Is (poly-) substance use associated with impaired inhibitory control? A mega-analysis controlling for confounders.

Many studies have reported that heavy substance use is associated with impaired response inhibition. Studies typically focused on associations with a single substance, while polysubstance use is common. Further, most studies compared heavy users with light/non-users, though substance use occurs along a continuum. The current mega-analysis accounted for these issues by aggregating individual data from 43 studies (3610 adult participants) that used the Go/No-Go (GNG) or Stop-signal task (SST) to assess inhibition among mostly "recreational" substance users (i.e., the rate of substance use disorders was low). Main and interaction effects of substance use, demographics, and task-characteristics were entered in a linear mixed model. Contrary to many studies and reviews in the field, we found that only lifetime cannabis use was associated with impaired response inhibition in the SST. An interaction effect was also observed: the relationship between tobacco use and response inhibition (in the SST) differed between cannabis users and non-users, with a negative association between tobacco use and inhibition in the cannabis non-users. In addition, participants' age, education level, and some task characteristics influenced inhibition outcomes. Overall, we found limited support for impaired inhibition among substance users when controlling for demographics and task-characteristics.

Neuroticism and Negative Urgency in Problematic Alcohol Use: A Pilot Study.

BACKGROUND: Problematic alcohol use is common among university students and personality might account for individual differences in developing this maladaptive behavior. Two personality dispositions implicated in problematic alcohol use are negative urgency and neuroticism. However, the relationship of these traits to problematic alcohol use is unclear. In college students high neuroticism is not directly linked to problematic alcohol use. On the other hand, the experience of emotional distress in people high in neuroticism could impair the capacity for impulse control. Loss of impulse control under conditions of negative affect could trigger impulsive drinking and problematic alcohol use in the long run. OBJECTIVES: We investigated this idea by testing whether negative urgency mediates the relationship of neuroticism to problematic alcohol use. METHODS: Participants were 60 undergraduate university students who completed the Urgency subscale of the Urgency, (lack of) Premeditation, (lack of) Perseverance, Sensation Seeking, and Positive Urgency Impulsive Behaviour scale (UPPS-P), the Alcohol Use Disorders Identification Test (AUDIT), and the Neuroticism subscale of the Eysenck Personality Questionnaire Revised short form (EPQ-RSS). RESULTS: The results confirmed our hypothesis as we found an indirect effect of negative urgency on the relationship between neuroticism and problematic alcohol use. CONCLUSIONS/IMPORTANCE: It appears that it is not distress but the tendency to act rashly when distressed that is important in developing problematic alcohol drinking in university students.

Cue reactivity during treatment, and not impulsivity, predicts an initial lapse after treatment in alcohol use disorders.

Both cue-elicited craving and impulsivity have been involved in alcohol misuse. However, their role in relapse has not been very clear. In the present study, we ask whether cue-elicited craving, impulsivity, and their interaction term predict a lapse in problem drinkers. Participants (n=20) were former patients of the clinic, U-Center, in the Netherlands, who had completed a six-week alcohol treatment program and had an abstinence goal. While in treatment, they underwent a cue exposure paradigm in a real alcohol-related setting and their trait impulsivity was measured with the Barratt Impulsiveness Scale version 11 (BIS-11). During the follow-up assessment, patients were contacted again and asked about their alcohol drinking behavior during the first three months after the end of the treatment program. It was found that higher craving and lower trait impulsivity levels are associated with a higher probability of a lapse.

Dissection of appetitive conditioning. Does impulsivity play a role?

RATIONALE: It is generally assumed that cue-reactivity results from appetitive pavlovian learning. This is the reason for applying cue exposure with response prevention interventions in the treatment of substance and eating disorders. However, not all appetitive conditioned responses are equally sensitive to extinction. Additionally, impulsivity traits appear to moderate cue-reactivity. Nevertheless, there has been little research on the role of impulsivity traits in the learning of different appetitive response systems. OBJECTIVES: The purpose of the present study was (i) to replicate Van Gucht et al.'s (2010) findings, in particular, the acquisition and the differential extinction of appetitive learned responses and ii) to investigate the role of impulsivity traits in appetitive learning. METHODS: Participants (n=50) took part in a single laboratory session. Impulsivity traits (reward sensitivity, response inhibition, sensation seeking) were measured at the beginning of the session. A paradigm similar to Van Gucht et al.'s (2010) was used for the acquisition and extinction of subjective conditioned responses for milk chocolate (craving, expectancy, and liking). RESULTS: The acquisition of appetitive responses was successful. Unlike craving and liking, the extinction of expectancy was fully successful. Impulsivity traits played no role in the acquisition and extinction of appetitive conditioning. CONCLUSIONS: The results support the differential sensitivity of different appetitive response systems to extinction. The lack of findings for the role of impulsivity traits in appetitive learning shows that the question of how impulsivity affects appetitive behaviour still remains open. Theoretical and methodological issues and clinical implications of the findings are discussed.

Higher levels of trait impulsiveness and a less effective response inhibition are linked to more intense cue-elicited craving for alcohol in alcohol-dependent patients.

RATIONALE: Cue-elicited craving is a well-researched phenomenon in alcohol literature. However, not all alcohol-dependent people display the same reactivity to alcohol cues. Personality factors such as multiple impulsivity traits may be responsible for individual differences in cue reactivity by modulating its intensity. Nevertheless, there has been a scarcity of empirical studies testing this assumption in alcohol literature. OBJECTIVES: The aim of the present study was to investigate the effects of response inhibition and trait impulsiveness on cue-elicited craving for alcohol in alcohol-dependent drinkers. METHODS: Participants (n = 41) were inpatients of the private clinic U-Center, Netherlands. Alcohol exposure took place in a real bar-restaurant close to the premises of the clinic, and participants were exposed to real alcohol cues. Response inhibition was assessed with the stop-signal task and trait impulsiveness with the Barratt impulsivity scale version 11. RESULTS: The cue exposure was successful as alcohol-dependent patients experienced higher craving for alcohol when exposed to alcohol rather than to neutral cues. Additionally, both response inhibition and trait impulsiveness predicted cue-elicited craving for alcohol. Trait impulsiveness predicted both the absolute craving in the bar-restaurant and the increase in cue-elicited craving during the whole alcohol cue exposure, while response inhibition predicted only the former. CONCLUSIONS: The results clearly implicate both trait impulsiveness and response inhibition in the modulation of cue-elicited craving in alcohol dependence. Theoretical and methodological issues in the findings and their clinical implications in alcohol treatment and relapse are discussed.

The role of impulsivity and perceived availability on cue-elicited craving for alcohol in social drinkers.

RATIONALE: Previous research has demonstrated a role for impulsivity and perceived availability of the substance in cue-elicited craving. However, their effects on cue-elicited craving for alcohol are still ambiguous. Most important is that there has been no empirical evidence for the potential interaction of these factors on alcohol craving. OBJECTIVES: The aim of the present study was to examine the effects of response inhibition and perceived availability on cue-elicited craving for alcohol in social drinkers. METHODS: Participants were light to moderate social drinkers (N = 75) who were exposed to neutral- and alcohol-related stimuli during a single laboratory session. Response inhibition was assessed with the Stop Signal Task. Participants were randomly assigned to one of two perceived availability groups (n = 37, expecting alcohol; n = 38, not expecting alcohol). RESULTS: Overall craving for alcohol was higher in participants who expected alcohol than in those who did not. This finding was statistically significant only in the alcohol condition. Most important is that there was a significant interaction between response inhibition, perceived availability and time on cue-elicited craving. Regardless of the cue type, impulsive people who expected alcohol experience a significant increase in cue-elicited craving relative to impulsive people who did not expect alcohol. This effect was not observed in the non-impulsive groups. CONCLUSIONS: The results clearly show that perceived availability alone and in combination with response inhibition can modulate alcohol cue reactivity. Theoretical explanations and clinical implications of these findings are discussed.

Can't stop the craving: the effect of impulsivity on cue-elicited craving for alcohol in heavy and light social drinkers.

RATIONALE: A robust finding in the alcohol literature is that heavy and alcohol-dependent drinkers show stronger reactions to alcohol-related cues than light drinkers. However, there are individual differences in the degree of cue-elicited craving. Personality factors appear to be involved in cue reactivity and impulsivity is a possible candidate. OBJECTIVES: The aim of the present study was to examine the role of different aspects of impulsivity in heavy drinking and alcohol cue reactivity in social drinkers. METHODS: Participants were heavy (n = 13) and light (n = 29) social drinkers who were exposed to neutral and alcohol-related stimuli during a single laboratory session. Trait impulsivity, response inhibition, and sensitivity to reward were assessed with the Barratt Impulsiveness Scale (BIS-11), the Stop Signal Task, and the Card-Arranging Reward Responsivity Objective Test, respectively. RESULTS: Heavy drinkers scored higher on trait impulsivity (BIS-11) than light drinkers. In addition, heavy drinkers reported elevated levels of craving for alcohol, but both in light and heavy drinkers, craving increased equally after exposure to alcohol cues. Impulsivity appeared to moderate this relation: heavy drinkers with ineffective response inhibition showed more craving to alcohol cues, compared to heavy drinkers with adequate response inhibition. In light drinkers, response inhibition did not influence craving to alcohol cues. CONCLUSIONS: Different aspects of impulsivity are involved in heavy drinking and perhaps motivate alcohol consumption in a variety of ways. Having a deficient response inhibition appears to be a risk factor for heavy drinkers because it is associated with increased craving to alcohol cues.