sensation seeking, impulsivity, and deficiencies in behavioral constraint. Also, riskiness on the BART was correlated with the self-reported occurrence of addictive, health, and safety risk behaviors, with the task accounting for variance in these behaviors beyond that accounted for by demographics and self-report measures of risk-related constructs. These results indicate that the BART may be a useful tool in the assessment of risk taking.

A pathways model of problem and pathological gambling

At the moment, there is no single conceptual theoretical model of gambling that adequately accounts for the multiple biological, psychological and ecological variables contributing to the development of pathological gambling. Advances in this area are hampered by imprecise definitions of pathological gambling, failure to distinguish between gambling problems and problem gamblers and a tendency to assume that pathological gamblers form one, homogeneous population with similar psychological principles applying equally to all members of the class. The purpose of this paper is to advance a pathways model that integrates the complex array of biological, personality, developmental, cognitive, learning theory and ecological determinants of problem and pathological gambling. It is proposed that three distinct subgroups of gamblers manifesting impaired control over their behaviour can be identified. These groups include (a) behaviourally conditioned problem gamblers, (b) emotionally vulnerable problem gamblers and (c) antisocial, impulsivist problem gamblers. The implications for clinical management are discussed.

Pathological gamblers, with and without substance use disorders, discount delayed rewards at high rates

Pathological gambling is classified as a disorder of impulse control, yet little research has evaluated behavioral indices of impulsivity in gamblers. The rates at which rewards delayed in time are subjectively devalued may be a behavioral marker of impulsivity. This study evaluated delay discounting in 60 pathological gamblers and 26 control participants. Gamblers were divided into those with (n = 21) and without (n = 39) substance use disorders. A hypothetical $1,000 reward was delayed at intervals ranging from 6 hr to 25 years, and immediate rewards varied from $1 to $999. Pathological gamblers discounted delayed rewards at higher rates than control participants, and gamblers with substance use disorders discounted delayed rewards at higher rates than non-substance-abusing gamblers. These data provide further evidence that rapid discounting of delayed rewards may be a feature central to impulse control and addictive disorders, including pathological gambling.