Background: We investigated (1) the effects of acute alcohol on inhibition of alcohol-related versus neutral cues, (2) the effects of drinking status on inhibition of alcohol-related versus neutral cues, and (3) the similarity of any effects of alcohol or drinking status across two different cue types (lexical versus pictorial).<br/>Methods: Participants received 0.0 g/kg, 0.4 g/kg or 0.6 g/kg of alcohol in a between-subjects design. Healthy, heavy and light social alcohol users (n = 96) completed both lexical and pictorial cue versions of an alcohol-shifting task. Participants were instructed to respond to target stimuli by pressing the spacebar, but to ignore distracter stimuli. Errors towards distracter stimuli were analysed using a series of mixed-model ANOVAs, with between-subjects factors of challenge and drinking status and within-subjects factors of distracter type (alcohol, neutral) and block (shift, non-shift).<br/>Results: Lexical commission error data indicated a main effect of distracter (F [1,90] = 43.25, p<0.001, eta(2) = 0.33), which was qualified by a marginal interaction with challenge condition (F [2,90] = 2.77, p = 0.068, eta(2) = 0.06). Following an acute high dose of alcohol participants made more errors towards alcohol distracters Pictorial commission error data indicated a significant main effect of distracter (F [1,90] = 67.40, p<0.001, eta(2) = 0.43), such that all participants made more errors towards neutral image distracters versus alcohol distracter images.<br/>Conclusions: Our results reveal acute alcohol's impairment of inhibitory control may be enhanced when a response towards alcohol-related lexical stimuli is required to be withheld. (C) 2012 Elsevier Ireland Ltd. All rights reserved.

<a name="Abs1"></a>In the Go/NoGo task, the P3 component of the event-related potential elicited by NoGo stimuli is topographically anterior to that from Go stimuli. This anteriorisation has been linked to the response inhibition thought to be required when NoGo stimuli are presented, and suggested as an index of inhibition. We report a preliminary investigation of this question from an orienting reflex (OR) perspective, in which the autonomic skin conductance response (SCR) was used as an OR &#8220;yardstick&#8221;. We presented subjects with a random mix of 15 target and 15 non-target auditory stimuli with a short inter-stimulus interval, and explored the sources of the resultant P3s using low-resolution electromagnetic tomography (LORETA). Across-subject mean SCRs showed exponential decrement over trials and a larger response to targets, as expected from the OR perspective. LORETA analysis of the across-subject mean initial P3s showed exponential response decrement of their common sources, suggestive of the Novelty P3. Grand mean P3s to targets and non-targets appeared to correspond to the P3b and P3a, respectively. These results suggest that anteriorisation of the P3 to NoGo stimuli may reflect processing related to the basic involuntary OR to indifferent (non-significant) stimuli rather than an active inhibitory process.

This study aimed to replicate findings that alcohol consumption and positive implicit beer-related cognitions can be reduced using inhibitory control (IC) training, with the addition of an active training control. Frontal EEG asymmetry, an objective psychophysiological index of approach motivation, was used as a dependent measure to examine training outcomes. Participants were randomly assigned to one of two IC training conditions (Beer NoGo or Beer Go) or a Brief Alcohol Intervention (BA!) (i.e. the active training control). The IC training tasks consistently paired a stimulus that required a response with images of water (Beer NoGo) or images of beer (Beer Go). Alcohol consumption and implicit beer-related cognitions were measured at pre-training, post-training and at one week follow-up. Frontal EEG asymmetry was recorded during a passive image viewing task that presented neutral, healthy, and beer stimuli - at pre-training, post-training and follow-up. Participants in the Beer NoGo and BAI conditions consumed less beer in a taste test immediately after training than Beer Go participants, suggesting that IC training may be as effective as the already established BAI. The taste test findings were in line with the frontal EEG asymmetry data, which indicated that approach motivation for beer stimuli was altered in the expected directions. However, the positive correlation between post-training frontal EEG asymmetry data and taste test consumption was not significant. While there were no significant changes in implicit beer-related cognitions following training, a trending positive relationship between implicit beer-related cognitions at post-training and taste test consumption was reported. Further exploration addressing the limitations of the current study is required in order to clarify the implications of these findings. (C) 2013 Elsevier B.V. All rights reserved.

Reactivity to smoking-related cues may be an important factor that precipitates relapse in smokers who are trying to quit. The neurobiology of smoking cue reactivity has been investigated in several fMRI studies. We combined the results of these studies using activation likelihood estimation, a meta-analytic technique for fMRI data. Results of the meta-analysis indicated that smoking cues reliably evoke larger fMRI responses than neutral cues in the extended visual system, precuneus, posterior cingulate gyrus, anterior cingulate gyrus, dorsal and medial prefrontal cortex, insula, and dorsal striatum. Subtraction meta-analyses revealed that parts of the extended visual system and dorsal prefrontal cortex are more reliably responsive to smoking cues in deprived smokers than in non-deprived smokers, and that short-duration cues presented in event-related designs produce larger responses in the extended visual system than long-duration cues presented in blocked designs. The areas that were found to be responsive to smoking cues agree with theories of the neurobiology of cue reactivity, with two exceptions. First, there was a reliable cue reactivity effect in the precuneus, which is not typically considered a brain region important to addiction. Second, we found no significant effect in the nucleus accumbens, an area that plays a critical role in addiction, but this effect may have been due to technical difficulties associated with measuring fMRI data in that region. The results of this meta-analysis suggest that the extended visual system should receive more attention in future studies of smoking cue reactivity. (C) 2011 Elsevier Inc. All rights reserved.

Low sensitivity to the acute effects of alcohol is a risk factor for heavy drinking and related problems. However, little research has tested process explanations for such effects. The current study tested the hypothesis that low sensitivity is associated with automatic approach biases for alcohol cues, coupled with deficits inhibiting responses in the presence of such cues. Eighty-five participants varying in alcohol sensitivity completed an Alcohol-Approach Avoidance Task and a Cued Go/No-Go Task while event-related potentials were recorded. Low sensitivity (LS) individuals showed evidence of automatic approach tendencies toward alcohol cues in both tasks, and experienced deficits inhibiting prepotent responses cued by alcohol images. Additionally, the event-related potential data indicated that LS individuals experienced more conflict when attempting to inhibit alcohol-cued responses, but not nonalcohol-cued responses, compared with their high-sensitivity counterparts. Together, these data indicate that alcohol cues elicit an approach bias among LS individuals, translating into greater difficulty inhibiting behavioral responses in the presence of such cues, a pattern generally supportive of dual process models of substance use.

Aims Previous research has shown that consistently not responding to alcohol-related stimuli in a go/no-go training procedure reduces drinking behaviour. This study aimed to examine further the mechanisms underlying this go/no-go training effect. Design, setting and participants Fifty-seven heavy drinkers were assigned randomly to two training conditions: in the beer/no-go condition, alcohol-related stimuli were always paired with a stopping response, while in the beer/go condition participants always responded to alcohol-related stimuli. Participants were tested individually in a laboratory at Maastricht University. Measurements Weekly alcohol intake, implicit attitudes towards beer, approachavoidance action tendencies towards beer and response inhibition were measured before and after the training. Findings Results showed a significant reduction in both implicit attitudes (P = 0.03) and alcohol intake (P = 0.02) in the beer/no-go condition, but not in the beer/go condition. There were no significant training effects on action tendencies or response inhibition. Conclusions Repeatedly stopping pre-potent responses towards alcohol-related stimuli reduces excessive alcohol use via a devaluation of alcohol-related stimuli rather than via increased inhibitory control over alcohol-related responses.

According to dual-process models, excessive alcohol use emerges when response inhibition ability is insufficient to inhibit automatic impulses to drink alcohol. This study examined whether strengthening response inhibition for alcohol-related cues decreases alcohol intake. Fifty-two heavy drinking students were randomly assigned to one of two conditions: In the beer/no-go condition, participants performed a go/no-go task that consistently paired alcohol-related stimuli with a stopping response, to increase response inhibition for alcohol-related stimuli. In the beer/go condition, in contrast, participants were always required to respond to alcohol-related stimuli during the go/no-go task. Before and after the go/no-go manipulation, we measured weekly alcohol intake and implicit attitudes toward alcohol. In addition, we measured alcohol consumption during a taste test immediately after the go/no-go manipulation. Following the manipulation, participants in the beer/no-go condition demonstrated significantly increased negative implicit attitudes toward alcohol, and a significant reduction in weekly alcohol intake, while participants in the beer/go condition showed a non-significant increase in implicit positive attitudes toward alcohol and a significant increase in weekly alcohol intake. This study demonstrates that repeatedly stopping prepotent responses toward alcohol-related stimuli can be an effective strategy to reduce excessive alcohol use. (C) 2011 Elsevier Ireland Ltd. All rights reserved.

Training social drinkers to exercise motor inhibitory control leads to a reduction in alcohol consumption. However, it is unclear if participants should attempt to exercise inhibitory control in the presence of alcohol-related cues or if nonspecific inhibition training is equally effective. It is also unclear if comparable effects can be demonstrated by training oculomotor inhibitory control. We trained motor inhibition in the context of a modified stop-signal task (experiment 1) and oculomotor inhibition in the context of a modified antisaccade task (experiment 2) before investigating the influence of these manipulations on alcohol consumption. Results from experiment 1 demonstrated that training motor inhibition in the presence of alcohol-related cues led to reduced ad libitum alcohol consumption in the laboratory but not self-reported drinking in the week after training. These effects were seen in contrast to a control group that received no inhibition training and another control group that was trained to inhibit only in the presence of neutral cues; alcohol consumption did not differ between the latter two groups. In experiment 2, training of oculomotor inhibition in the presence of alcohol-related cues led to slowed eye movements toward target cues on catch trials, but it did not influence the proportion of inhibitory failures and had no influence on alcohol consumption in the laboratory. We conclude that training participants to exercise inhibitory control in the presence of alcohol-related cues can reduce alcohol consumption, but the effects are transient and are only seen when motor, but not oculomotor, inhibition is trained.

Background: Deficient response inhibition (disinhibition) may play a causal role in alcohol abuse, with impaired inhibition occurring prior to, and acting as a risk factor for, subsequent alcohol problems. We experimentally primed either disinhibited or restrained behaviour while participants completed a Stop-Signal task, before examining the effects on alcohol-seeking behaviour.<br/>Methods: Fifty three social drinkers completed a Stop-Signal task following instructions that either emphasised rapid responding at the expense of successful inhibition (Disinhibition group) or vice versa (Restrained group). Subsequent ad lib alcohol-seeking was measured with a bogus taste test.<br/>Results: As predicted, participants in the Disinhibition group consumed more beer during the taste test compared to participants in the Restrained group. Furthermore, within the Restrained group only, correlations indicated that those participants who responded more cautiously during the Stop-Signal task subsequently consumed less beer.<br/>Conclusions: An experimental manipulation of response set during a response inhibition task, emphasising either restrained or disinhibited responding, has a causal influence on alcohol-seeking behaviour in social drinkers. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Alcohol addictive behaviors are associated with a combination of deficits in executive functions, such as a weak response inhibition, and potent automatic appetitive responses to alcohol-related cues. The aim of the present study was to investigate behavioral responses and event-related potentials (ERPs) associated with specific response inhibition for alcohol-related cues. Thirty participants (15 heavy drinkers and 15 light drinkers) took part in the study. Response inhibition was assessed by a classical letter Go/No-go task and by a modified alcohol Go/No-go task. Participants were also classified as high and low alcohol avoiders. Results showed that heavy drinkers made more false alarms in the letter Go/No-go task. In the alcohol Go/No-go task, an absence of N200 amplitude anteriorization was found in heavy drinkers as compared to light drinkers. Participants with a high level of alcohol avoidance exhibited more false alarms, and higher N200 amplitude for the No-go trials as compared to the Go trials for alcohol-related cues. Higher P300 amplitude was observed in low alcohol avoiders for No-go as compared to Go trials. Therefore, a context involving alcohol-related cues disturbed inhibition capacities of high alcohol avoiders. These results suggest that the level of alcohol avoidance must be taken into account in studies investigating alcohol-related cognitive biases. (C) 2014 Elsevier B.V. All rights reserved.

Background: Cocaine users show impaired inhibitory control on cued go/no-go tasks and attention bias to drug-related stimuli in the emotional Stroop task. The results of a previous study suggested that there is a relationship between inhibitory control and attention bias in alcohol drinkers such that the presentation of alcohol-related images as a go cue in a cued go/no-go task significantly impaired inhibitory control compared to neutral images as a go cue. The present study determined the generality of these previous findings by assessing inhibitory control in cocaine users utilizing a modified cued go/no-go task with cocaine or neutral images as the cues.<br/>Methods: Non-treatment seeking cocaine users (N = 30) completed the modified task after completing detailed measures of demographics and drug use. Participants were matched on basic demographic factors and were assigned to groups in which they saw either a cocaine or neutral image as the go cue.<br/>Results: Participants assigned to the cocaine image go cue condition had a significantly higher proportion of inhibitory failures to the no-go target than their counterparts assigned to the neutral cue condition, but there were no group differences on reaction time (i.e., accuracy was not traded for speed).<br/>Conclusions: Cocaine users were less able to inhibit pre-potent responses when a cocaine-related image served as the go cue than when a neutral image served as the go cue, consistent with previous research in alcohol users. The outcomes suggest that cocaine-related cues produce disinhibition, perhaps contributing to the high incidence of relapse or continued cocaine use. (C) 2013 Elsevier Ireland Ltd. All rights reserved.

<h2 class="secHeading" id="section_abstract">Abstract</h2><p id="">FMRI studies of response inhibition consistently reveal frontal lobe activation. Localization within the frontal cortex, however, varies across studies and appears dependent on the nature of the task. Activation likelihood estimate (ALE) meta-analysis is a powerful quantitative method of establishing concurrence of activation across functional neuroimaging studies. For this study, ALE was used to investigate concurrent neural correlates of successfully inhibited No-go stimuli across studies of healthy adults performing a Go/No-go task, a paradigm frequently used to measure response inhibition. Due to the potential overlap of neural circuits for response selection and response inhibition, the analysis included only event-related studies contrasting No-go activation with baseline, which allowed for inclusion of all regions that may be critical to visually guided motor response inhibition, including those involved in response selection. These Go/No-go studies were then divided into two groups: &ldquo;simple&rdquo; Go/No-go tasks in which the No-go stimulus was always the same, and &ldquo;complex&rdquo; Go/No-go tasks, in which the No-go stimulus changed depending on context, requiring frequent updating of stimulus&ndash;response associations in working memory. The simple and complex tasks demonstrated distinct patterns of concurrence, with right dorsolateral prefrontal and inferior parietal circuits recruited under conditions of increased working memory demand. Common to both simple and complex Go/No-go tasks was concurrence in the pre-SMA and the left fusiform gyrus. As the pre-SMA has also been shown to be involved in response selection, the results support the notion that the pre-SMA is critical for selection of appropriate behavior, whether selecting to execute an appropriate response or selecting to inhibit an inappropriate response.</p>

Background: Chronic methamphetamine abuse is associated with cognitive deficits that may impede treatment in methamphetamine-dependent patients. Exposure to methamphetamine-related cues can elicit intense craving in chronic users of the drug, but the effects of exposure to drug cues on cognitive performance in these individuals are unknown. Objectives: This study assessed whether exposure to methamphetamine-related visual cues can elicit craving and/or alter dual task cognitive performance in 30 methamphetamine-dependent subjects and 30 control subjects in the laboratory. Methods: Reaction time, response errors, and inhibition errors were assessed on an auditory Go-No Go task performed by adult participants (total N = 60) while watching neutral versus methamphetamine-related video cues. Craving was assessed with the Within-Session Rating Scale modified for methamphetamine-dependent subjects. Results: Exposure to methamphetamine-related cues elicited craving only in methamphetamine-dependent subjects. Even in the absence of methamphetamine cues, methamphetamine-dependent subjects exhibited slower reaction times and higher rates of both inhibition and response errors than control subjects did. Upon exposure to methamphetamine cues, rates of both response errors and inhibition errors increased significantly in methamphetamine-dependent subjects. Control subjects exhibited no increase in inhibition errors and only slightly increased rates of response errors upon exposure to methamphetamine cues. Response error rates, but not inhibition error rates or reaction times, during methamphetamine cue exposure were significantly associated with craving scores in methamphetamine-dependent subjects. Conclusions and Significance: Methamphetamine-dependent individuals exhibit cognitive performance deficits that are more pronounced during exposure to methamphetamine-related cues. Interventions that reduce cue reactivity may have utility in the treatment of methamphetamine dependence.

<h2 class="secHeading" id="section_abstract">Abstract</h2><p id="">In the present article a theory is outlined that explains why and when behavioral inhibition alters stimulus evaluations. In addition, some initial evidence is presented that supports the theory. Specifically, results of three experiments show that refraining from responding to stimuli results in devaluation of these stimuli, but only when these stimuli are positive. These findings suggest automatic behavior-regulation, in terms of devaluation of positive stimuli, in situations in which environmental cues triggering approach (because of the positive valence of the stimulus) run counter to situational demands (cues that elicit behavioral inhibition). Relations of the present research to self-perception, cognitive dissonance, and psychological reactance are discussed.</p>

<h2 class="secHeading" id="section_abstract">Abstract</h2><p id="">The stop-signal paradigm is very useful for the study of response inhibition. Stop-signal performance is typically described as a race between a go process, triggered by a go stimulus, and a stop process, triggered by the stop signal. Response inhibition depends on the relative finishing time of these two processes. Numerous studies have shown that the independent horse-race model of Logan and Cowan [Logan, G.D., Cowan, W.B., 1984. On the ability to inhibit thought and action: a theory of an act of control. Psychological Review 91, 295&ndash;327] accounts for the data very well. In the present article, we review the independent horse-race model and related models, such as the interactive horse-race model [Boucher, L., Palmeri, T.J., Logan, G.D., Schall, J.D., 2007. Inhibitory control in mind and brain: an interactive race model of countermanding saccades. Psychological Review 114, 376&ndash;397]. We present evidence that favors the independent horse-race model but also some evidence that challenges the model. We end with a discussion of recent models that elaborate the role of a stop process in inhibiting a response.</p>

<h2 class="secHeading" id="section_abstract">Abstract</h2><p id="">Numerous studies have documented cognitive impairments and hypoactivity in the prefrontal and anterior cingulate cortices in drug users. However, the relationships between opiate dependence and brain structure changes in heroin users are largely unknown. In the present study, we measured the density of gray matter (DGM) with voxel-based morphometry in 30 lifetime heroin-dependent individuals who had abstained from drug use for 5 months, and 34 healthy participants. The DGM of the prefrontal, temporal and cingulate cortices significantly decreased in heroin addicts relative to the healthy group. Critically, partial correlation analysis, which controlled for age, education and gender factors as well as nicotine use and heroin abstinence duration, showed that the duration of heroin use negatively correlated with the DGM in heroin-dependent individuals. These results provide compelling evidence for structural abnormality in heroin-dependent individuals and further suggest that duration of heroin use is a critical factor leading to brain damage.</p>