Retraining automatic action tendencies in obesity

Virtual reality assessment of a high-calorie food bias: Replication and food-specificity in healthy participants

BACKGROUND

Theoretical models and behavioural studies indicate faster approach behaviour for high-calorie food (approach bias) among healthy participants. A previous study with Virtual Reality (VR) and online motion-capture quantified this approach bias towards food and non-food cues in a controlled VR environment with hand movements. The aim of this study was to test the specificity of a manual approach bias for high-calorie food in grasp movements compared to low-calorie food and neutral objects of different complexity, namely, simple balls and geometrically more complex office tools.

METHODS

In a VR setting, healthy participants (N = 27) repeatedly grasped or pushed high-calorie food, low-calorie food, balls and office tools in randomized order with 30 item repetitions. All objects were rated for valence and arousal.

RESULTS

High-calorie food was less attractive and more arousing in subjective ratings than low-calorie food and neutral objects. Movement onset was faster for high-calorie food in push-trials, but overall push responses were comparable. In contrast, responses to high-calorie food relative to low-calorie food and to control objects were faster in grasp trials for later stages of interaction (grasp and collect). Non-parametric tests confirmed an approach bias for high-calorie food.

CONCLUSION

A behavioural bias for food was specific to high-calorie food objects. The results confirm the presence of bottom-up advantages in motor-cognitive behaviour for high-calorie food in a non-clinical population. More systematic variations of object fidelity and in clinical populations are outstanding. The utility of VR in assessing approach behaviour is confirmed in this study by exploring manual interactions in a controlled environment.

Neural correlates of changing food choices while bypassing values

Current theories suggest that altering choices requires value modification. To investigate this, normal-weight female participants' food choices and values were tested before and after an approach-avoidance training (AAT), while neural activity was recorded during the choice task using functional magnetic resonance imaging (fMRI). During AAT, participants consistently approached low- while avoiding high-calorie food cues. AAT facilitated low-calorie food choices, leaving food values unchanged. Instead, we observed a shift in indifference points, indicating the decreased contribution of food values in food choices. Training-induced choice shifts were associated with increased activity in the posterior cingulate cortex (PCC). In contrast, the medial PFC activity was not changed. Additionally, PCC grey matter density predicted individual differences in training-induced functional changes, suggesting anatomic predispositions to training impact. Our findings demonstrate neural mechanisms underlying choice modulation independent of valuation-related processes, with substantial theoretical significance for decision-making frameworks and translational implications for health-related decisions resilient to value shifts.

The Role of Habit Formation and Automaticity in Diabetes Self-Management: Current Evidence and Future Applications

PURPOSE OF REVIEW

Diabetes is a chronic condition that requires consistent self-management for optimal health outcomes. People with diabetes are prone to burnout, cognitive burden, and sub-optimal performance of self-management tasks. Interventions that focus on habit formation have the potential to increase engagement by facilitating automaticity of self-management task performance. The purpose of this review is to (1) clarify the conceptualizations of habit formation and behavioral automaticity in the context of health behavior interventions, (2) review the evidence of habit in relation to behaviors relevant to diabetes self-management, and (3) discuss opportunities for incorporating habit formation and automaticity into diabetes self-management interventions.

RECENT FINDINGS

Modern habit research describes a habit as a behavior that results over time from an automatic mental process. Automatic behaviors are experienced as cue-dependent, goal-independent, unconscious, and efficient. Habit formation requires context-dependent repetition to form cue-behavior associations. Results of diabetes habit studies are mixed. Observational studies have shown positive associations between habit strength and target self-management behaviors such as taking medication and monitoring blood glucose, as well as glycemic outcomes such as HbA1c. However, intervention studies conducted in similar populations have not demonstrated a significant benefit of habit-forming interventions compared to controls, possibly due to varying techniques used to promote habit formation. Automaticity of self-management behaviors has the potential to minimize the burden associated with performance of self-management tasks and ultimately improve outcomes for people with diabetes. Future studies should focus on refining interventions focused on context-dependent repetition to promote habit formation and better measurement of habit automaticity in diabetes self-management.

A Program for the Comprehensive Cognitive Training of Excess Weight (TRAINEP): The Study Protocol for A Randomized, Controlled Trial

Background: The available treatments for people with excess weight have shown small effects. Cognitive training has shown promising results, but most of the research focused on normal-weight university students and reported immediate results after a single training session. This parallel group, randomized, controlled trial aims to study the efficacy of a program for the comprehensive cognitive treatment of excess weight. Methods and Analysis: Participants will be 150 people with excess weight recruited through social media, who will be randomized into three groups: cognitive intervention, sham cognitive intervention, and treatment as usual. All assessment and intervention sessions will be online in groups of 5–6 participants. The three groups will attend a motivational interviewing session, and they will receive individualized diet and physical exercise guidelines throughout the program. The cognitive training will consist of four weekly sessions of approximately 60–90 min, each based on approach–avoidance bias training, inhibitory control training, implementation of intentions, and episodic future thinking, respectively. The main outcome measure will be a change in Body Mass Index (kg/m2). Secondary outcomes include changes in cognitive measures, eating and physical exercise behaviors, and anthropometric measures. Assessments will be conducted up to 6 months after the end of the program. In addition, data on the use of the health system will be collected to analyze the cost-effectiveness and the cost-utility of training. Linear mixed models will be used for statistical analysis. Findings of this study will expand the available evidence on cognitive interventions to reduce excess weight.

EXPRESS: Reliability and Convergence of Approach/Avoidance Bias Assessment Tasks in the Food Consumption Domain

Theories of motivation posit that people will more readily approach positive or appetitive stimuli, and there has been growing interest in the relationship between biases in approach and avoidance behaviours for food cues and food craving and consumption behaviour. Two paradigms commonly employed by research to investigate this relationship are the Approach Avoidance Task (AAT) and the Stimulus Response Compatibility Task (SRCT). However, it is yet to be determined whether the measures yielded by these tasks reflect the same processes operating in the food craving and consumption domain. The present study examined the internal reliability and convergence of AAT and SRCT paradigms in their assessment of biased approach to unhealthy compared to healthy food stimuli, and whether the measures yielded by the AAT and SRCT paradigms demonstrated associations with individual differences in food craving and eating behaviour. One hundred and twenty-one participants completed an SRCT, an AAT using an arm movement response mode, and an AAT using a key-press response mode. The measures yielded comparable and acceptable levels of internal consistency, but convergence between the different task bias scores was modest or absent, and only approach bias as measured with the AAT task using an arm movement response mode was associated with self-report measures of eating behaviour and trait food craving. Thus, tasks did not converge strongly enough to be considered equivalent measures of approach/avoidance biases, and the AAT task using an arm movement response seems uniquely suited to detecting approach biases argued to characterise maladaptive eating behaviour and craving.

Parsing the link between reinforcement sensitivity theory and eating behavior: A systematic review

The Reinforcement Sensitivity Theory (RST) is a widely studied psychobiological model of personality. RST factors seem to influence eating behavior, but how these personality traits are associated with distinct features of eating behavior is still unclear. In the present systematic review, we analyzed the relationship between RST personality factors and eating behavior using a parsing approach in which BMI-related results, self-reported results, and behavioral results were distinguished. Our analysis revealed that reward and punishment sensitivity seem to correlate and influence distinct features of eating behavior. The association between BMI and RST factors was uncertain, but nonlinear associations between reward sensitivity and weight need further testing. Reward sensitivity was linked to most eating behavior phenotypes (e.g., emotional eating and restrained eating), but only punishment sensitivity was primarily correlated with eating pathology. Reward sensitivity was the main factor linked with reactivity to food stimuli on many behavioral measures. The neurobiological personality factors of RST offer parsimonious concepts to understand eating behavior outcomes and the differential relationships observed are useful to translational research.

The evidential value of research on cognitive training to change food-related biases and unhealthy eating behavior: A systematic review and p-curve analysis

Cognitive bias modification (CBM), which retrains implicit biases towards unhealthy foods, has been proposed as a promising adjunct to improve the efficacy of weight loss interventions. We conducted a systematic review of research on three CBM approaches (i.e., cue-specific inhibitory control, approach bias modification, and attentional bias modification) for reducing unhealthy eating biases and behavior. We performed a p-curve analysis to determine the evidential value of this research; this method is optimally suited to clarify whether published results reflect true effects or false positives due to publication and reporting biases. When considering all CBM approaches, our results suggested that the findings of CBM trials targeting unhealthy eating are unlikely to be false positives. However, only research on attentional bias modification reached acceptable levels of power. These results suggest that CBM interventions may be an effective strategy to enhance the efficacy of weight loss interventions. However, there is room for improvement in the methodological standards of this area of research, especially increasing the statistical power can help to fully clarify the clinical potential of CBM, and determine the role of potential moderators.

Healthiness matters: Approach motivation for healthy food in overweight and obese individuals

It is well documented that approach tendencies for appetitive substances play a role in certain unhealthy patterns of consumption. However, it remains uncertain whether overweight individuals differ from healthy-weight individuals in terms of their tendency to approach unhealthy foods. Thus, the present study aimed to empirically test the hypothesis that overweight individuals are characterised by an elevated behavioural tendency to approach unhealthy food, rather than healthy food, as compared to healthy-weight individuals. Participants were forty-one overweight individuals (Mean BMI = 30.40 kg/m²) and forty-five healthy-weight individuals (Mean BMI = 22.17 kg/m²) aged between 17 and 47. They completed an Approach-Avoidance Task to assess behavioural approach-avoidance tendencies towards healthy and unhealthy food. Contrary to the hypothesis under test, results revealed a greater approach tendency towards healthy food in overweight individuals, as compared to healthy-weight individuals, whereas there were no group differences in behavioural approach-avoidance tendencies towards unhealthy food. These novel findings suggest that overweight individuals are characterised by an approach motivation for healthy food. We provide suggestions concerning how future researchers can build on these findings to test whether this approach tendency contributes to consumption behaviour in overweight individuals.

A dismantling study on imaginal retraining in overweight or obese women

Imaginal retraining is a variant of approach bias modification and transfers the method into one's own mind. As the technique contains multiple elements, this pilot study aimed to dismantle which of its components is most efficient in reducing craving for high-calorie food. A total of 113 women were randomly allocated to one out of six conditions containing a short intervention to mentally manipulate a picture displaying high-calorie foods. Four of the interventions involved different combinations of elements of the imaginal retraining technique, while the remaining two conditions comprised thought suppression or merely observing a picture. Participants rated their level of craving, as well as three pictures containing healthy and unhealthy foods regarding their pleasantness before and after the interventions took place. Within-group changes were assessed with paired t-tests (in case of non-normal data Wilcoxon paired t-tests) and between-group differences with one-way ANOVAs (non-parametric Kruskal-Wallis tests). A trend level reduction in craving was found in the imaginal retraining condition with and without a movement. A post hoc analysis of both conditions joint together showed a statistically significant reduction in craving. In addition, positive picture appraisal for unhealthy foods was significantly reduced in both imaginal retraining conditions (with and without movement) with medium to large effect sizes. This study demonstrated that imaginal retraining with an arm movement can reduce craving and picture appraisal for high-calorie foods significantly in a one-time application. It is a promising technique to reduce appraisal for unhealthy high-calorie foods. Future studies should repeat the experiment in situations of high craving and allow for a personalized selection of stimuli.

Signs of Warning: Do Health Warning Messages on Sweets Affect the Neural Prefrontal Cortex Activity?

In the global attempt to combat rising obesity rates, the introduction of health warning messages on food products is discussed as one possible approach. However, the perception of graphical health warning messages in the food context and the possible impact that they may have, in particular at the neuronal level, have hardly been studied. Therefore, the aim of this explorative study was to examine consumers’ reactions (measured as neuronal activity and subjective reporting) of two different types of graphical health warning messages on sweets compared to sweets without warning messages. One type used the red road traffic stop sign as graphical information (“Stop”), while the other one used shocking pictures (“Shock”), an approach similar to the images on cigarette packages. The neural response of 78 participants was examined with the neuroimaging technique functional near-infrared spectroscopy (fNIRS). Different hemodynamic responses in the orbitofrontal cortex (OFC), the frontopolar cortex (FOC), and the dorsolateral prefrontal cortex (dlPFC) were observed, regions which are associated with reward evaluation, social behavior consequences, and self-control. Further, the health warning messages were actively and emotionally remembered by the participants. These findings point to an interesting health information strategy, which should be explored and discussed further.

Is obesity related to enhanced neural reactivity to visual food cues? A review and meta-analysis

Theoretical work suggests that obesity is related to enhanced incentive salience of food cues. However, evidence from both behavioral and neuroimaging studies on the topic is mixed. In this work we review the literature on cue reactivity in obesity and perform a preregistered meta-analysis of studies investigating effects of obesity on brain responses to passive food pictures viewing. Further, we examine whether age influences brain responses to food cues in obesity. In the meta-analysis we included 13 studies of children and adults that investigated group differences (obese vs. lean) in responses to food vs. non-food pictures viewing. While we found no significant differences in the overall meta-analysis, we show that age significantly influences brain response differences to food cues in the left insula and the left fusiform gyrus. In the left insula, obese vs. lean brain differences in response to food cues decreased with age, while in the left fusiform gyrus the pattern was opposite. Our results suggest that there is little evidence for obesity-related differences in responses to food cues and that such differences might be mediated by additional factors that are often not considered.

How interindividual differences shape approach-avoidance behavior: Relating self-report and diagnostic measures of interindividual differences to behavioral measurements of approach and avoidance

Responding to stimuli in ambiguous environments is partially governed by approach-avoidance tendencies. Imbalances in these approach-avoidance behaviors are implicated in many mental disorders including anxiety disorders, phobias and substance use disorders. While factors biasing human behavior in approach-avoidance conflicts have been researched in numerous experiments, a much-needed comprehensive overview integrating those findings is missing. Here, we systematically searched the existing literature on individual differences in task-based approach-avoidance behavior and aggregated the current evidence for the effect of self-reported approach/avoidance traits, anxiety and anxiety disorders, specific phobias, depression, aggression, anger and psychopathy, substance use and related disorders, eating disorders and habits, trauma, acute stress and, finally, hormone levels (mainly testosterone, oxytocin). We highlight consistent findings, underrepresented research areas and unexpected results, and detail the amount of controversy between studies. We discuss potential reasons for ambiguous results in some research areas, offer practical advice for future studies and highlight potential variables such as task-related researcher decisions that may influence how interindividual differences and disorders drive automatic approach-avoidance biases in behavioral experiments.

Reduced automatic approach tendencies towards task-relevant and task-irrelevant food pictures in Anorexia Nervosa

BACKGROUND AND OBJECTIVES

Anorexia Nervosa (AN) patients are characterized by an excessive restriction of their food-intake. Prior research using an Affective Simon Task (AST) with food as a task-irrelevant feature, provided evidence for the view that AN patients' ability to refrain from food is facilitated by reduced automatic approach tendencies towards food. However, because food was task-irrelevant (i.e., participants had to base their reaction on the perspective of the picture and not on its content), the findings may in fact reflect a relatively strong ability to ignore the content of the food stimuli rather than weakened approach towards food per se. Therefore, this study also included a Stimulus Response Compatibility (SRC) task with food as task-relevant feature that could not be ignored, because the required response depended on the [food vs non-food] content of the pictures.

METHODS

AN spectrum patients (n = 63), and a comparison group of adolescents without eating pathology (n = 57) completed both a SRC task with food as task-relevant feature, and an Affective Simon Task AST with food as task-irrelevant feature.

RESULTS

AN patients showed reduced approach tendencies for high caloric food. Only the SRC uniquely predicted the presence of AN.

LIMITATIONS

Comparison between tasks was hampered because the SRC only included high caloric food stimuli, whereas the AST included high and low caloric food stimuli.

CONCLUSION

Patients with AN are characterized by weakened automatic approach of high caloric food. This might 'help' restrict their food-intake even in a condition of starvation.

Imaginal retraining decreases craving for high-calorie food in overweight and obese women: A randomized controlled trial

Overweight and obesity are epidemic conditions. Obesity is associated with somatic and psychological sequelae, including serious life-shortening disorders (e.g., diabetes). This study aimed to evaluate the efficacy of a newly developed imaginal variant of approach bias modification (i.e., imaginal retraining) for the reduction of craving for high-calorie food. In a randomized controlled trial, 384 women with a body mass index above 25 were allocated to a wait-list control group or to two variants of imaginal retraining (ratio: 1; 0.5; 0.5). The two intervention groups were sent a manual on imaginal retraining. One group was explicitly encouraged and instructed to use electronic reminders (RER); the standard retraining group (RS) was not encouraged to use electronic reminders. Assessments were 6 weeks apart and were carried out online. Craving for high-calorie food represented the primary outcome (based on the Visual Analog Scale, VAS). Secondary outcomes included the Food Cravings Questionnaire (FCQ-T-R). The study was registered as DRKS00017220. Women in the RER group utilized the retraining technique more often than those in the RS condition, and utilization frequency in turn was associated with improvement on craving and eating behavior scales. Both intention-to-treat and per-protocol analyses showed a favorable effect of the RER group, which achieved significance on the primary outcome, as well as on several other outcomes relative to controls at a small to medium effect size. For those participants who measured their weight before and after the assessment using a scale, weight loss in the RER group was significantly greater compared to the control group. Both retraining groups (RER: 39.4%; RS: 31.1%) reduced their subjective amount of eating relative to controls (24.2%). Approximately two-thirds of the sample (68.3%) performed the exercises at least once during the study period. The present results show that, when used regularly, imaginal retraining may reduce craving for high-calorie food in overweight and obese women. Of note, there was also evidence suggestive of weight reduction, although no diet or lifestyle change was recommended in the manual. Because a large subgroup neither read the manual nor performed the exercises, we recommend that future imaginal retraining be conveyed via short video clips.

Hemispheric asymmetries in resting-state EEG and fMRI are related to approach and avoidance behaviour, but not to eating behaviour or BMI

Much of our behaviour is driven by two motivational dimensions—approach and avoidance. These have been related to frontal hemispheric asymmetries in clinical and resting‐state EEG studies: Approach was linked to higher activity of the left relative to the right hemisphere, while avoidance was related to the opposite pattern. Increased approach behaviour, specifically towards unhealthy foods, is also observed in obesity and has been linked to asymmetry in the framework of the right‐brain hypothesis of obesity. Here, we aimed to replicate previous EEG findings of hemispheric asymmetries for self‐reported approach/avoidance behaviour and to relate them to eating behaviour. Further, we assessed whether resting fMRI hemispheric asymmetries can be detected and whether they are related to approach/avoidance, eating behaviour and BMI. We analysed three samples: Sample 1 (n = 117) containing EEG and fMRI data from lean participants, and Samples 2 (n = 89) and 3 (n = 152) containing fMRI data from lean, overweight and obese participants. In Sample 1, approach behaviour in women was related to EEG, but not to fMRI hemispheric asymmetries. In Sample 2, approach/avoidance behaviours were related to fMRI hemispheric asymmetries. Finally, hemispheric asymmetries were not related to either BMI or eating behaviour in any of the samples. Our study partly replicates previous EEG findings regarding hemispheric asymmetries and indicates that this relationship could also be captured using fMRI. Our findings suggest that eating behaviour and obesity are likely to be mediated by mechanisms not directly relating to frontal asymmetries in neuronal activation quantified with EEG and fMRI.

Effects of a Smartphone-Based Approach-Avoidance Intervention on Chocolate Craving and Consumption: Randomized Controlled Trial

BACKGROUND

Repeatedly pushing high-calorie food stimuli away based on joystick movements has been found to reduce approach biases toward these stimuli. Some studies also found that such avoidance training reduced consumption of high-calorie foods.

OBJECTIVE

This study aimed to test effects of a smartphone-based approach-avoidance intervention on chocolate craving and consumption, to make such interventions suitable for daily use.

METHODS

Within a 10-day period, regular chocolate eaters (n=105, 86% female) performed five sessions during which they continuously avoided (ie, swiped upward) chocolate stimuli (experimental group, n=35), performed five sessions during which they approached and avoided chocolate stimuli equally often (placebo control group, n=35), or did not perform any training sessions (inactive control group, n=35). Training effects were measured during laboratory sessions before and after the intervention period and further continuously through daily ecological momentary assessment.

RESULTS

Self-reported chocolate craving and consumption as well as body fat mass significantly decreased from pre- to postmeasurement across all groups. Ecological momentary assessment reports evidenced no differences in chocolate craving and consumption between intervention days and rest days as a function of the group.

CONCLUSIONS

A smartphone-based approach-avoidance training did not affect eating-related and anthropometric measures over and above measurement-based changes in this study. Future controlled studies need to examine whether other techniques of modifying food approach tendencies show an add-on benefit over conventional, monitoring-based intervention effects.

TRIAL REGISTRATION

AsPredicted 8203; https://aspredicted.org/pt9df.pdf.

Combining cognitive bias modification training (CBM) and transcranial direct current stimulation (tDCS) to treat binge eating disorder: study protocol of a randomised controlled feasibility trial

INTRODUCTION

Binge eating disorder (BED) is a common mental disorder, closely associated with obesity. Existing treatments are only moderately effective with high relapse rates, necessitating novel interventions. This paper describes the rationale for, and protocol of, a feasibility randomised controlled trial (RCT), evaluating the combination of transcranial direct current stimulation (tDCS) and a computerised cognitive training, namely approach bias modification training (ABM), in patients with BED who are overweight or obese. The aim of this trial is to obtain information that will guide decision-making and protocol development in relation to a future large-scale RCT of combined tDCS+ABM treatment in this group of patients, and also to assess the preliminary efficacy of this intervention.

METHODS AND ANALYSIS

66 participants with Diagnostic and Statistical Manual-5 diagnosis of BED and a body mass index (BMI) of ≥25 kg/m2 will be randomly allocated to one of three groups: ABM+real tDCS; ABM+sham tDCS or a wait-list control group. Participants in both intervention groups will receive six sessions of ABM+real/sham tDCS over 3 weeks; engaging in the ABM task while simultaneously receiving bilateral tDCS to the dorsolateral prefrontal cortex. ABM is based on an implicit learning paradigm in which participants are trained to enact an avoidance behaviour in response to visual food cues. Assessments will be conducted at baseline, post-treatment (3 weeks) and follow-up (7 weeks post-randomisation). Feasibility outcomes assess recruitment and retention rates, acceptability of random allocation, blinding success (allocation concealment), completion of treatment sessions and research assessments. Other outcomes include eating disorder psychopathology and related neurocognitive outcomes (ie, delay of gratification and inhibitory control), BMI, other psychopathology (ie, mood), approach bias towards food and surrogate endpoints (ie, food cue reactivity, trait food craving and food intake).

ETHICS AND DISSEMINATION

This study has been approved by the North West-Liverpool East Research Ethics Committee. Results will be published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ISRCTN35717198.

Food Addiction: Implications for the Diagnosis and Treatment of Overeating

With the obesity epidemic being largely attributed to overeating, much research has been aimed at understanding the psychological causes of overeating and using this knowledge to develop targeted interventions. Here, we review this literature under a model of food addiction and present evidence according to the fifth edition of the Diagnostic and Statistical Manual (DSM-5) criteria for substance use disorders. We review several innovative treatments related to a food addiction model ranging from cognitive intervention tasks to neuromodulation techniques. We conclude that there is evidence to suggest that, for some individuals, food can induce addictive-type behaviours similar to those seen with other addictive substances. However, with several DSM-5 criteria having limited application to overeating, the term 'food addiction' is likely to apply only in a minority of cases. Nevertheless, research investigating the underlying psychological causes of overeating within the context of food addiction has led to some novel and potentially effective interventions. Understanding the similarities and differences between the addictive characteristics of food and illicit substances should prove fruitful in further developing these interventions.

Imaginal retraining reduces alcohol craving in problem drinkers: A randomized controlled trial

BACKGROUND AND OBJECTIVES

Retraining, a psychological intervention derived from the approach-avoidance paradigm, has yielded mixed results for the treatment of alcohol use disorder as well as other forms of addiction. The present study investigated the efficacy of an imaginal variant of retraining that allowed greater personalization of the content.

METHODS

Within the framework of a randomized controlled trial (RCT), 84 individuals with self-reported alcohol-related problems were recruited over the Internet and allocated to either imaginal retraining (treatment manual dispatched as a pdf-file via email) or a wait-list control group (with care-as-usual). The intervention period was four weeks. Alcohol craving, as measured with a visual analogue scale (VAS), served as the primary outcome. Other emotional (e.g. self-esteem) and drinking-related variables served as secondary outcomes.

RESULTS

Both per-protocol (PP) and intention-to-treat (ITT) analyses showed that imaginal retraining led to a significant reduction in alcohol craving compared to the control group at a large effect size. Self-esteem improved in the retraining condition relative to controls in the PP and one of the ITT analyses; 75% of the individuals in the treatment group reported less alcohol consumption in the treatment period, whereas drinking behavior remained essentially unchanged in the control group (p < .001) (the trial was registered at the German Clinical Trials Register, DRKS00015319).

LIMITATIONS

Whether the effects of imaginal retraining are sustained over time needs to be established. Attrition was significantly higher in the retraining group (40.5%) than in the control group (16.7%). Designs with an active control condition are needed as well as dismantling studies to explore which of the treatment's multiple components best predicts improvement. Future studies should verify participants' alcohol consumption levels using objective measures.

CONCLUSION

Imaginal retraining led to significant effects on the reduction of alcohol craving.

Appetitive Pavlovian-to-Instrumental Transfer in Participants with Normal-Weight and Obesity

Altered eating behavior due to modern, food-enriched environments has a share in the recent obesity upsurge, though the exact mechanisms remain unclear. This study aims to assess whether higher weight or weight gain are related to stronger effects of external cues on motivation-driven behavior. 51 people with and without obesity completed an appetitive Pavlovian-to-Instrumental Transfer (PIT) paradigm. During training, button presses as well as presentation of fractal images resulted in three palatable and one neutral taste outcome. In the subsequent test phase, outcome-specific and general behavioral bias of the positively associated fractal images on deliberate button press were tested under extinction. While all participants showed signs of specific transfer, general transfer was not elicited. Contrary to our expectations, there was no main effect of weight group on PIT magnitude. Participants with obesity exhibited higher scores in the Three-Factor Eating Questionnaire Disinhibition scale, replicating a very robust effect from previous literature. Individual Restraint scores were able to predict body-mass index (BMI) change after a three-year period. Our data indicate that PIT is an important player in how our environment influences the initiation of food intake, but its effects alone cannot explain differences in-or future development of-individual weight.

Unhealthy yet Avoidable-How Cognitive Bias Modification Alters Behavioral and Brain Responses to Food Cues in Individuals with Obesity

Obesity is associated with automatically approaching problematic stimuli, such as unhealthy food. Cognitive bias modification (CBM) could beneficially impact problematic approach behavior. However, it is unclear which mechanisms are targeted by CBM in obesity. Candidate mechanisms include: (1) altering reward value of food stimuli; and (2) strengthening inhibitory abilities. Thirty-three obese adults completed either CBM or sham training during functional magnetic resonance imaging (fMRI) scanning. CBM consisted of implicit training to approach healthy and avoid unhealthy foods. At baseline, approach tendencies towards food were present in all participants. Avoiding vs. approaching food was associated with higher activity in the right angular gyrus (rAG). CBM resulted in a diminished approach bias towards unhealthy food, decreased activation in the rAG, and increased activation in the anterior cingulate cortex. Relatedly, functional connectivity between the rAG and right superior frontal gyrus increased. Analysis of brain connectivity during rest revealed training-related connectivity changes of the inferior frontal gyrus and bilateral middle frontal gyri. Taken together, CBM strengthens avoidance tendencies when faced with unhealthy foods and alters activity in brain regions underpinning behavioral inhibition.