Attentional capture by alcohol-related stimuli may be activated involuntarily by top-down search goals

The Continuing Challenges of Studying Parallel Behaviours in Humans and Animal Models

The use of animal models continues to be essential for carrying out research into clinical phenomena, including addiction. However, the complexity of the clinical condition inevitably means that even the best animal models are inadequate, and this may go some way to account for the apparent failures of discoveries from animal models, including the identification of potential novel therapies, to translate to the clinic. We argue here that it is overambitious and misguided in the first place to attempt to model complex, multifacetted human disorders such as addiction in animals, and especially in rodents, and that all too frequently "validity" of such models is limited to superficial similarities, referred to as "face validity", that reflect quite different underlying phenomena and biological processes from the clinical situation. Instead, a more profitable approach is to identify (a) well-defined intermediate human behavioural phenotypes that reflect defined, limited aspects of, or contributors to, the human clinical disorder, and (b) to develop animal models that are homologous with those discrete human behavioural phenotypes in terms of psychological processes, and underlying neurobiological mechanisms. Examples of past and continuing weaknesses and suggestions for more limited approaches that may allow better homology between the test animal and human condition are made.

Dissociation of drug and negative emotional cue induced attentional bias in individuals with methamphetamine-use disorder

BACKGROUND AND OBJECTIVES

Although both drugs and negative emotions can trigger drug craving or relapse in individuals with methamphetamine-use disorder (MUD), it remains unclear whether individuals with MUD have attentional biases toward both drug and negative emotional cues and whether this bias involves attention orientation or difficulty in attention disengagement. This study aimed to measure different components of attentional bias toward drug-related and negative emotional cues in individuals with MUD.

METHODS

Two dot-probe tasks were used to investigate attentional bias toward drug (drug task) and negative emotional cues (emotion task) in individuals with MUD. Forty-three males with MUD (average age of 43.44 ± 11.91 years, average drug-use duration of 11.35 ± 8.39 years) participated in the study voluntarily.

RESULTS

There was a significant interaction between the task type and location (p = .01). Specifically, for drug cues, participants showed significant difficulty in attention disengagement toward drug cues (p = .01); however, no attention orientation (p = .46). For negative emotional cues, neither significant attention orientation (p = .07) nor significant difficulty in attention disengagement (p = .50) was found.

CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE

Attentional bias in individuals with MUD was highly selective for drug cues; thus, difficulty in attention disengagement from drug cues can be considered a potential mediating mechanism for attentional bias modification interventions for individuals with MUD. This study served to generate hypotheses or suggest future experiments on interventions for individuals with MUD.

Don't look now! Emotion-induced blindness: The interplay between emotion and attention

Scientists have long been interested in understanding the influence of emotionally salient stimuli on attention and perception. One experimental paradigm that has shown great promise in demonstrating the effect of such stimuli is emotion-induced blindness. That is, when emotionally salient stimuli are presented in a rapid stream of stimuli, they produce impairments in the perception of task-relevant stimuli, even though they themselves are task irrelevant. This is known as emotion-induced blindness, and it is a profound and robust form of attentional bias. Here, we review the literature on emotion-induced blindness, such as identifying the types of stimuli that elicit it, and its temporal dynamics. We discuss the role of dimensional versus categorical approaches to emotion in relation to emotion-induced blindness. We also synthesize the work examining whether certain individuals, such as those high in anxiety versus psychopathy, succumb to emotion-induced blindness to different extents, and we discuss whether the deficit can be reduced or even abolished. We review the theoretical models that have been proposed to explain the phenomenon. Finally, we identify exciting questions for future research, and elucidate useful frameworks to guide future investigations.

Attentional bias in alcohol drinkers: A systematic review of its link with consumption variables

In severe alcohol use disorder (SAUD), attentional bias refers to the preferential allocation of attentional resources toward alcohol-related cues. Dominant models consider that this bias plays a key role in the emergence and maintenance of SAUD. We evaluate the available experimental support for this assumption through a systematic literature review, providing a critical synthesis of studies exploring the links between alcohol consumption and attentional bias. Using PRISMA guidelines, we explored three databases (PsycINFO, PubMed, Scopus) and extracted 95 papers. We assessed their methodological quality and categorized them based on the population targeted, namely patients with SAUD or subclinical populations with various drinking patterns. We also classified papers according to the measures used (i.e., behavioral or eye-tracking measures). Overall, subclinical populations present an alcohol-related bias, but many studies in SAUD did not find such bias, nor approach/avoidance patterns. Moreover, attentional bias fluctuates alongside motivational states rather than according to alcohol use severity, which questions its stability. We provide recommendations to develop further theoretical knowledge and overcome methodological shortcomings.

Prioritization of personally relevant stimuli in male abstinent heroin users

The prioritization of the processing of highly relevant personal stimuli pervades various cognitive domains and is vital to our survival and normal functioning. However, the extent to which this process is altered by drug addiction remains to be elucidated. The present study examined the self-prioritization effect in abstinent heroin users (AHUs) using the perceptual matching task, which controls for the confounding effect of familiarity, and further modified it to revalidate the drug-prioritization effect (DPE). Eighty male AHUs and forty healthy control (HC) participants were recruited for this study. Participants filled in the questionnaire and completed two perceptual matching tasks. The questionnaire included demographic information (e.g., age, education) and characteristics of drug use, whereas the HC participants only completed the demographic information. AHUs exhibited a robust self-advantage in the self-perceptual matching task, and that the magnitude of the self-prioritization effect (MSPE) was comparable to that in HCs. Only AHUs prioritized the processing of drug-related stimuli in the drug-perceptual matching task, and showed similar prioritization effects during self- and drug-related processing. The MSPE and magnitude of the drug-prioritization effect (MDPE) were correlated with the heroin consumption behavior in AHUs. The process of self-prioritization is intact in drug users, and they uniquely prioritize the processing of drug cues. The similar pattern between the self- and drug-related processing provided behavioral evidence to support that drug cues are likely to be associated with heightened personal relevance in drug users. These prioritization processes may play critical roles in addiction and provide a promising route for intervention.

Faces are not always special for attention: Effects of response-relevance and identity

Research over the past 25 years indicates that stimulus processing is diminished when attention is engaged in a perceptually demanding task of high 'perceptual load'. These results have generalized across a variety of stimulus categories, but a controversy evolved over the question of whether perception of distractor faces (or other categories of perceptual expertise) can proceed irrespective of the level of perceptual load in the attended task. Here we identify task-relevance, and in particular identity-relevance, as a potentially important factor in explaining prior inconsistencies. In four experiments, we tested whether perceptual load in an attended letter or word task modulates the processing of famous face distractors, while varying their task-relevance. Distractor interference effects on task RTs was reduced by perceptual load not only when the faces were entirely task-irrelevant, but also when the face gender was task relevant, within a name gender classification response-competition task, using famous female or male distractor faces. However, when the identity associated with the famous faces was primed by the task using their names, as in prior demonstrations that face distractors are immune to the effects of perceptual load, we were able to replicate these prior findings. Our findings demonstrate a role for identity-priming by the relevant task in determining attentional capture by faces under high perceptual load. Our results also highlight the importance of considering even relatively subtle forms of task-relevance in selective attention research.

Top-down and bottom-up attentional biases for smoking-related stimuli: Comparing dependent and non-dependent smokers

INTRODUCTION

Substance use causes attentional biases for substance-related stimuli. Both bottom-up (preferential processing) and top-down (inhibitory control) processes are involved in attentional biases. We explored these aspects of attentional bias by using dependent and non-dependent cigarette smokers in order to see whether these two groups would differ in terms of general inhibitory control, bottom-up attentional bias, and top-down attentional biases. This enables us to see whether consumption behaviour would affect these cognitive responses to smoking-related stimuli.

METHODS

Smokers were categorised as either dependent (N = 26) or non-dependent (N = 34) smokers. A further group of non-smokers (N = 32) were recruited to act as controls. Participants then completed a behavioural inhibition task with general stimuli, a smoking-related eye tracking version of the dot-probe task, and an eye-tracking inhibition task with smoking-related stimuli.

RESULTS

Results indicated that dependent smokers had decreased inhibition and increased attentional bias for smoking-related stimuli (and not control stimuli). By contrast, a decreased inhibition for smoking-related stimuli (in comparison to control stimuli) was not observed for non-dependent smokers.

CONCLUSIONS

Preferential processing of substance-related stimuli may indicate usage of a substance, whereas poor inhibitory control for substance-related stimuli may only emerge if dependence develops. The results suggest that how people engage with substance abuse is important for top-down attentional biases.

Examining the effect of perceived performance-contingent gains, losses and errors on arithmetic

Gains and losses have previously been found to differentially modulate Executive Functions and cognitive performance depending on performance contingency. Following recent findings suggesting that random gains and losses modulate arithmetic performance, the current study aimed to investigate the effect of perceived performance-contingent gains and losses on arithmetic performance. In the current study, an arithmetic equation judgment task was administered, with perceived performance-contingent gain, loss, and error feedback presented upon each trial. The results from two experiments suggest that when perceiving gain and loss as performance-contingent, the modulation of arithmetic performance, seen previously under random contingency conditions was entirely eliminated. In addition, another type of feedback was examined in the context of an arithmetic task: post-error adjustments. When performance after error feedback was compared to performance after other aversive performance feedback such as loss signals, only errors, but not other aversive feedback, modulated performance in the subsequent trial. These findings further extend the knowledge regarding the influence of gain and loss situations, as well as errors, on arithmetic performance.

Intact Goal-Driven Attentional Capture in Autistic Adults

BACKGROUND

Autistic individuals have been found to show increased distractibility by salient irrelevant information, yet reduced distractibility by information of personal motivational salience. Here we tested whether these prior discrepancies reflect differences in the automatic guidance of attention by top-down goals.

METHODS

Autistic (self-reported diagnoses, confirmed with scores on the Social Responsiveness Scale) and non-autistic adults, without intellectual disability (IQ > 80 on Wechsler Abbreviated Scale of Intelligence), searched for a color-defined target object (e.g., red) among irrelevant color objects. Spatially uninformative cues, matching either the target color or a nontarget/irrelevant color, were presented prior to each display.

RESULTS

Replicating previous work, only target color cues reliably captured attention, delaying responses when invalidly versus validly predicting target location. Crucially, this capture was robust for both autistic and neurotypical participants, as confirmed by Bayesian analysis. Limitations: While well powered for our research questions, our sample size precluded investigation of the automatic guidance of attention in a diverse group of autistic people (e.g. those with a range of cognitive abilities).

CONCLUSIONS

Our findings imply that key mechanisms underlying the automatic implementation of top-down attentional goals are intact in autism, challenging theories of reduced top-down control.

Attentional Bias in Alcohol and Cannabis Use Disorder Outpatients as Indexed by an Odd-One-Out Visual Search Task: Evidence for Speeded Detection of Substance Cues but Not for Heightened Distraction

Current cognitive models of addiction imply that speeded detection and increased distraction from substance cues might both independently contribute to the persistence of addictive behavior. Speeded detection might lower the threshold for experiencing craving, whereas increased distraction might further increase the probability of entering a bias-craving-bias cycle, thereby lowering the threshold for repeated substance use. This study was designed to examine whether indeed both attentional processes are involved in substance use disorders. Both attentional processes were indexed by an Odd-One-Out visual search task in individuals diagnosed with alcohol use disorder (AUD; n = 63) and cannabis use disorder (CUD; n = 28). To test whether the detection and/or the distraction component are characteristic for AUD and CUD, their indices were compared with matched individuals without these diagnoses (respectively, n = 63 and n = 28). Individuals with CUD showed speeded detection of cannabis cues; the difference in detection between AUD and the comparison group remained inconclusive. Neither the AUD nor the CUD group showed more distraction than the comparison groups. The sample size of the CUD group was relatively small. In addition, participants made relatively many errors in the attentional bias (AB) task, which might have lowered its sensitivity to detect ABs. The current study provided no support for the proposed role of increased distraction in CUD and AUD. The findings did, however, provide support for the view that speeded detection might be involved in CUD. Although a similar trend was evident for AUD, the evidence was weak and remained therefore inconclusive.

Emotional distraction in working memory: Bayesian-based evidence of the equivalent effect of positive and neutral interference

Evidence has shown that negative distracting stimuli are most difficult to control when we are focused in a relevant task, while positive and neutral distractors might be equally overcome. Still, recent meta-analytic evidence has pointed out that differences in the ability to cope with positive or neutral distractors may be difficult to detect in healthy people and in laboratory sets. Here we re-analyse memory performance in four already published working memory experiments in which affective and non-affective distractors were used. We focused on the positive versus neutral contrast, which did not reveal differences in the original analysis, with the aim of quantifying evidence for the null hypothesis using a Bayesian approach. Bayes factor (BF) estimates show substantial evidence in favour to the absence of differences in three out of four datasets. Further, BF aggregated from the four studies shows stronger evidence for the null hypothesis. Results from this analysis show that WM performance after positive and neutral interference can be considered equivalent, suggesting that positive distractors can be overcome to the same extent as neutral ones.

Where's the wine? Heavy social drinkers show attentional bias towards alcohol in a visual conjunction search task

BACKGROUND AND AIMS

Research indicates that high consumers of alcohol exhibit attentional bias (AB) towards alcohol-related cues, suggestive of a cognitive mechanism that might drive substance seeking. Many tasks that measure AB (e.g. visual probe, addiction Stroop), however, are limited by their reliance on non-appetitive control cues, the serial presentation of stimuli and their poor internal reliability. The current study employed a visual conjunction search (VCS) task capable of presenting multiple alcoholic and non-alcoholic appetitive cues simultaneously to assess whether social drinkers attend selectively to alcoholic stimuli. To assess the construct validity of this task, we examined whether alcohol consumption and related problems, subjective craving and drinking motives predict alcohol-specific AB.

DESIGN AND SETTING

A VCS task was performed in a laboratory setting, which required participants to detect the presence of appetitive alcoholic (wine, beer) and non-alcoholic (cola, lemonade) targets within arrays of matching and non-matching distractors.

PARTICIPANTS

Data from 99 participants were assessed [mean_age  = 20.77, standard deviation (SD) = 2.98; 64 (65%) females], with 81.8% meeting the threshold for harmful alcohol consumption (mean_AUDIT  = 12.89, SD = 5.79).

MEASUREMENTS

Self-reports of alcohol consumption and related problems [Alcohol Use Disorders Identification Test (AUDIT)], subjective craving (Alcohol Craving Questionnaire Short Form) and drinking motives (Drinking Motives Questionnaire Short Form) were obtained, and the VCS task measured response times for the correct detection of alcoholic and non-alcoholic targets.

FINDINGS

Participants were significantly quicker to detect alcoholic relative to non-alcoholic appetitive targets (P < 0.001, d_z  = 0.41), which was predicted positively by AUDIT scores (P = 0.013, R²  = 0.06%). The VCS task achieved excellent reliability (α > 0.79), superior to other paradigms.

CONCLUSIONS

The visual conjunction search task appears to be a highly reliable method for assessing alcohol-related attentional bias, and shows that heavy social drinkers prioritize alcoholic cues in their immediate environment.

Conflicting rewards: effects of task goals on attention for alcohol cues

Research has shown that temporary task goals capture more attention than negative, threatening cues, even in anxious individuals. In the current study, we investigated whether temporary task goals would also capture more attention than alcohol-related cues. In Experiment 1, 59 hazardous drinkers performed both a modified dot-probe and a flanker task in which temporary goal- and alcohol-relevant stimuli were presented together. Results of the dot-probe task confirmed an attentional bias towards goal-relevant stimuli in the presence of alcohol cues. This effect was absent in a modified flanker task, although there was a general slowing when the targets appeared on top of goal-relevant stimuli, suggesting that goal-related backgrounds captured more attention than alcohol backgrounds. In Experiment 2, we replicated the dot-probe procedure in 29 hazardous drinkers who had been exposed to a prime dose of alcohol prior to performing the task. Our findings indicate that temporary goal stimuli are more salient than alcohol cues, which might lead the way to novel clinical applications.

Knowledge about the predictive value of reward conditioned stimuli modulates their interference with cognitive processes

Stimuli conditioned with a substance can generate drug-approach behaviors due to their acquired motivational properties. According to implicit theories of addiction, these stimuli can decrease cognitive control automatically. The present study (n = 49) examined whether reward-associated stimuli can interfere with cognitive processes in the absence of knowledge about stimulus–outcome contingencies. Conditioned stimuli (CS) were paired with high-reward (HR) or low-reward (LR) probabilities of monetary reward using a Pavlovian learning task. Participants were categorized as Aware or Unaware of contingencies using a Bayesian analysis. CS were then used as task-irrelevant distractors in modified flanker and N-back tasks. Results show HR CS can generate increased interference in the flanker task for participants Unaware of contingencies, contributing further evidence for the existence of implicit Pavlovian conditioning. For the N-back task, working memory performance was affected by HR CS, albeit only for Aware participants. These results suggest that CS can interfere implicitly with cognitive processes in a similar way to drug-related stimuli. Such an effect could occur in a stimulus-driven fashion, devoid of top-down goal-directedness. These findings have implications for the conceptualization and study of implicit processes in addiction and highlights the necessity to reconsider the measurement of such phenomena.

Prehabilitation in Alcohol Dependence as a Treatment Model for Sustainable Outcomes. A Narrative Review of Literature on the Risks Associated With Detoxification, From Animal Models to Human Translational Research

In this review paper, we discuss how the overarching concept of prehabilitation is applicable to alcohol dependence. Central to prehabilitation are the concepts of expected harm, risks, and proactive planning to eliminate the harm or cope with the risks. We review the evidence from animal models, psychological experimental studies, as well as pharmacological studies, on the potential risks and harms associated with medically assisted alcohol detoxification and the current treatment paradigm for alcohol dependence. Animal models provide an approximation mostly of the physical aspect of alcohol withdrawal and detoxification process and make predictions about the development of the phenomena in humans. Despite their limitations, these models provide good evidence that withdrawal from chronic ethanol use induces cognitive impairment, which is worsened by repeated bouts of withdrawal and that these impairments are dependent on the duration of alcohol withdrawal. Initial clinical observations with alcohol-dependent patients confirmed increased incidence of seizures. In recent years, accumulating evidence suggests that patients who have had repeated episodes of withdrawal also show changes in their affect, increased craving, as well as significant deterioration of cognitive abilities, when compared to patients with fewer withdrawals. Alcohol dependence is associated with tolerance and withdrawal, with neuroadaptations in γ-Aminobutyric Acid-A Receptor (GABA-A) and glutamatergic N-methyl-D-aspartate (NMDA) receptors playing key roles. It is suggested that dysregulation of the NMDA receptor system underpins alcohol-related memory impairments. Finally, we discuss the Structured Preparation for Alcohol Detoxification (SPADe) as an example of how prehabilitation has been applied in clinical practice. We discuss the importance of partial control over drinking as an interim step toward abstinence and early introduction of lifestyle changes for both the patient and the immediate environment prior to detoxification and while the patient is still drinking.

Beer? Over here! Examining attentional bias towards alcoholic and appetitive stimuli in a visual search eye-tracking task

RATIONALE

Experimental tasks that demonstrate alcohol-related attentional bias typically expose participants to single-stimulus targets (e.g. addiction Stroop, visual probe, anti-saccade task), which may not correspond fully with real-world contexts where alcoholic and non-alcoholic cues simultaneously compete for attention. Moreover, alcoholic stimuli are rarely matched to other appetitive non-alcoholic stimuli.

OBJECTIVES

To address these limitations by utilising a conjunction search eye-tracking task and matched stimuli to examine alcohol-related attentional bias.

METHODS

Thirty social drinkers (Mage = 19.87, SD = 1.74) were asked to detect whether alcoholic (beer), non-alcoholic (water) or non-appetitive (detergent) targets were present or absent amongst a visual array of matching and non-matching distractors. Both behavioural response times and eye-movement dwell time were measured.

RESULTS

Social drinkers were significantly quicker to detect alcoholic and non-alcoholic appetitive targets relative to non-appetitive targets in an array of matching and mismatching distractors. Similarly, proportional dwell time was lower for both alcoholic and non-alcoholic appetitive distractors relative to non-appetitive distractors, suggesting that appetitive targets were relatively easier to detect.

CONCLUSIONS

Social drinkers may exhibit generalised attentional bias towards alcoholic and non-alcoholic appetitive cues. This adds to emergent research suggesting that the mechanisms driving these individual's attention towards alcoholic cues might 'spill over' to other appetitive cues, possibly due to associative learning.