ORCID Profile
0000-0002-4312-9766
Current Organisation
University of Amsterdam
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Publisher: Cold Spring Harbor Laboratory
Date: 18-01-2019
DOI: 10.1101/524769
Abstract: Attention-deficit hyperactivity disorder (ADHD) has consistently been associated with substance (ab)use, but the nature of this association is not fully understood. In view of preventive efforts, a vital question is whether there are causal effects, from ADHD to substance use and/or from substance use to ADHD. We applied bidirectional Mendelian randomization using summary-level data from the largest available genome-wide association studies (GWASs) on ADHD, smoking (initiation, cigarettes/day, cessation, and a compound measure of lifetime smoking), alcohol use (drinks/week and alcohol use disorder), cannabis use (initiation and cannabis use disorder (CUD)) and coffee consumption (cups/day). Genetic variants robustly associated with the ‘exposure’ were selected as instruments and then identified in the ‘outcome’ GWAS. Effect estimates from in idual genetic variants were combined with inverse-variance weighted regression and five sensitivity analyses were applied (weighted median, weighted mode, MR-Egger, generalized summary-data-based MR, and Steiger filtering). We found strong evidence that liability to ADHD increases likelihood of smoking initiation and also cigarettes per day among smokers, decreases likelihood of smoking cessation, and increases likelihood of cannabis initiation and CUD. In the other direction, there was evidence that liability to smoking initiation and CUD increase ADHD risk. There was no clear evidence of causal effects between liability to ADHD and alcohol or caffeine consumption. We find evidence for causal effects of liability to ADHD on smoking and cannabis use, and of liability to smoking and cannabis use on ADHD risk, indicating bidirectional pathways. Further work is needed to explore causal mechanisms.
Publisher: Elsevier BV
Date: 03-2019
DOI: 10.1016/J.JBTEP.2018.08.010
Abstract: In two experiments, we investigated the effects of Attentional Bias Modification (ABM) on emotion regulation, i.e. the manner in which people influence emotional experiences. We hypothesized that decreases in attentional bias to threat would impair upregulation and improve downregulation of negative emotions, while increases in attentional bias to threat would improve upregulation and impair downregulation of negative emotions. Using the emotion-in-motion paradigm (Experiment 1, N = 60) and the visual search task (Experiment 2, N = 58), we trained participants to attend to either threatening or positive stimuli and we assessed emotion intensity while observing, upregulating, and downregulating emotions in response to grids of mixed emotional pictures. In Experiment 1, the attend positive group reported more positive emotions while merely watching grids of training pictures and the attend threat group showed impaired upregulation of negative affect. In Experiment 2, the attend threat group reported intensified negative emotions for all three instructions, while the attend positive group remained largely stable over time. We cannot unequivocally attribute these changes in emotion regulation to changes in attentional bias, as neither of the experiments yielded significant changes in attentional bias to threat. By showing that attentional bias modification procedures affect the manner in which people deal with emotions, we add empirical weight to the conceptual overlap between attentional bias modification and emotion regulation.
Publisher: Wiley
Date: 19-05-2017
DOI: 10.1111/EJN.13586
Abstract: The present multimodal MRI study advances our understanding of the corticostriatal circuits underlying goal-directed vs. cue-driven, habitual food seeking. To this end, we employed a computerized Pavlovian-instrumental transfer paradigm. During the test phase, participants were free to perform learned instrumental responses (left and right key presses) for popcorn and Smarties outcomes. Importantly, prior to this test half of the participants had been sated on popcorn and the other half on Smarties - resulting in a reduced desirability of those outcomes. Furthermore, during a proportion of the test trials, food-associated Pavlovian cues were presented in the background. In line with previous studies, we found that participants were able to perform in a goal-directed manner in the absence of Pavlovian cues, meaning that specific satiation selectively reduced responding for that food. However, presentation of Pavlovian cues biased choice toward the associated food reward regardless of satiation. Functional MRI analyses revealed that, in the absence of Pavlovian cues, posterior ventromedial prefrontal cortex tracked outcome value. In contrast, during cued trials, the BOLD signal in the posterior putamen differentiated between responses compatible and incompatible with the cue-associated outcome. Furthermore, we identified a region in ventral amygdala showing relatively strong functional connectivity with posterior putamen during the cued trials. Structural MRI analyses provided converging evidence for the involvement of corticostriatal circuits: diffusion tensor imaging data revealed that connectivity of caudate-seeded white-matter tracts to the ventromedial prefrontal cortex predicted responding for still-valuable outcomes and gray matter integrity in the premotor cortex predicted in idual Pavlovian cueing effects.
Publisher: Springer Science and Business Media LLC
Date: 11-2013
DOI: 10.1007/S00213-013-3318-Z
Abstract: Dysregulated alcohol consumption has been attributed to an imbalance between an approach-alcohol action tendency and executive control processes. However, which specific executive control processes are involved is not known. One candidate executive process is interference suppression, which refers to the suppression of task-irrelevant information through the active maintenance of task-relevant information or a cognitive load. The present study aimed to (1) establish whether alcohol action tendency can be inhibited by interference suppression through the use of cognitive loads and (2) to assess whether in idual differences in the degree of interference suppression from cognitive loads is related to in idual differences in the ability to regulate alcohol consumption. Two groups of social drinkers (total N = 58) who differed in their ability to regulate their alcohol consumption completed a novel cognitive load variant of the approach avoidance task (AAT) and an alcohol taste test. Results indicated that (1) there was a relationship between alcohol bias on the AAT and alcohol consumption under low load, but not high load, consistent with the hypothesis that the action tendency would be inhibited through interference suppression, and (2) this effect of load was not modified by drinking group, with both groups demonstrating equivalent ability to inhibit the action tendency. The present findings suggest that alcohol action tendency can be inhibited through interference suppression, and that this is effective even for those that have difficulty regulating their alcohol consumption.
Publisher: JMIR Publications Inc.
Date: 07-07-2021
DOI: 10.2196/28667
Abstract: Alcohol use and anxiety disorders commonly co-occur, resulting in a more severe clinical presentation and poorer response to treatment. Research has shown that approach bias modification (ApBM) and interpretation bias modification (IBM) cognitive retraining interventions can be efficacious adjunctive treatments that improve outcomes for alcohol use and social anxiety, respectively. However, the acceptability, feasibility, and clinical utility of combining ApBM and IBM programs to optimize treatments among comorbid s les are unknown. It is also unclear whether integrating ApBM and IBM within each training session or alternating them between each session is more acceptable and efficacious. This paper describes the protocol for a randomized controlled pilot trial investigating the feasibility, acceptability, and preliminary efficacy of the Re-train Your Brain intervention—an adjunct web-based ApBM+IBM program—among a clinical s le of emerging adults with hazardous alcohol use and social anxiety. The study involves a three-arm randomized controlled pilot trial in which treatment-seeking emerging adults (18-30 years) with co-occurring hazardous alcohol use and social anxiety will be in idually randomized to receive the Re-train Your Brain integrated program, delivered with 10 biweekly sessions focusing on both social anxiety and alcohol each week, plus treatment as usual (TAU ie, the model of care provided in accordance with standard practice at their service n=30) the Re-train Your Brain alternating program, delivered with 10 biweekly sessions focusing on social anxiety one week and alcohol the next week, plus TAU (n=30) or TAU only (n=30). Primary outcomes include feasibility (uptake, follow-up rates, treatment adherence, attrition, and adverse events) and acceptability (system usability, client satisfaction, user experience, and training format preference). Secondary efficacy outcomes include changes in alcohol approach and interpretation biases, social anxiety, and alcohol use (eg, drinks per day, binge drinking, drinking motives, severity of dependence, and cravings). The primary end point will be posttreatment (6 weeks postbaseline), with a secondary end point at 3 months postbaseline. Descriptive statistics will be conducted for primary outcomes, whereas intention-to-treat, multilevel mixed effects analysis for repeated measures will be performed for secondary outcomes. This study is funded from 2019 to 2023 by Australian Rotary Health. Recruitment is expected to be completed by mid-2022 to late 2022, with follow-ups completed by early 2023. This study will be the first to evaluate whether an ApBM+IBM program is acceptable to treatment-seeking, emerging adults and whether it can be feasibly delivered via the web, in settings where it will ultimately be used (eg, at home). The findings will broaden our understanding of the types of programs that emerging adults will engage with and whether the program may be an efficacious treatment option for this comorbidity. Australian New Zealand Clinical Trials Registry ACTRN12620001273976 www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=364131 PRR1-10.2196/28667
Publisher: Wiley
Date: 11-2020
DOI: 10.1111/ACER.14452
Publisher: Wiley
Date: 17-04-2014
DOI: 10.1111/ADB.12143
Abstract: Cocaine addiction involves persistent deficits to unlearn previously rewarded response options, potentially due to neuroadaptations in learning-sensitive regions. Cocaine-targeted prefrontal systems have been consistently associated with reinforcement learning and reversal deficits, but more recent interspecies research has raised awareness about the contribution of the cerebellum to cocaine addiction and reversal. We aimed at investigating the link between cocaine use, reversal learning and prefrontal, insula and cerebellar gray matter in cocaine-dependent in iduals (CDIs) varying on levels of cocaine exposure in comparison with healthy controls (HCs). Twenty CDIs and 21 HCs performed a probabilistic reversal learning task (PRLT) and were subsequently scanned in a 3-Tesla magnetic resonance imaging scanner. In the PRLT, subjects progressively learn to respond to one predominantly reinforced stimulus, and then must learn to respond according to the opposite, previously irrelevant, stimulus-reward pairing. Performance measures were errors after reversal (reversal cost), and probability of maintaining response after errors. Voxel-based morphometry was conducted to investigate the association between gray matter volume in the regions of interest and cocaine use and PRLT performance. Severity of cocaine use correlated with gray matter volume reduction in the left cerebellum (lobule VIII), while greater reversal cost was correlated with gray matter volume reduction in a partially overlapping cluster (lobules VIIb and VIII). Right insula/inferior frontal gyrus correlated with probability of maintaining response after errors. Severity of cocaine use detrimentally impacted reversal learning and cerebellar gray matter.
Publisher: SAGE Publications
Date: 25-07-2017
Abstract: Cannabis exposure, particularly heavy cannabis use, has been associated with neuroanatomical alterations in regions rich with cannabinoid receptors such as the hippoc us in some but not in other (mainly cross-sectional) studies. However, it remains unclear whether continued heavy cannabis use alters hippoc al volume, and whether an earlier age of onset and/or a higher dosage exacerbate these changes. Twenty heavy cannabis users (mean age 21 years, range 18–24 years) and 23 matched non-cannabis using healthy controls were submitted to a comprehensive psychological assessment and magnetic resonance imaging scan at baseline and at follow-up (average of 39 months post-baseline standard deviation=2.4). Cannabis users started smoking around 16 years and smoked on average five days per week. A novel aspect of the current study is that hippoc al volume estimates were obtained from manual tracing the hippoc us on T1-weighted anatomical magnetic resonance imaging scans, using a previously validated protocol. Compared to controls, cannabis users did not show hippoc al volume alterations at either baseline or follow-up. Hippoc al volumes increased over time in both cannabis users and controls, following similar trajectories of increase. Cannabis dose and age of onset of cannabis use did not affect hippoc al volumes. Continued heavy cannabis use did not affect hippoc al neuroanatomical changes in early adulthood. This contrasts with prior evidence on alterations in this region in s les of older adult cannabis users. In young adults using cannabis at this level, cannabis use may not be heavy enough to affect hippoc al neuroanatomy.
Publisher: Elsevier BV
Date: 04-2019
Publisher: Informa UK Limited
Date: 23-10-2015
DOI: 10.1080/02699931.2015.1092418
Abstract: Although attentional bias modification (ABM) can change anxiety, recent studies failed to replicate such effects, possibly because the visual probe ABM failed to induce changes in attentional bias (AB). We investigated whether visual probe ABM generalised to different measures of AB besides the visual probe task (VPT), and thus whether ABM genuinely changes attentional processing. We trained participants (N = 60) to either attend towards or away from angry facial expressions, and we examined training effects on the dot probe task, the exogenous cueing task, and the visual search task. We found a small change in AB in the VPT, but this effect did not transfer to the exogenous cueing task or the visual search task. Our study shows that ABM does not necessarily lead to generalised effects on AB. This finding can be explained by the poor psychometric properties of the AB measures.
Publisher: Proceedings of the National Academy of Sciences
Date: 15-05-2018
Abstract: Left–right asymmetry is a key feature of the human brain's structure and function. It remains unclear which cortical regions are asymmetrical on average in the population and how biological factors such as age, sex, and genetic variation affect these asymmetries. Here, we describe by far the largest-ever study of cerebral cortical asymmetry, based on data from 17,141 participants. We found a global anterior–posterior “torque” pattern in cortical thickness, together with various regional asymmetries at the population level, which have not been previously described, as well as effects of age, sex, and heritability estimates. From these data, we have created an online resource that will serve future studies of human brain anatomy in health and disease.
Publisher: SAGE Publications
Date: 19-09-2017
Abstract: Using data form a 14-day double-blind trial with 48 smokers randomized to either N-acetylcysteine (2400 mg) or placebo, we tested the effect of N-acetylcysteine on glutamate and gamma-aminobutyric acid concentrations in the dorsal anterior cingulate cortex and on smoking cessation. Smoking related behaviors and neurotransmitter concentrations in the dorsal anterior cingulate cortex were assessed before and after treatment. Forty-seven non-smoking males served as baseline controls. Smokers showed higher baseline glutamate but similar gamma-aminobutyric acid concentrations than non-smokers. There were no treatment effects on dorsal anterior cingulate cortex neurotransmitter concentrations, smoking cessation, craving, or withdrawal symptoms. These results confirm glutamate disbalance in smokers, but not efficacy of N-acetylcysteine.
Publisher: Informa UK Limited
Date: 16-03-2021
Publisher: Wiley
Date: 05-10-2018
DOI: 10.1111/ADD.14424
Publisher: Center for Open Science
Date: 05-09-2023
Publisher: Wiley
Date: 13-01-2019
DOI: 10.1111/DESC.12772
Publisher: JMIR Publications Inc.
Date: 10-03-2021
Abstract: lcohol use and anxiety disorders commonly co-occur, resulting in a more severe clinical presentation and poorer response to single-disorder treatments. Research has shown that Approach Bias Modification (ApBM) and Interpretation Bias Modification (IBM) cognitive re-training interventions can be efficacious adjunctive treatments that improve outcomes for alcohol use and social anxiety symptoms, respectively. However, the acceptability, feasibility and clinical utility of combining ApBM and IBM programs to optimise standard treatments among comorbid s les is unknown. It is also unclear as to whether integrating ApBM and IBM within each training session, or alternating them between each session, is more acceptable and efficacious. his paper describes the study protocol for a randomized controlled pilot trial investigating the feasibility, acceptability, and preliminary efficacy of the ‘Re-Train Your Brain’ intervention – an adjunct web-based ApBM+IBM program – among a clinical s le of emerging adults with hazardous alcohol use and social anxiety. he study involves a 3-arm randomized controlled pilot trial in which treatment-seeking emerging adults (18-30 years) with co-occurring hazardous alcohol use and social anxiety disorder symptoms will be in idually randomized to receive: (1) the Re-Train Your Brain ‘integrated’ program, delivered with 10 bi-weekly sessions focusing on both social anxiety and alcohol each week (50:50 ratio), plus treatment as usual (TAU i.e., the model of care provided in accordance with standard practice at their service n=30) (2) the Re-Train Your Brain ‘alternating’ program, delivered with 10 bi-weekly sessions focusing on social anxiety one week and alcohol the next week in an alternating pattern, plus TAU (n=30) or (3) TAU only (n=30). Primary outcomes include feasibility (uptake, follow-up rates, treatment adherence, attrition, adverse events) and acceptability (system usability, client satisfaction, user experience, training format preference). Secondary efficacy outcomes include changes in alcohol approach and interpretation biases, social anxiety symptoms, and alcohol use (e.g., average drinks per day, binge-drinking, alcohol use motives, severity of alcohol dependence, alcohol craving). The primary endpoint will be post-treatment (6 weeks post-baseline), with a secondary endpoint at 3 months post-baseline. Descriptive statistics will be conducted for primary outcomes, while intention-to-treat multi-level mixed effects analysis for repeated measures will be performed for secondary outcomes. he study is funded from 2019―2023 by Australian Rotary Health. Recruitment is expected to be complete by mid―late 2022, with follow-ups completed by early 2023. he study will be the first to evaluate whether an ApBM+IBM program is acceptable to treatment-seeking emerging adults and whether it is feasible to deliver it online, in settings where it will ultimately be used (e.g., at home). The findings will broaden our understanding of the types of programs that emerging adults will engage with, and whether there is preliminary evidence of it being an efficacious treatment option for this comorbidity. ustralian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12620001273976
Publisher: Elsevier BV
Date: 12-2013
DOI: 10.1016/J.ADDBEH.2013.08.011
Abstract: One of the characteristics of people suffering from addictive behaviors is the tendency to be distracted by drug cues. This attentional bias for drug cues is thought to lead to increased craving and drug use, and may draw in iduals into a vicious cycle of drug addiction. In the current study we developed a Dutch version of the cannabis Stroop task and measured attentional bias for cannabis words in a group of heavy cannabis users and matched controls. The classical Stroop task was used as a global measure of cognitive control and we examined the relationship between cognitive control, cannabis-related problems, cannabis craving and cannabis attentional bias. Using our version of the cannabis Stroop task, a group of heavy cannabis users showed attentional bias to cannabis words, whereas a control group of non-users did not. Furthermore, within the group of cannabis users, those who were clinically recognized as dependent showed a stronger attentional bias than the heavy, non-dependent users. Cannabis users who displayed reduced cognitive control (as measured with the classical Stroop task) showed increased session-induced craving. Contrary to expectations, however, cognitive control did not appear to modulate the relationship between attentional bias to cannabis words (cannabis Stroop task) and cannabis dependence. This study confirmed the relationship between cannabis dependence and attentional bias and extends this by highlighting a moderating role for cognitive control, which may make some more vulnerable to craving.
Publisher: S. Karger AG
Date: 2011
DOI: 10.1159/000327682
Abstract: Relapse is the rule rather than the exception in smokers aiming to quit smoking. Recently, evidence has emerged that glutamate transmission plays an important role in relapse. N-acetylcysteine (NAC), a cysteine prodrug, restores glutamate homeostasis and appears to be a potential new treatment for substance dependence. In the current pilot study, the effects of NAC on short-term abstinence of smoking were investigated. Subjects were heavy smokers randomized to receive placebo (n = 12) or NAC 3,600 mg/day (n = 10) in a double-blind fashion during 3.5 days. Subjects were asked to stop smoking and report on nicotine craving, nicotine withdrawal symptoms, and cigarette smoking during treatment. At the end of the treatment, subjects were invited to smoke a cigarette and to rate the rewarding effect of this cigarette. There was no significant effect of NAC on craving (p = 0.23, i d /i = 0.52) and only a statistical trend towards fewer withdrawal symptoms in the NAC condition (p = 0.07, i d /i = 0.80). Interestingly, subjects receiving NAC rated the first cigarette after the abstinence period of 3.5 days as significantly less rewarding than subjects on placebo (p = 0.04, i d /i = 0.85). It is concluded that the results of this pilot study are encouraging and suggest that NAC might be a promising new treatment option for relapse prevention in nicotine dependence.
Publisher: JMIR Publications Inc.
Date: 03-07-2023
Abstract: nternet-based cognitive behavioral interventions (iCBT) are efficacious treatments of depression and anxiety. Yet, it is unknown whether adding human guidance is feasible and beneficial within a large educational setting. o potentially demonstrate: (1) the superiority of two variants of a transdiagnostic iCBT program (human-guided and computer-guided iCBT) over care as usual (CAU) in a large s le of university students, and (2) the superiority of human-guided iCBT over computer-guided iCBT. articipants were students with elevated levels of anxiety and/or depression from a large university in the Netherlands and were randomized to one of three conditions: (1) human-guided (HG) iCBT, (2) computer-guided (CG) iCBT, and (3) CAU. The primary outcome measures were depression (Patient Health Questionnaire, PHQ-9) and anxiety (Generalized Anxiety Disorder scale, GAD-7). Secondary outcomes included substance-related problems (AUDIT-C and DAST-10). Linear mixed models were used to estimate effects of time, treatment group, and their interactions (slopes). The primary research question was whether the three conditions differed in improvement over three time points (baseline, mid-treatment, posttreatment) in terms of depression and anxiety symptoms. Results were analyzed according to the intention-to-treat principle using multiple imputation. Patients were followed exploratively from baseline, to 6 and 12 months. We randomized 801 participants. oth in short-term and long-term analyses, the slopes for the three conditions did not differ significantly in terms of depression and anxiety, although both online interventions were marginally more efficacious than CAU over 6 months (P’s between .023 and .034). All groups showed significant improvement over time (P’s .001). For the secondary outcomes, only significant improvements over time (across, not between groups) were found for drug use. Significant differences were found in terms of adherence, indicating that participants in the HG condition did more sessions than in the CG condition (P = .002). he transdiagnostic iCBT program offers a practical, feasible and efficacious alternative to usual care to tackle mental health problems in a large university setting. There is no indication that human guidance should be preferred over technological guidance. The potential preference of human support also depends on scale of implementation and cost-effectiveness, which need to be addressed in future trials. L7328/NTR7544 (ICTRP)
Publisher: Center for Open Science
Date: 27-10-2023
Publisher: Public Library of Science (PLoS)
Date: 22-01-2014
Publisher: Elsevier BV
Date: 2016
DOI: 10.1016/J.APPET.2015.10.008
Abstract: Adolescents and children are the targets of much food advertising, the majority of which is for unhealthy snacks. Although the effects of advertising on food preferences and consummatory behavior are well documented, our understanding of the underlying mechanisms is still limited. The present study investigates an associative (ideomotor) mechanism by which exposure to rewarding (snack) outcomes may activate behavior that previously resulted in these rewards. Specifically, we used a computerized task to investigate whether exposing adolescents to food pictures directly, or to Pavlovian cues predictive of those food pictures, would bias their subsequent responses towards the presented/signaled food. Furthermore, we assessed whether this effect was particularly pronounced with palatable, high-calorie snacks (crisps and chocolate) relative to low-calorie snacks (tomatoes and cucumber). In two experiments, adolescents learnt that certain key presses would yield particular food pictures - some high calorie and others low calorie - before learning Pavlovian associations between cues (cartoon monsters) and these same food pictures. Subsequently, in a response-priming test, we examined the extent to which the food pictures and Pavlovian cues spontaneously primed the previously associated response. The results show that we replicated, in adolescents, previous demonstrations of ideomotor response priming in adults: food pictures biased responding towards the response that previously yielded them, and this effect transferred to the Pavlovian cues. Furthermore, the priming effect was significantly stronger for high-calorie rewards than for low-calorie. These findings indicate that the ideomotor mechanism plays an important role in the detrimental effect of our obesogenic environment, with its plethora of unhealthy food reminders, on adolescents' food-related choices.
Publisher: Wiley
Date: 28-12-2022
DOI: 10.1111/ADD.16109
Abstract: Substance use disorders (SUD) are associated with cognitive deficits that are not always addressed in current treatments, and this h ers recovery. Cognitive training and remediation interventions are well suited to fill the gap for managing cognitive deficits in SUD. We aimed to reach consensus on recommendations for developing and applying these interventions. We used a Delphi approach with two sequential phases: survey development and iterative surveying of experts. This was an on‐line study. During survey development, we engaged a group of 15 experts from a working group of the International Society of Addiction Medicine (Steering Committee). During the surveying process, we engaged a larger pool of experts ( n = 54) identified via recommendations from the Steering Committee and a systematic review. Survey with 67 items covering four key areas of intervention development: targets, intervention approaches, active ingredients and modes of delivery. Across two iterative rounds (98% retention rate), the experts reached a consensus on 50 items including: (i) implicit biases, positive affect, arousal, executive functions and social processing as key targets of interventions (ii) cognitive bias modification, contingency management, emotion regulation training and cognitive remediation as preferred approaches (iii) practice, feedback, difficulty‐titration, bias modification, goal‐setting, strategy learning and meta‐awareness as active ingredients and (iv) both addiction treatment work‐force and specialized neuropsychologists facilitating delivery, together with novel digital‐based delivery modalities. Expert recommendations on cognitive training and remediation for substance use disorders highlight the relevance of targeting implicit biases, reward, emotion regulation and higher‐order cognitive skills via well‐validated intervention approaches qualified with mechanistic techniques and flexible delivery options.
Publisher: Springer Science and Business Media LLC
Date: 14-01-2019
Publisher: MDPI AG
Date: 16-12-2021
Abstract: Existing tasks assessing substance-related attentional biases are characterized by low internal consistency and test–retest reliability. This study aimed to assess the psychometric properties of a novel dual-probe task to measure alcohol-related attentional bias. Undergraduate students were recruited in June 2019 (N = 63 final N = 57 mean age = 20.88, SD = 2.63, 67% females). In the dual-probe task, participants were presented with simultaneous visual streams of adverts promoting either alcoholic or non-alcoholic drinks, and probes were presented in both streams. The dual-probe task measured the percentage of accurately identified probes that appeared on alcohol adverts in relation to total accuracy. The dual-probe task displayed excellent split-half reliability (M = 0.90, SD = 0.11 α = 0.90 95% CI [0.84, 0.93]), and the derived attentional bias measure was significantly positively associated with beer drinking in a taste-test (r (57) = 0.33, p = 0.013 95% CI [0.07, 0.54]), with habitual drinking (r (57) = 0.27, p = 0.045 95% CI [0.01, 0.49]), and with increased craving (r (57) = 0.29, p = 0.031 95% CI [0.03, 0.51]). Thus, the dual-probe task assessed attentional bias with excellent internal consistency and was associated with laboratory and habitual drinking measures, demonstrating initial support for the task’s utility in addiction research.
Publisher: American Psychological Association (APA)
Date: 2013
DOI: 10.1037/A0029982
Abstract: The inability to regulate alcohol consumption has been attributed to an imbalance between stimulus-driven behavioral biases, or action tendencies, and the ability to exert goal-directed control, or working memory capacity (WMC). Previous research assessing the interaction between these variables has not considered the effect of whether in iduals' current goals or task demands require goal-directed control. Our aim was to examine the potential interaction of appetitive action tendencies and the ability to exert control over these action tendencies as a function of whether task demands require applying control for successful task completion. Two groups of social drinkers (n = 40 per group) who differed in their ability to regulate their alcohol consumption completed a novel variant of the Approach-Avoidance Task (AAT), which separately assessed approach and avoid trials. The approach and avoidance responses differentially require goal-directed control, depending on whether the task-relevant response is incongruent with the stimulus-driven action tendency. Results indicated that (a) group differences in AAT indices were only observed on trials that required an avoidance movement, which are trials where the task-relevant response would be incongruent with an approach action tendency, and (b) the extent of the group differences for these avoidance trials was moderated by in idual differences in WMC, such that problem drinkers with lower WMC showed greater behavioral bias toward alcohol than those with higher WMC. These findings suggest that difficulties in regulating alcohol consumption arise from a complex interaction of action-tendencies, WMC, and current goals or task demands.
Publisher: Springer Science and Business Media LLC
Date: 21-02-2018
Publisher: Informa UK Limited
Date: 02-05-2019
DOI: 10.1080/02699931.2019.1609423
Abstract: Although attentional bias (AB) is considered a key characteristic of anxiety problems, the psychometric properties of most AB measures are either problematic or unknown. We conducted two experiments in which we addressed the reliability, convergent validity, and concurrent validity of different AB measures in unselected student s les. In Experiment 1 (
Publisher: Elsevier BV
Date: 09-2011
DOI: 10.1016/J.JBTEP.2019.03.009
Abstract: Although induced changes in interpretation bias can lead to reduced levels of stress reactivity, results are often inconsistent. One possible cause of the inconsistencies in the effects of interpretation bias modification (IBM) on stress reactivity is the degree to which participants engaged in emotion regulation while being exposed to stressors. In this study, we distinguished between the effects of IBM on natural, unregulated stress reactivity and the effects of IBM on people's ability to up- or downregulate this stress reactivity. Both in the context of general anxiety (Experiment 1, N = 59) and social anxiety (Experiment 2, N = 54), we trained participants to interpret ambiguous scenarios in either a positive or a negative manner, and we assessed the effects on unregulated and regulated stress reactivity. Although we found relatively consistent training-congruent changes in interpretation bias in both experiments, these changes had no effect on either unregulated or regulated stress reactivity. In both experiments, we used healthy student s les and relatively mild emotional stressors. In line with previous research, our findings suggest that the effects of IBM on unregulated stress reactivity may be small and inconsistent. Differences in the extent to which participants engaged in emotion regulation during stressor exposure are unlikely to account for these inconsistencies.
Publisher: Elsevier BV
Date: 11-2015
DOI: 10.1016/J.BRAINRES.2015.02.020
Abstract: Ideomotor theory proposes that goal-directed action emerges from the implicit, incidental acquisition of bi-directional associations between actions and their outcomes. In line with this idea, a simple two-stage priming paradigm has provided evidence that presentation of outcomes primes previously associated actions. In the current study we compare the standard priming paradigm with two actions and two unique outcomes (Experiment 1) with two more complex, but otherwise identical versions (Experiment 2: two vs. four actions with four outcomes). Our results show stronger evidence of action-outcome learning in the simple compared to the more complex versions. We suggest that, when using the classic two-stage paradigm, action-outcome acquisition is limited to just a few action-outcome associations that can be concurrently learned-at least if learning is not supported by discriminative stimuli and outcomes are not salient or motivationally relevant. This article is part of a Special Issue entitled SI: Prediction and Attention.
Publisher: Cold Spring Harbor Laboratory
Date: 31-07-2022
DOI: 10.1101/2022.07.28.22278144
Abstract: Substance use disorders (SUD) are associated with cognitive deficits that are not always addressed in current treatments, and this h ers recovery. Cognitive training and remediation interventions are well suited to fill the gap for managing cognitive deficits in SUD. We aimed to reach consensus on recommendations for developing and applying these interventions. Delphi approach with two sequential phases: survey development and iterative surveying of experts. Online study. During survey development, we engaged a group of 15 experts from a working group of the International Society of Addiction Medicine (Steering Committee). During the surveying process, we engaged a larger pool of experts (n=53) identified via recommendations from the Steering Committee and a systematic review. Survey with 67 items covering four key areas of intervention development, i.e., targets, intervention approaches, active ingredients, and modes of delivery. Across two iterative rounds (98% retention rate), the experts reached a consensus on 50 items including: (i) implicit biases, positive affect, arousal, executive functions, and social processing as key targets of interventions (ii) cognitive bias modification, contingency management, emotion regulation training, and cognitive remediation as preferred approaches (iii) practice, feedback, difficulty-titration, bias-modification, goal setting, strategy learning, and meta-awareness as active ingredients and (iv) both addiction treatment workforce and specialized neuropsychologists facilitating delivery, together with novel digital-based delivery modalities. Expert recommendations on cognitive training and remediation for SUD highlight the relevance of targeting implicit biases, reward, emotion regulation, and higher-order cognitive skills via well-validated intervention approaches qualified with mechanistic techniques and flexible delivery options.
Publisher: Springer Science and Business Media LLC
Date: 23-05-2017
Publisher: Wiley
Date: 20-11-2019
DOI: 10.1111/ADB.12830
Abstract: While imaging studies have demonstrated volumetric differences in subcortical structures associated with dependence on various abused substances, findings to date have not been wholly consistent. Moreover, most studies have not compared brain morphology across those dependent on different substances of abuse to identify substance‐specific and substance‐general dependence effects. By pooling large multinational datasets from 33 imaging sites, this study examined subcortical surface morphology in 1628 nondependent controls and 2277 in iduals with dependence on alcohol, nicotine, cocaine, meth hetamine, and/or cannabis. Subcortical structures were defined by FreeSurfer segmentation and converted to a mesh surface to extract two vertex‐level metrics—the radial distance (RD) of the structure surface from a medial curve and the log of the Jacobian determinant (JD)—that, respectively, describe local thickness and surface area dilation/contraction. Mega‐analyses were performed on measures of RD and JD to test for the main effect of substance dependence, controlling for age, sex, intracranial volume, and imaging site. Widespread differences between dependent users and nondependent controls were found across subcortical structures, driven primarily by users dependent on alcohol. Alcohol dependence was associated with localized lower RD and JD across most structures, with the strongest effects in the hippoc us, thalamus, putamen, and amygdala. Meanwhile, nicotine use was associated with greater RD and JD relative to nonsmokers in multiple regions, with the strongest effects in the bilateral hippoc us and right nucleus accumbens. By demonstrating subcortical morphological differences unique to alcohol and nicotine use, rather than dependence across all substances, results suggest substance‐specific relationships with subcortical brain structures.
Publisher: Elsevier BV
Date: 06-2018
DOI: 10.1016/J.DRUGALCDEP.2018.03.010
Abstract: Neuroimaging studies have demonstrated gray matter (GM) volume abnormalities in substance users. While the majority of substance users are polysubstance users, very little is known about the relation between GM volume abnormalities and polysubstance use. In this study we assessed the relation between GM volume, and the use of alcohol, tobacco, cocaine and cannabis as well as the total number of substances used, in a s le of 169 males: 15 non-substance users, 89 moderate drinkers, 27 moderate drinkers who also smoke tobacco, 13 moderate drinkers who also smoke tobacco and use cocaine, 10 heavy drinkers who smoke tobacco and use cocaine and 15 heavy drinkers who smoke tobacco, cannabis and use cocaine. Regression analyses showed that there was a negative relation between the number of substances used and volume of the dorsal medial prefrontal cortex (mPFC) and the ventral mPFC. Without controlling for the use of other substances, the volume of the dorsal mPFC was negatively associated with the use of alcohol, tobacco, and cocaine. After controlling for the use of other substances, a negative relation was found between tobacco and cocaine and volume of the thalami and ventrolateral PFC, respectively. These findings indicate that mPFC alterations may not be substance-specific, but rather related to the number of substances used, whereas, thalamic and ventrolateral PFC pathology is specifically associated with tobacco and cocaine use, respectively. These findings are important, as the differential alterations in GM volume may underlie different cognitive deficits associated with substance use disorders.
Publisher: Wiley
Date: 05-07-2013
DOI: 10.1111/ADD.12256
Abstract: To assess whether alcohol‐related biases in selective‐attention and action tendency uniquely or concurrently predict the ability to regulate alcohol consumption. Two groups of undergraduate social drinkers (total n = 55) who differed in their ability to regulate their alcohol consumption completed a novel S elective‐ A ttention/ A ction‐ T endency T ask ( SA / ATT ), which assessed separately alcohol‐related biases in selective attention and action tendency. U niversity of W estern A ustralia, A ustralia. Dysregulated drinking was operationalized as a self‐reported high level of alcohol consumption on the Alcohol Consumption Questionnaire, and a high desire to reduce consumption on the Brief Readiness to Change Algorithm. Selective attention and action tendency were assessed using the SA / ATT , working memory was assessed using the operation‐span task and participant characteristics were assessed using the Alcohol Use Disorders Identification Test ( AUDIT) and Stages of Change Readiness and Treatment Eagerness Scale ( SOCRATES) . Results indicated that (i) there was no significant association between alcohol‐related biases in selective attention and action tendency, r = 0.16, P = 0.274, and (ii) biases towards alcohol, in both selective attention, β = 1.01, odds ratio = 2.74, P = 0.022, and action tendency, β = 1.24, odds ratio = 3.45, P = 0.015, predicted independent variance in dysregulated‐drinker status. Biases in selective attention and action tendency appear to be distinct mechanisms that contribute independently to difficulty regulating alcohol consumption. Treatment components that could be combined to target both mechanisms could enhance treatment outcomes for alcohol‐use disorders.
Publisher: Frontiers Media SA
Date: 2012
Publisher: Elsevier BV
Date: 10-2017
DOI: 10.1016/J.DRUGALCDEP.2017.06.025
Abstract: Glutamate and GABA play an important role in substance dependence. However, it remains unclear whether this holds true for different substance use disorders and how this is related to risk-related traits such as impulsivity. We, therefore, compared Glx (as a proxy measure for glutamate) and GABA concentrations in the dorsal anterior cingulate cortex (dACC) of 48 male cigarette smokers, 61 male smoking polysubstance users, and 90 male healthy controls, and investigated the relationship with self-reported impulsivity and substance use. Glx and GABA concentrations were measured using proton Magnetic Resonance Spectroscopy. Impulsivity, smoking, alcohol and cocaine use severity and cannabis use were measured using self-report instruments. Results indicate a trend towards group differences in Glx. Post-hoc analyses showed a difference between smokers and healthy controls (p=0.04) and a trend towards higher concentrations in smoking polysubstance users and healthy controls (p=0.09), but no differences between smokers and smoking polysubstance users. dACC GABA concentrations were not significantly different between groups. Smoking polysubstance users were more impulsive than smokers, and both groups were more impulsive than controls. No significant associations were observed between dACC neurotransmitter concentrations and impulsivity and level and severity of smoking, alcohol or cocaine use or the presence of cannabis use. The results indicate that differences in dACC Glx are unrelated to type and level of substance use. No final conclusion can be drawn on the lack of GABA differences due to assessment difficulties. The relationship between dACC neurotransmitter concentrations and cognitive impairments other than self-reported impulsivity should be further investigated.
Publisher: Proceedings of the National Academy of Sciences
Date: 30-06-2009
Abstract: About 70% of more than half a million Implicit Association Tests completed by citizens of 34 countries revealed expected implicit stereotypes associating science with males more than with females. We discovered that nation-level implicit stereotypes predicted nation-level sex differences in 8th-grade science and mathematics achievement. Self-reported stereotypes did not provide additional predictive validity of the achievement gap. We suggest that implicit stereotypes and sex differences in science participation and performance are mutually reinforcing, contributing to the persistent gender gap in science engagement.
Publisher: Springer Science and Business Media LLC
Date: 11-2018
Publisher: Elsevier BV
Date: 08-2014
DOI: 10.1016/J.APPET.2014.04.005
Abstract: Why do we indulge in food-seeking and eating behaviors at times when we are already fully sated? In the present study we investigated the hypothesis that food-associated cues in the environment can interfere with goal-directed action by eliciting food-seeking that is independent of the current desirability of the outcome. To this end, we used a computerized task in which participants learned to press keys for chocolate and popcorn rewards. Subsequently, we investigated whether satiation on one of these rewards would bias choice toward the other, still desirable, food reward. We found that satiation did indeed selectively reduce responding on the associated key in the absence of food-associated cues. In contrast, in a Pavlovian-instrumental transfer (PIT) test, satiation failed to reduce cue-elicited food-seeking: in line with our hypothesis, cues that had previously been paired with chocolate and popcorn led to increased responding for the signaled food reward, independent of satiation. Furthermore, we show that food-associated cues will not only bias choice toward the signaled food (outcome-specific transfer), but also enhance the vigor of responding generally (general transfer). These findings point to a mechanism that may underlie the powerful control that cues in our obesogenic environment exert over our behavior.
Publisher: Elsevier BV
Date: 11-2016
DOI: 10.1016/J.DRUGALCDEP.2016.09.023
Abstract: Cocaine dependence has been associated with alterations in the brain's white matter integrity, yet relevant questions remain about what alterations are linked to cocaine use and/or polysubstance use, and whether they are amenable to abstinence. This study applied a single measurement session of diffusion tensor imaging (DTI) to examine white matter structure in male cocaine polysubstance users (n=37) versus male healthy controls (n=38), along with correlations between DTI measures and patterns of polysubstance use and duration of abstinence. Specifically, we conducted voxel-wise analyses of fractional anisotropy (FA) in the corpus callosum, frontolimbic, striatal and cingulate tracts relevant to drug sequelae. Cocaine polysubstance users, compared to controls, showed lower FA in the body of the corpus callosum, anterior cingulate, uncinate fasciculus and retrolenticular part of the internal capsule. Duration of cocaine use had a marginal negative association with FA in the corpus callosum, and duration of alcohol use was negatively associated with FA in the internal capsule and the uncinate fasciculus. Duration of cocaine abstinence was positively correlated with FA in the uncinate fasciculus, posterior cingulate and fornix-striatum. In the context of cocaine polysubstance use, chronicity of cocaine use is therefore likely to be associated with lower FA in the corpus callosum, and chronicity of alcohol use with lower FA in the frontal-striatal and frontal-limbic tracts. Longer abstinence was correlated to greater FA in frontal-striatal and frontal-limbic tracts, though the direction of causality remains unclear. Since the results did not survive multiple comparison-corrected thresholds, more studies are needed to confirm these indications.
Publisher: Oxford University Press
Date: 24-05-2018
DOI: 10.1093/OSO/9780190499037.003.0008
Abstract: This chapter discusses dual-process models of (health) behaviors, regarding both their recent criticisms and implications for health interventions. It agrees with critics that impulsive and reflective processes should not be equated with specific brain processes, but that psychological processes are emergent properties of the dynamic unfolding interplay between different neural systems. It maintains that at a psychological level of description, these models can still be useful to understand challenges to health behaviors and possible interventions. Affective processes can influence impulsive decision-making in health, but also reflective processes, when they concern affectively relevant goals. Cognitive training methods, including cognitive bias modification and training of executive control, have shown some success in changing health behaviors, but a critical variable for long-term success appears to be motivation to change.
Publisher: JMIR Publications Inc.
Date: 25-10-2023
DOI: 10.2196/46008
Publisher: Elsevier BV
Date: 06-2017
DOI: 10.1016/J.DRUGALCDEP.2017.01.041
Abstract: The current study examined whether cognitive control moderates the association between (non-drug) reward-modulated attentional capture and use of alcohol and other drugs (AOD). Participants were 66 university students who completed an assessment including questions about AOD use, a visual search task to measure value-modulated attentional capture, and a goal-directed selective attention task as a measure of cognitive control. The association between the effect of value-modulated attentional capture and illicit drug use was moderated by level of cognitive control. Among participants with lower levels of cognitive control, value-modulated attentional capture was associated with illicit drug use. This was not the case among participants with higher levels of cognitive control, who instead showed a significant association between illicit drug use and self-reported impulsivity, as well as alcohol use. These results provide support for models that view addictive behaviours as resulting from interaction and competition between automatic and more reflective processes. That is, the mechanisms that ultimately drive addictive behaviour may differ between people low or high in cognitive control. This has important implications for understanding the development and maintenance of substance use disorders and potentially their treatment and prevention.
Publisher: JMIR Publications Inc.
Date: 25-01-2023
Abstract: nterpretation Bias Modification (IBM) and Approach Bias Modification (ApBM) cognitive re-training interventions can be efficacious adjunctive treatments for improving social anxiety or alcohol use problems. However, previous trials have not examined the combination of these interventions among a young, comorbid s le. his study describes the feasibility, acceptability, and preliminary efficacy of a web-based IBM+ApBM program for young adults with social anxiety and hazardous alcohol use (‘Re-Train Your Brain’), when delivered in conjunction with treatment as usual (TAU). he study involved a 3-arm randomized controlled pilot trial in which treatment-seeking young adults (18-30 years) with co-occurring social anxiety and hazardous alcohol use were in idually randomized to receive: (i) the ‘integrated’ Re-Train Your Brain program, where each session included both IBM and ApBM (50:50 ratio), plus TAU n=35) (ii) the ‘alternating’ Re-Train Your Brain program, where each session focused on IBM or ApBM in an alternating pattern, plus TAU (n=32) or (iii) TAU only (n=33). Primary outcomes included feasibility (consent, follow-up rates, withdrawals, treatment adherence, adverse events) and acceptability (system usability, client satisfaction, training format preference). Secondary efficacy outcomes included changes in cognitive biases (interpretation, alcohol approach, and comorbid social anxiety and alcohol interpretation biases), social anxiety symptoms, and alcohol use (e.g., average drinks per day, hazardous drinking, severity of alcohol dependence, alcohol craving). Assessments were conducted at baseline, post-intervention (6-weeks post-baseline), and 12-weeks post-baseline. Descriptive statistics and linear and logistic regressions were conducted for primary outcomes, while intention-to-treat multi-level mixed effects analysis for repeated measures were performed for secondary outcomes, and reported with their corresponding effect sizes. oth Re-Train Your Brain program formats were feasible and acceptable to young adults. When coupled with TAU, both integrated and alternating programs resulted in greater self-reported improvements than TAU only on anxiety interpretation biases (at 6-week follow-up d=0.80 and d=0.89) and comorbid interpretation biases (at 12-week follow-up d=1.53 and d=1.67). Additionally, the alternating group reported large improvements over control on generalised social anxiety symptoms (at 12-week follow-up d=0.83) and alcohol cravings (at 6-week follow-up d=0.81). There were null effects on all other variables, and no differences between the two intervention groups on efficacy outcomes. hould these findings be replicated in a larger randomized controlled trial, Re-Train Your Brain has the potential to be a scalable, low cost, and non-labour-intensive adjunct intervention for targeting interpretation and comorbidity biases, as well as generalised anxiety and alcohol-related outcomes in the real world. he study was prospectively registered with the Australian New Zealand Clinical Trials Registry (ANZCTR ACTRN12620001273976) and the protocol was published in JMIR: Research Protocols [Prior et al., 2021. JMIR Research Protocols, 10(7):e28667. doi: 10.2196/28667]. R2-10.2196/28667
Publisher: Center for Open Science
Date: 17-04-2023
Publisher: Frontiers Media SA
Date: 13-04-2017
No related grants have been discovered for Reinout Wiers.