Working memory and affective decision-making in addiction: A neurocognitive comparison between heroin addicts, pathological gamblers and healthy controls
ABSTRACT Cognitive deficits are observed both in heroin dependence and in pathological gambling (PG) on various tasks. PG, as a non-substance addiction, is free of toxic consequences of drug use. Therefore a direct neurocognitive comparison of heroin addicts and pathological gamblers helps dissociate the consequences of chronic heroin use on cognitive function from the cognitive vulnerabilities that predispose addiction.
A case-control design was used, comparing 58 abstinent heroin addicts, 58 pathological gamblers, and 60 healthy controls on working memory and affective decision-making functions. Working memory was assessed using the Self-ordered Pointing Test (SOPT). Affective decision-making was measured by the Iowa Gambling Task (IGT).
Heroin addicts performed significantly worse both on the IGT and on the SOPT, compared to healthy controls. Pathological gamblers performed worse on the IGT than healthy controls, but did not differ from controls on the SOPT. Years of heroin use were negatively correlated with working memory and affective decision-making performance in heroin addicts, while severity of gambling was not significantly correlated with any task performance in pathological gamblers.
Our findings indicate that deficits in affective decision-making shared by heroin dependence and PG putatively represent vulnerabilities to addiction and that working memory deficits detected only in heroin addicts may be identified as heroin-specific harmful effects.
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ABSTRACT: Previous studies by questionnaires have demonstrated that lottery gamblers who have not meet the criteria of pathological gambler show greater gambling acceptability. However, few empirical evidence of whether such nonpathological lottery gamblers (NPLGs) display the same impairments of decision making with pathological gamblers has been found so far. In present study, NPLGs and matched controls (MCs) were asked to perform the Iowa Gambling Task (IGT) and inter-temporal choice task (ICT). We found that compared to MCs, NPLGs displayed much lower IGT scores, net gains and proportions of advantageous decks in the IGT task and much higher percentages of trials during which smaller-but-sooner rewards were chosen in the ICT. These findings indicate that NPLGs display much more risky and impulsive decision makings, just like pathological gamblers in the previous studies. Next, the Go/NoGo task was employed to explore the role of response inhibition in the impairment of decision making in NPLGs. We found that NPLGs did show much higher commission errors compared to MCs. Moreover, IGT scores, net gain and proportions of advantageous decks were significantly negatively correlated with commission errors, which indicates that poor response inhibition might be involved in the impairments of decision making in NPLGs. To our knowledge, we provided the first empirical evidence of impairment of decision making and its cognitive mechanisms in NPLGs.Journal of Gambling Behavior 10/2014; DOI:10.1007/s10899-014-9509-7 · 1.28 Impact Factor
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ABSTRACT: ABSTRACT Background: Cannabis and opioid use are associated with cognitive impairment, whether pre-existing or substance-induced, but there have been few substance-specific assessments of cognitive functioning in adolescent substance users. Working memory impairment may be particularly important as it has been linked to poorer performance in substance abuse treatment. Methods: Working memory (Wechsler Intelligence Scale for Children-IV or Adult Intelligence Scale-IV) and baseline substance use were assessed in 42 youth (mean age = 17.9 years; SD = 1.3; range 16-20; 65% Caucasian, 30% female) 1-2 weeks after admission to residential treatment with supervised abstinence, 19 for primary cannabis dependence, and 23 for primary opioid dependence. Results: There were substantial deficits in working memory in both groups, with significant differences (p < .001) between the opioid (M = 39.1%ile; SD = 25.6) and cannabis groups (M = 16.3%ile; SD = 13.6). The primary opioid group had high rates of cannabis use, with no significant difference in past month days of cannabis use from the primary cannabis group. The opioid group was older and had completed more years of formal education. Seventy-nine percent of the cannabis group had public healthcare coverage (mostly Medicaid) compared to 24% of the opioid sample. Conclusions: Working memory impairment was substantial in treatment-seeking youth with primary cannabis- and opioid-dependence (the latter actually having comparable rates of cannabis use), and significantly more pronounced in the primary cannabis-dependent group. Without an assessment of working memory prior to substance exposure the differential contributions of substance-induced vs. pre-existing impairment are unclear. Lower scores in the cannabis group may reflect lower socioeconomic status (SES), which is typically correlated with cognitive performance. These findings highlight under-recognized cognitive impairment in youth with SUDs, especially inner-city cannabis-dependent youth. Modification of treatments to account for cognitive capacity and/or cognitive remediation interventions may be indicated to improve treatment outcomes.Substance Abuse 08/2014; 35(4). DOI:10.1080/08897077.2014.954027 · 1.62 Impact Factor
04/2014; 6(4):438-446. DOI:10.5455/cap.20140115123942