Interaction Between Family History of Alcoholism and Locus of Control in the Opioid Regulation of Impulsive Responding Under the Influence of Alcohol

Department of Psychology and Neuroscience, University of Colorado, Boulder, Colorado, USA.
Alcoholism Clinical and Experimental Research (Impact Factor: 3.31). 05/2011; 35(11):1905-14. DOI: 10.1111/j.1530-0277.2011.01535.x
Source: PubMed

ABSTRACT Naltrexone (NTX) is an opioid antagonist indicated for the treatment of alcoholism, which is not universally effective. Thus, identifying individual predictors of NTX's behavioral effects is critical to optimizing its therapeutic use. Moreover, given the high rate of relapse during treatment for alcoholism, understanding NTX's behavioral effects when combined with moderate ethanol intake is important. Our previous study of abstinent alcoholics and control subjects showed that a more internal Locus of Control score predicted increased impulsive choice on NTX (Mitchell et al., 2007, Neuropsychopharmacology 32:439-449). Here, we tested whether this predictive relationship remains in the context of moderate alcohol intake.
In this study, we tested the effect of acute NTX (50 mg) on impulsive choice, motor inhibition, and attentional bias after ingestion of moderate ethanol (∼0.3 g/kg, n = 30 subjects). Subjects included those recruited from a pool of ∼1,200 UC Berkeley undergraduates on the basis of scores on the Barratt Impulsiveness Scale (BIS).
Impulsive choice was positively correlated with breath alcohol concentration in placebo sessions. Locus of Control was again the sole predictor of NTX's effect on decision making among subjects with a family history of alcoholism. We also found a weak interaction between BIS scores and NTX's effect on impulsive choice.
Our results reinforce the predictive relationship between Locus of Control and NTX's effect on decision making in those with a family history of alcoholism, suggesting a possible biological basis to this relationship.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A variety of evidence suggests that, among humans, the individual tendency to choose immediate rewards ("Now") over larger, delayed rewards ("Later"), or Now bias, varies with frontal dopamine (DA) levels. As cyclic elevations in estradiol (E+) modulate other frontal DA-dependent behaviors, we tested ovarian cycle effects on Now bias, and whether any such effects are E+ mediated. To do so, we quantified Now/Later choice behavior in naturally cycling adult females (n = 87; ages 18-40 years) during both the menstrual phase (MP; cycle day 1-2; low E+), and the follicular phase (FP; cycle day 11-12; high E+). Now bias decreased an average of 3.6% from MP to FP (p = 0.006). Measures of salivary E+ levels at each visit were available in a subsample of participants (n = 34). Participants with a verified E+ rise from MP to FP showed significantly greater decreases in Now bias at mid-cycle (n = 23) than those without a rise (n = 11; p = 0.03); Now bias decreased an average of 10.2% in the E+ rise group but increased an average of 7.9% in the no E+ rise group. The change in Now bias from MP to FP inversely correlated with the change in E+ (ρ = -0.39; p = 0.023), an effect driven by individuals with putatively lower frontal DA based on genotype at the Val(158)Met polymorphism in the COMT gene. This is the first demonstration that intertemporal choice varies across the ovarian cycle, with Now bias declining at mid-cycle, when fertility peaks. Moreover, our data suggest that the interacting effects of estradiol and frontal DA mediate this cycle effect on decision making.
    The Journal of Neuroscience : The Official Journal of the Society for Neuroscience 04/2014; 34(16):5468-76. DOI:10.1523/JNEUROSCI.0014-14.2014 · 6.75 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We review interventions with empirical support for reducing alcohol use and enhancing self-control. Although any intervention that reduces drinking could improve self-control, we focus here on interventions with evidence of direct benefit for both indications. Although no intervention yet has strong evidence for dual efficacy, multiple interventions have strong evidence for one indication and solid or suggestive evidence for the other. Among pharmacotherapy, opioid antagonists currently have the best evidence of efficacy at reducing alcohol use and enhancing self-control. Nicotinic partial agonist varenicline also seems to be efficacious for alcohol use and self-control. Many psychosocial and behavioral interventions (e.g. cognitive behavioral therapy, contingency management, mindfulness training) may have efficacy for both indications, on the basis of purported mechanisms of action and empirical evidence. Cognitive bias modification and neurophysiological interventions have promise for alcohol use and self-control, and warrant further research. We offer several other suggestions for future research.
    03/2014; 1(1). DOI:10.1007/s40429-013-0008-1
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This study examined differences in the clinical and treatment-related features of pathological gambling (PG) on the basis of the age of PG onset among pathological gamblers who sought treatment. A total of 702 male outpatients with a primary diagnosis of PG and who were treated in a clinical practice were assessed by retrospective chart review. We selected the age of 25 years and younger as the threshold for "group 1." We then stratified the participants into 4 groups on the basis of the age of PG onset in 10-year intervals. Analysis of covariance with a covariant of age and the Pearson χ test were used for analyses. We found that the earlier-onset gamblers were less likely to be escape type (P < 0.05), used significantly more Internet-based gambling (P < 0.001), and were less likely to engage in nonstrategic gambling (P < 0.05) than the later-onset gamblers. In addition, the earlier-onset gamblers took anticraving medication, such as naltrexone, significantly more often (P < 0.05), and sought treatment significantly more slowly after the onset of PG than the later-onset group (P < 0.01). Regarding adherence to treatment, however, there was no significant difference among the 4 groups on the basis of the age of PG onset. The age of PG onset is associated with several important clinical and treatment features. More studies are needed to advance prevention and treatment strategies for each age group.
    Journal of Addiction Medicine 04/2014; 8(3). DOI:10.1097/ADM.0000000000000031 · 1.71 Impact Factor

Full-text (2 Sources)

Available from
May 30, 2014