Inhibition and impulsivity: Behavioral and neural basis of response control

http://homepages.se.edu/cvonbergen/files/2013/01/Fifty-Years-of-the-Barratt-Impulsivenss-Scale_An-Update-and-Review.pdf

Fifty years of the Barratt Impulsiveness Scale: An update and review

Impulsivity as a vulnerability marker for substance-use disorders: Review of findings from high-risk research, problem gamblers and genetic association studies

Quantitative genetic studies (i.e., twin and adoption studies) suggest that genetic influences contribute substantially to the development of attention deficit hyperactivity disorder (ADHD). Over the past 15 years, considerable efforts have been made to identify genes involved in the etiology of this disorder resulting in a large and often conflicting literature of candidate gene associations for ADHD. The first aim of the present study was to conduct a comprehensive meta-analytic review of this literature to determine which candidate genes show consistent evidence of association with childhood ADHD across studies. The second aim was to test for heterogeneity across studies in the effect sizes for each candidate gene as its presence might suggest moderating variables that could explain inconsistent results. Significant associations were identified for several candidate genes including DAT1, DRD4, DRD5, 5HTT, HTR1B, and SNAP25. Further, significant heterogeneity was observed for the associations between ADHD and DAT1, DRD4, DRD5, DBH, ADRA2A, 5HTT, TPH2, MAOA, and SNAP25, suggesting that future studies should explore potential moderators of these associations (e.g., ADHD subtype diagnoses, gender, exposure to environmental risk factors). We conclude with a discussion of these findings in relation to emerging themes relevant to future studies of the genetics of ADHD.

Candidate gene studies of ADHD: a meta-analytic review.

The Psychology of Fear and Stress, J.A. Gray (Ed.). Cambridge University Press, Cambridge (1987), viii and 422 pp, ISBN 0-521-27098-7

Background: Although many studies have established a close relation between impulsivity and alcohol use disorders, little is known about the role of behavioral impulsivity in the development of these disorders.



Objectives:  To determine the role of 2 laboratory paradigms of impulsivity in the development of alcohol use disorders.



Methods:  Follow-up study carried out with 471 participants diagnosed as heavy drinkers (HD) and followed-up for 4 years. Initially, they were compared with a healthy control group. Assessment of behavioral impulsivity was carried out with the Continuous Performance Test (CPT), and the Stop-Signal Task (SST) assessed behavioral inhibitory control. Differential reinforcement for low-rate responding (DRLR) was used to evaluate the delay reward dimension. The Structured Clinical Interview (SCID-DSM-IV) was used to diagnose alcohol dependence.



Results:  The HD performed worse than the control group in all the behavioral tests of impulsivity. Performance in DRLR was the only behavioral impulsivity test that classified the HD correctly compared to controls. Logistic regression analysis indicated that performance on SST was a significant predictor [odds = 1.52(CI = 1.08–2.31)] of developing alcohol dependence.



Conclusions:  Our results support the relation between behavioral impulsivity and alcohol use disorders. The paradigm related to delay of reward may be a factor associated with the use of alcohol and the incapacity to control inhibition as dependence develops.

The role of behavioral impulsivity in the development of alcohol dependence: A 4-year follow-up study.

Pathological gambling (PG) has been associated to both impulsiveness and attention deficit/hyperactivity disorder (ADHD) in different studies. Our objective was to compare different impulsivity and sustained attention variables, using both behavioural tasks and self-administered questionnaires, in a group of pathological gamblers with a history of childhood ADHD (PG-ADHD; n = 16), a group of pathological gamblers without this history (PG-non-ADHD; n = 39), and a control group (n = 40). As instruments of measure, we used the stop signal task (to evaluate inhibitory control/impulsivity), the differential reinforcement of Low Rate Responding Task (delay of gratification/impulsivity) and the Continuous Performance Test (sustained attention). The Barratt Impulsivity Scale (BIS-11) was used as a self-administered questionnaire to measure impulsiveness. Our results show that patients in the PG-ADHD group exhibit a significantly lower capacity to delay gratification than those in the PG-non-ADHD and control groups, and less inhibitory control than patients in the PG-non-ADHD group. On self-administered questionnaires such as the BIS-11 the PG-ADHD group obtained higher scores than the PG-non-ADHD and control groups. However, no differences were found with respect to sustained attention using the CPT. Our results suggest a possible selective implication of the prefrontal cortex in PG, which would be especially evident in those with a childhood history of ADHD.

Impulsivity and Sustained Attention in Pathological Gamblers: Influence of Childhood ADHD History

Background/Rationale: Impulsivity has been associated with alcohol dependence, but impulsivity in alcohol-dependent subjects with a Cluster-B personality disorder (PD) has not been well characterized. Using a variety of laboratory measures of impulsivity, we assessed whether alcohol-dependent patients (ADP) with borderline personality disorder (BPD) exhibited the same pattern of behavioral impulsivity than ADP with antisocial personality disorder (AntPD). Also, differences between ADP without PDs and healthy controls were assessed.



Methods:  A cross-sectional patient survey with a community comparison group. Diagnoses were made using the Structured Interview for DSM-IV. Sustained attention and rapid-response impulsivity were assessed using the continuous performance test. Inhibitory control was measured by the stop-signal task. Ability to delay reward task was assessed using differential reinforcement for low-rate responding (DRLR). A final sample of 247 males with alcohol-dependence recruited from 2 alcoholism treatment centers was compared with a matched nonsubstance-abusing comparison group (n = 96).



Results:  Alcohol-dependent patients with BPD made more omission errors than ADP with AntPD, but individuals with AntPD exhibited the poorest efficiency in DRLR. ADPs with a Cluster-B PD displayed more impairment across all behavioral measures than ADP without PD and than controls. In contrast, with respect to controls ADP without a Cluster-B PD showed more impairment only in DRLR.



Conclusions:  Our findings support the suggestion of 2 paradigms in alcohol dependence. The first, based on inability to delay gratification, might be a vulnerability marker for alcohol dependence. The second was related to inhibitory control and might be specific for AntPD and BPDs.

Varieties of Impulsivity in Males With Alcohol Dependence: The Role of Cluster‐B Personality Disorder

Modulation of impulsivity by topiramate: Implications for the treatment of alcohol dependence

The TaqIA1 allele of the dopamine receptor gene D2 (DRD2) has been associated with alcoholism, as well as with other addictive behaviours. The exact nature of how the presence of this allele can be a vulnerability factor in the development of alcoholism remains unclear. In this study we found that the presence in the DRD2 genotype of the TaqIA1 allele in Spanish alcoholics is associated with higher levels of urine homovanillic acid (HVA) when compared to patients homozygous for the TaqIA2 allele. A sample of 142 Spanish male alcoholic patients was split into 2 groups on the basis of the presence or absence of the A1 allele in their genotype. The urine sample was analyzed by high performance liquid cromatography (HPLC), and the concentration of homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA) and vanilylmandelic acid (VMA) was determined. We found a statistical difference in the concentration of HVA between the groups, that suggests this polymorphism could be related to the variance of urine HVA levels.

M. Jiménez

Papers

The role of behavioral impulsivity in the development of alcohol dependence: A 4-year follow-up study.

Impulsivity and Sustained Attention in Pathological Gamblers: Influence of Childhood ADHD History

Varieties of Impulsivity in Males With Alcohol Dependence: The Role of Cluster‐B Personality Disorder

Modulation of impulsivity by topiramate: Implications for the treatment of alcohol dependence

IDRD2 TaqIA polymorphism is associated with urinary homovanillic acid levels in a sample of Spanish male alcoholic patients.