Novel methods to help develop healthier eating habits for eating and weight disorders: A systematic review and meta-analysis

Inhibitory control training to reduce appetitive behaviour: a meta-analytic investigation of effectiveness, potential moderators, and underlying mechanisms of change

BACKGROUND/AIMS

Inhibitory control training (ICT) is a cognitive intervention that has been suggested to reduce problematic appetitive behaviours, such as unhealthy eating and excessive alcohol consumption. We conducted a meta-analytic review of ICT for reducing appetitive behaviours.

METHODS

Two meta-analyses were conducted for behavioural (objective) outcomes and self-report outcomes, along with 14 moderator analyses, and two secondary analyses investigating changes in cue-devaluation and inhibitory control.

RESULTS

The review included 46 articles (67 effect sizes and 4231 participants) and four appetitive health behaviours (eating, drinking, smoking, gambling). A significant effect of ICT on behavioural outcomes was found (SMD = 0.241, p .001). The self-report outcomes meta-analysis was not significant (p > .05). Secondary analyses also demonstrated greater inhibitory control (p < .05) and cue devaluation (p < .05) following ICT.

CONCLUSIONS

This meta-analytic review is the largest synthesis of ICT interventions for appetitive behaviours. ICT significantly reduced problematic eating behaviours when adopting behavioural outcomes, but this was not found for other appetitive behaviours. ICT also significantly improved inhibitory control and reduced cue evaluations. Further studies are required before drawing any conclusions regarding impacts on other appetitive behaviours.

Investigation of Ukrainian refugees' eating behavior, food intake, and psychological distress: Study protocol and baseline data

Since the start of the war in Ukraine, almost 8 million people left the country; more than 1 million of them relocated to Germany. It is to be expected that the war puts considerable strain on refugees, which will impact the public health system in host countries. This paper presents baseline data and protocol of longitudinal online experimental study of 619 Ukrainian refugees in Germany started in autumn 2022, focusing on participants' self-reports of appetite, food intake, and levels of stress, anxiety, and depressive symptoms to examine their associations. Results indicate that levels of stress, anxiety, and depressive symptoms in refugees significantly exceed the indicators of relevant parameters as reported by independent large-scale surveys conducted in Ukraine before the war as well as strong correlations between these deviations (.59 ≤ r ≤ .69, p = .005). Changes in appetite were related to more severe psycho-emotional deviations (.15 ≤ r ≤ .19, p = .003) and somewhat unhealthier food intake (r = -.08, p < .001). The study underlines the need of psychological care for refugees to improve their mental health and counteract potential negative consequences for physical health via changes in food intake, for which suitable interventions need to be developed.

Concurrent self-administered transcranial direct current stimulation and attention bias modification training in binge eating disorder: feasibility randomised sham-controlled trial

BACKGROUND

Binge eating disorder (BED) is a common and disabling condition, typically presenting with multiple psychiatric and obesity-related comorbidities. Evidence-based treatments are either resource-intensive (psychotherapies) or have side-effects (medications): these achieve remission in around 50% of cases. Novel treatments are needed.

AIMS

This randomised sham-controlled trial aimed to assess feasibility, acceptability and preliminary efficacy of at-home, self-administered transcranial direct current stimulation (tDCS) and attention bias modification training (ABMT) in adults with binge eating disorder.

METHOD

Eighty-two participants with binge eating disorder were randomly allocated to real tDCS with ABMT, sham tDCS with ABMT, ABMT only or waitlist control. Intervention groups received ten sessions of their allocated treatment over 2-3 weeks. tDCS (2 mA, 20 min) was self-administered using a bilateral (anode right/cathode left) montage targeting the dorsolateral prefrontal cortex. Outcomes were assessed at baseline, post-treatment and 6-week follow-up.

RESULTS

Prespecified feasibility criteria (recruitment ≥80 participants and retention rate ≥75%) were exceeded, and treatment completion rates were high (98.7%). All interventions reduced binge eating episodes, eating disorder symptoms and related psychopathology between baseline and follow-up, relative to waitlist control (medium-to-large between-group effect sizes for change scores). Small-to-medium effect sizes for change scores favoured real tDCS with ABMT versus comparators, suggesting the verum intervention produces superior outcomes.

CONCLUSIONS

At-home, self-administered tDCS with ABMT is feasible and acceptable, and preliminary data on efficacy are promising. This approach could be a useful and scalable alternative or adjunct to established treatments for binge eating disorder. Confirmatory trials can, and should, be pursued.

Response inhibition training as an intervention to modify liking and wanting for foods based on energy density: a proof of concept study

The ubiquity of energy-dense, processed foods has been implicated as a salient feature of the modern 'obesogenic' environment. Cognitive strategies, such as response inhibition training, have been demonstrated to reduce the hedonic value of such foods in previous studies. However, this effect has generally been inconsistent or heterogenous, depending on the outcome measure, characteristics of the sample, and the specificity of food stimuli. Characterising the extent of generalised effects may help define the application of this type of intervention in natural settings. A repeated-measures, proof-of-concept study, using mobile app-based response inhibition training (RIT) versus a control app-based activity (N = 25), was undertaken to establish the valid application of a food reward measure to assess intervention efficacy. Liking (i.e., affect) and wanting (i.e., motivation) for food stimuli categorised by energy density were taken concurrently pre- and post-training. A statistically significant reduction in explicit liking, but not implicit wanting, for foods irrespective of their energy density was observed during the RIT app-based training session relative to the control (p = .041, ηp2 = .16). However, effect sizes associated with devaluation of energy-dense relative to low calorie food stimuli, although non-significant, were higher when measured as implicitly wanting (p = .098, ηp2 = .11) than explicit liking (p = .756, ηp2 = .00). Trends in explicit stimulus evaluations were empirically discordant from implicit evaluations for low calorie foods in particular. Additional research is needed to investigate whether these trends are reproducible with larger samples, trained and novel food stimuli in outcome measures, and more comprehensive training protocols.

Can smartphone-based response inhibition training elicit sustained changes in appetite, preference, and cravings for energy-dense foods? A free-living randomized controlled trial

BACKGROUND

Food-specific response inhibition training has been implemented as a strategy to modify food choices and reward-related eating behaviours, but short-term studies have produced equivocal findings.

OBJECTIVE

To longitudinally assess the effect of a smartphone-based response inhibition intervention on food reward, hedonic eating drive, and cravings in a free-living setting.

METHODS

84 adults (Mage  = 30.49, SDage  = 13.01, 52 female) with high responsivity to food cues or overweight/obesity were randomly assigned to a response inhibition training intervention (n = 45) or a control game (n = 39) at home during a training week, followed by a week with no training. Primary analyses compared groups on measures of explicit liking and implicit wanting for food of different energy densities, food cravings, and reward-related eating throughout this two-week period.

RESULTS

A reduction was observed in explicit liking and implicit wanting for energy-dense foods from baseline to post-training independent of condition (ps < .001). These changes from baseline were sustained after a 1-week latency period, also independent of condition (ps < .001). These effects coincided with similar observations of hedonic eating drive, tonic cravings, and control over cravings during the observation period (ps < .01).

CONCLUSIONS

Although significant reductions in reward-related appetite were observed, free-living response inhibition training did not offer additional benefit over a control activity. Future intervention studies with observable food intake are needed to investigate which appetitive mechanisms most reliably predict eating behaviour over time.

TRIAL REGISTRATION

Retrospectively registered with ANZCTR [ACTRN12622001502729].

Reducing binge eating through behavioral-focused versus emotion-focused implementation intentions in patients with binge eating disorder or bulimia nervosa: An experimental approach

Binge eating disorder (BED) and bulimia nervosa (BN) are characterized by recurrent binge eating, episodes of consuming large amounts of food in a discrete period of time associated with a loss of control. Implementation intentions are explicit if-then plans that engender goal-directed action, and rely less on cognitive control than standard treatment options. In a sample with BED and BN, we compared two implementation intention conditions to a control condition. In the behavior-focused condition, implementation intentions targeted binge eating behaviors. In the emotion-focused condition, implementation intentions targeted negative affect preceding binge eating. In the control condition, only goal intentions were set. Each condition comprised three sessions. Participants kept food diaries for four weeks. Compared to the control condition both implementation intention conditions showed significant and large reductions of binge eating that persisted for six months. Effects did not differ between the behavior-focused and emotion-focused implementation intention conditions. These results demonstrate that three sessions on implementation intention formation can lead to long-term reductions in binge eating in patients with BED or BN. Learning how to form implementation intentions seems a recommendable addition to the current standard treatment. Future research could investigate the added value of fully personalized implementation intentions. CLINICAL TRIAL REGISTRATION NUMBER: NL52600.068.15.

When not responding to food changes food value: The role of timing

Establishing behavior change toward appetitive foods can be crucial to improve people's health. Food go/no-go training (GNG), in which people respond to some food items and not to other food items depending on the presentation of a go or no-go cue, is a means to establish behavior change. GNG changes the perceived value of food items and food consumption. After GNG, no-go items are rated as less attractive than go and/or untrained items, an empirical phenomenon called the NoGo-devaluation-effect. This effect is not always found, however. One theory-based explanation for these inconsistent results may be found in the timing of the go and no-go cues, which is also inconsistent across studies. Hence, in the present work we conducted two experiments to examine the possible role of go and no-go cue presentation timing in eliciting the NoGo-devaluation-effect. In Experiment 1, we presented the food items before the presentation of go/no-go cues, whereas we reversed this order in Experiment 2. As predicted, the NoGo-devaluation-effect was obtained in Experiment 1. This effect was absent in Experiment 2. Moreover, recognition memory for stimulus-action contingencies moderated the devaluation effect in Experiment 1, but not in Experiment 2. These results show that NoGo devaluation is dependent on the timing of the NoGo cue, which has theoretical and applied implications for understanding how and when go/no-go training influences food consumption. We propose that the value of food items is updated during go/no-go training to minimize prediction errors, and that this updating process is boosted by attention.

A randomised controlled feasibility study of food-related computerised attention training versus mindfulness training and waiting-list control for adults with overweight or obesity: the FOCUS study

BACKGROUND

In a feasibility randomised controlled trial in people with overweight/obesity with and without binge eating disorder (BED) symptoms, we assessed eight weekly sessions of attention bias modification training (ABMT) and mindfulness training (MT) versus waiting list (WL) and explored potential mechanisms.

METHODS

45 participants were randomly allocated to one of three trial arms. Primary outcomes were recruitment, retention and treatment adherence rates. Secondary outcomes included measures of eating behaviour, mood, attention and treatment acceptability. Assessments were conducted at baseline, post-intervention (week 8), and follow-up (week 12).

RESULTS

Participant retention at follow-up was 84.5% across groups. Session completion rates in the laboratory were 87% for ABMT and 94% for MT, but home practice was much poorer for ABMT. Changes in BMI and body composition were small between groups and there was a medium size BMI reduction in the MT group at follow-up. Effect sizes of eating disorder symptom changes were not greater for either intervention group compared to WL, but favoured ABMT compared to MT. Hedonic hunger and mindful eating scores favoured MT compared to ABMT and WL. ABMT reduced attention biases towards high-calorie food cues, which correlated with lower objective binge eating days at post-intervention. No significant changes were observed in the MT, or WL conditions.

CONCLUSIONS

Both ABMT and MT have potential value as adjuncts in the treatment of obesity and BED, and a larger clinical trial appears feasible and indicated.

TRIAL REGISTRATION

ISRCTN Registry, ISRCTN15745838. Registered on 22 May 2018.

Process Analyses of Impulsive Behavior in Binge-Eating Disorder During the Randomized Controlled IMPULS Trial

Impulsivity represents a risk factor for patients with binge-eating disorder, and we therefore investigated the treatment process of impulsive behaviors including binge-eating episodes in the randomized controlled IMPULS trial. Using 8 weekly online questionnaires throughout the assessment period, we compared 41 patients participating in the IMPULS program, which emphasized impulsive eating behavior (IG), with 39 control patients who received no intervention (CG). We assessed the frequency of binge eating, other impulsive behaviors, situations in which such behaviors could be inhibited, and the execution of alternative behaviors. Results indicate a stronger binge-eating reduction in the IG compared to the CG at the fifth, seventh, and eighth treatment weeks. Overall, both groups reduced other impulsive behaviors. They did not differ in the amount of inhibited impulsive behaviors and showed similar alternative behaviors, "distraction" most frequently used. IG patients evaluated the IMPULS program as very helpful. The stronger reduction of binge eating in the IG and positive evaluation of the treatment indicate a specific treatment effect regarding impulsive eating behavior. The reduction of other impulsive behaviors across both groups, and the initial reduction of binge eating within the CG, could be explained by an increased degree of self-observation.

Attention bias modification add-on to inpatient treatment for young women with anorexia nervosa-A randomized controlled trial

Patients with anorexia nervosa (AN) display elevated anxiety and attention biases (ABs) in threat processing. Attention bias modification treatment (ABMT) is considered promising for anxiety disorders, but its potential for AN is limited. In this study, 154 young women hospitalised because of AN were assigned to ED-related and anxiety-related threat stimuli, or to a non-ABMT intervention control condition in a randomized control trial. Hundred-and-ten patients completed the study. ABMT was an add-on to the regular inpatient treatment. Research participants completed two pretreatment training sessions and eight biweekly sessions of ABMT. AB, ED-related symptoms, depression, anxiety and stress were assessed before and after ABMT in the research groups, and, similarly, 5 weeks apart, in the controls. We found that despite the different patterns of change in AB between the three groups following ABMT, the reduction in AB, or the between-group differences in AB-reduction, were not significant. While the severity of ED-symptoms, depression, anxiety and stress was reduced following ABMT, or control condition, in all groups, there were no between-group differences in these changes. Changes in AB were not correlated with baseline and pre-post-treatment changes in ED-related and comorbid symptomatology. Methodological and inpatient treatment-related considerations may explain our negative ABMT-related results.

Explicit and Implicit Devaluation Effects of Food-Specific Response Inhibition Training

The overvaluation of reward-associated stimuli such as energy-dense foods can drive compulsive eating behaviours, including overeating. Previous research has shown that training individuals to inhibit their responses towards appetitive stimuli can lead to their devaluation, providing a potential avenue for behaviour change. Over two preregistered experiments, we investigated whether training participants to inhibit their responses to specific foods would be effective in reducing their evaluations when these were assessed using both explicit and implicit measures. Participants completed an online session of go/no-go training with energy-dense foods that were consistently associated with either responding (go) or inhibiting a response (no-go). An 'explicit' devaluation effect was expected as a reduction in self-reported liking from pre-to post-training for no-go items compared to both go items and foods that were not presented during training (untrained items). An 'implicit' devaluation effect was then measured using the affective priming paradigm, by comparing differences in reaction times for congruent and incongruent trials (i.e., priming effects) between food primes. Experiment 1 revealed conclusive evidence for small-to-medium devaluation effects both in terms of explicit ratings and priming effects. We also observed that the priming effect for no-go items was close to zero. Experiment 2 successfully replicated most of the preregistered and exploratory outcomes from Experiment 1 except for the priming effect for untrained items. Potential explanations for this discrepancy are discussed but overall, these findings provide further support for a devaluation effect of response inhibition training. To our knowledge, our study provides the first evidence that training-induced devaluation can potentially be captured by affective priming measures, but more research is needed to further assess their sensitivity before they can be used to elucidate the mechanisms of action underlying devaluation effects.

Identifying disrupted biological factors and patient-tailored interventions for chronic fatigue in adolescents and young adults with Q-Fever Fatigue Syndrome, Chronic Fatigue Syndrome and Juvenile Idiopathic Arthritis (QFS-study): study protocol for a randomized controlled trial with single-subject experimental case series design

Background

Chronic fatigue with a debilitating effect on daily life is a frequently reported symptom among adolescents and young adults with a history of Q-fever infection (QFS). Persisting fatigue after infection may have a biological origin with psychological and social factors contributing to the disease phenotype. This is consistent with the biopsychosocial framework, which considers fatigue to be the result of a complex interaction between biological, psychological, and social factors. In line, similar manifestations of chronic fatigue are observed in chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) and juvenile idiopathic arthritis (JIA). Cognitive behavioral therapy is often recommended as treatment for chronic fatigue, considering its effectiveness on the group level. However, not everybody benefits on the individual level. More treatment success at the individual level might be achieved with patient-tailored treatments that incorporate the biopsychosocial framework.

Methods

In addition to biological assessments of blood, stool, saliva, and hair, the QFS-study consists of a randomized controlled trial (RCT) in which a single-subject experimental case series (N=1) design will be implemented using Experience Sampling Methodology in fatigued adolescents and young adults with QFS, CFS/ME, and JIA (aged 12–29). With the RCT design, the effectiveness of patient-tailored PROfeel lifestyle advices will be compared against generic dietary advices in reducing fatigue severity at the group level. Pre-post analyses will be conducted to determine relevance of intervention order. By means of the N=1 design, effectiveness of both advices will be measured at the individual level.

Discussion

The QFS-study is a comprehensive study exploring disrupted biological factors and patient-tailored lifestyle advices as intervention in adolescent and young adults with QFS and similar manifestations of chronic fatigue. Practical or operational issues are expected during the study, but can be overcome through innovative study design, statistical approaches, and recruitment strategies. Ultimately, the study aims to contribute to biological research and (personalized) treatment in QFS and similar manifestations of chronic fatigue.

Trial registration

Trial NL8789. Registered July 21, 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06620-2.

Exploring acute and non-specific effects of mobile app-based response inhibition training on food evaluation and intake

Previous studies have demonstrated that response inhibition training can modify the appeal of palatable and energy-dense foods, thus serving as a potential intervention for weight management, via changes in food selection and intake. However, empirical findings of efficacy have been inconsistent across studies due to heterogenous approaches to measuring salient appetitive outcomes, training implementation strategies, and sample recruitment. Systematic assessment of both affective and motivational components of food reward may help characterise to what extent devaluation can be generalised to nutritionally similar foods post-training. In this mixed factorial experiment, a non-clinical, adult sample completed time-matched single sessions with mobile app-based response inhibition training and control tasks of short (12 min; n = 27) or long (20 min; n = 25) duration. Participants were assessed on two discrete facets of food reward pre- and post-training: pleasure (i.e., explicit liking) and desire (i.e., implicit wanting) for non-specific (i.e., novel) food stimuli differing in energy-density. Consumption of snacks categorised by energy density was also assessed in a laboratory ad libitum taste test post-training. No significant differences were found between intervention and control sessions on explicit liking or implicit wanting for non-specific energy-dense foods. Moreover, participants ate a similar volume of snack foods during both sessions. Training duration did not significantly moderate differences between intervention and control sessions in primary outcomes. Variance between intervention and control sessions in chocolate intake and frequency of choice for energy-dense foods, but not explicit liking, was associated with a higher BMI. Methodological and theoretical implications for appropriate intervention implementation and underlying mechanisms, respectively, are discussed.

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.

Effects of implementation intentions on subthreshold binge eating

Binge eating disorder (BED) and bulimia nervosa (BN) are characterized by binge eating. Frequently related to negative affect, binge eating is considered unwanted eating behavior. It is often preceded by a shift away from the goal of a healthy eating pattern. Implementation intentions are 'if-then' plans that may prevent such shifts in goals. In a students' sample with subthreshold binge eating, two implementation intention conditions were compared to a control condition in which only goals were formed. In the behavior-focused condition, implementation intentions targeted binge eating; in the emotion-focused condition, implementation intentions targeted negative affect preceding binge eating. All participants received three sessions and kept food diaries for four weeks, followed by a post-test and a one-month, three-months, and six-months follow-up. Compared to the control condition, both implementation intention conditions showed significant and large reductions in binge eating lasting for six months. Effects did not differ between both implementation intention conditions. Three implementation intention sessions reduced subthreshold binge eating. This continued for six months after the final session. Contrary to expectations, behavior-focused and emotion-focused implementation intentions were equally effective, possibly due to other triggers than negative affect. Future research should address their usefulness in BED and BN.

Devaluation of NoGo stimuli is both robust and fragile

Consistently not responding to stimuli during go/no-go training leads to lower evaluations of these NoGo stimuli. How this NoGo-devaluation-effect can be explained has remained unclear. Here, we ran three experiments to test the hypothesis that people form stimulus-stop-associations during the training, which predict the strength of the devaluation-effect. In Experiment 1, we tried to simultaneously measure the stimulus-stop-associations and NoGo-devaluation, but we failed to find these effects. In Experiment 2, we measured NoGo-devaluation with established procedures from previous work, and stimulus-stop-associations with a novel separate task. Results revealed a clear NoGo-devaluation-effect, which remained visible across multiple rating blocks. Interestingly, this devaluation-effect disappeared when stimulus-stop-associations were measured before stimulus evaluations, and there was no evidence supporting the formation of the stimulus-stop-associations. In Experiment 3, we found evidence for the acquisition of stimulus-stop-associations using an established task from previous work, but this time we found no subsequent NoGo-devaluation-effect. The present research suggests that the NoGo-devaluation-effect and stimulus-stop-associations can be found with standard established procedures, but that these effects are very sensitive to alterations of the experimental protocol. Furthermore, we failed to find evidence for both effects within the same experimental protocol, which has important theoretical and applied implications.

Targeting binge eating in bulimia nervosa and binge eating disorder using inhibitory control training and implementation intentions: a feasibility trial

BACKGROUND

This trial examined the feasibility, acceptability, and effect sizes of clinical outcomes of an intervention that combines inhibitory control training (ICT) and implementation intentions (if-then planning) to target binge eating and eating disorder psychopathology.

METHODS

Seventy-eight adult participants with bulimia nervosa or binge eating disorder were randomly allocated to receive food-specific, or general, ICT and if-then planning for 4 weeks.

RESULTS

Recruitment and retention rates at 4 weeks (97.5% and 79.5%, respectively) met the pre-set cut-offs. The pre-set adherence to the intervention was met for the ICT sessions (84.6%), but not for if-then planning (53.4%). Binge eating frequency and eating disorder psychopathology decreased in both intervention groups at post-intervention (4 weeks) and follow-up (8 weeks), with moderate to large effect sizes. There was a tendency for greater reductions in binge eating frequency and eating disorders psychopathology (i.e. larger effect sizes) in the food-specific intervention group. Across both groups, ICT and if-then planning were associated with small-to-moderate reductions in high energy-dense food valuation (post-intervention), food approach (post-intervention and follow-up), anxiety (follow-up), and depression (follow-up). Participants indicated that both interventions were acceptable.

CONCLUSIONS

The study findings reveal that combined ICT and if-then planning is associated with reductions in binge eating frequency and eating disorder psychopathology and that the feasibility of ICT is promising, while improvements to if-then planning condition may be needed.

Does concurrent self-administered transcranial direct current stimulation and attention bias modification training improve symptoms of binge eating disorder? Protocol for the TANDEM feasibility randomized controlled trial

BACKGROUND

Binge eating disorder (BED) is a common and disabling problem associated with impaired cognitive control. Preliminary studies show that brain-directed treatments, including transcranial direct current stimulation (tDCS) and attention bias modification training (ABMT), improve cognitive control and alleviate symptoms of BED. When combined, tDCS may enhance the effects of ABMT, and vice versa, thereby improving treatment outcomes.

METHODS

This protocol describes a feasibility single-blind randomized sham-controlled trial of concurrent self-administered tDCS and ABMT in adults with BED (The TANDEM Trial). Eighty adults with BED will be randomly assigned to one of four groups: ABMT with real or sham self-administered tDCS, ABMT only, or waiting list control. In the treatment arms, participants will complete 10-sessions of their allocated intervention over 2-3 weeks. Outcomes will be assessed at baseline (T0), immediately post treatment (T1), and 6 weeks after end of treatment (T2), and at comparable timepoints for participants in the waitlist control group. Feasibility will be evaluated by assessing recruitment/retention rates and blinding success. Acceptability will be assessed quantitatively via participant ratings and qualitatively via semi-structured interviews. Episodes of binge eating at follow-up will be the primary clinical outcome and rate ratios from Poisson regression will be reported. Secondary outcomes will assess changes in ED and general psychopathology, attention bias toward high calorie foods, and executive function.

DISCUSSION

It is hoped that data from the trial will contribute to the development of neurobiologically informed treatments for BED, provide insights into the potential use of at-home variants of tDCS, and inform the design of future large scale trials.

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.

The ironic effects of dietary restraint in situations that undermine self-regulation

Dietary restraint, defined as the cognitive effort to restrict eating, can paradoxically make individuals more susceptible to unhealthy eating when their ability to self-regulate is threatened. Past experiments have found that, in situations that elicit low self-control and/or unhealthy cravings, participants with higher dietary restraint eat more than those with lower restraint. However, these relationships have never been examined in a free-living environment. The current daily diary study examined if dietary restraint would exacerbate the associations between poor self-control and unhealthy cravings with overconsumption, namely, eating more than usual and binge eating. College women (N = 121, M age = 19) reported their restrained eating behavior and completed seven daily surveys. Multilevel analyses showed a significant interaction between dietary restraint and daily self-control on eating more than usual (b = -0.13, p = .001) and binge eating (b = -0.22, p < .001). Lower daily self-control was associated with eating more than usual and with more binge eating that day, but only among women with higher dietary restraint. Dietary restraint also moderated the effect of cravings on eating more than usual (b = 0.10, p = .007); this relationship was stronger for women with higher restraint. Stronger cravings were associated with more binge eating regardless of restraint. Results suggest that situations that undermine self-control are more strongly associated with overeating among those with higher dietary restraint. Findings can inform strategies to reduce overconsumption among restrained eaters.

Self-regulatory behaviour change techniques in interventions to promote healthy eating, physical activity, or weight loss: a meta-review

Poor quality diet, physical inactivity, and obesity are prevalent, covariant risk factors for chronic disease, suggesting that behaviour change techniques (BCTs) that effectively change one risk factor might also improve the others. To examine that question, registered meta-review CRD42019128444 synthesised evidence from 30 meta-analyses published between 2007 and 2017 aggregating data from 409,185 participants to evaluate whether inclusion of 14 self-regulatory BCTs in health promotion interventions was associated with greater improvements in outcomes. Study populations and review quality varied, with minimal overlap among summarised studies. AMSTAR-2 ratings averaged 37.31% (SD = 16.21%; range 8.33-75%). All BCTs were examined in at least one meta-analysis; goal setting and self-monitoring were evaluated in 18 and 20 reviews, respectively. No BCT was consistently related to improved outcomes. Although results might indicate that BCTs fail to benefit diet and activity self-regulation, we suggest that a Type 3 error occurred, whereby the meta-analytic research design implemented to analyse effects of multi-component intervention trials designed for a different purpose was mismatched to the question of how BCTs affect health outcomes. An understanding of independent and interactive effects of individual BCTs on different health outcomes and populations is needed urgently to ground a cumulative science of behaviour change.

Attentional bias modification for chocolate: Sham-n training as a new control group

Although attentional bias modification has been shown effective in several appetitive domains, results have been mixed. A major contributor seems to be the choice of control condition. The aim of the present study was to compare attentional bias modification for chocolate against a new control condition, sham-n (neutral or no-contingency) training. Using a modified dot probe protocol, participants (N = 192; 17–30 years) were randomly trained to attend to chocolate pictures, avoid chocolate pictures, or received sham-n training. In the attend and avoid conditions, stimulus pairs consisted of one chocolate and one non-chocolate picture, and probes replaced most often (90/10) chocolate or non-chocolate pictures, respectively. In the sham-n training condition, stimulus pairs consisted of two chocolate or two non-chocolate pictures, and probes replaced pictures within pairs with equal frequency (50/50). Attentional bias for chocolate increased following attend training, decreased following avoidance training, and did not change following sham-n training. The findings clearly demonstrate that both attend and avoidance training alter (in opposite direction) attentional bias for chocolate, whereas sham-n training is inert. This makes sham-n training particularly promising for use in clinical samples who tend to show strong initial biases.

Can sweet food-specific inhibitory control training via a mobile application improve eating behavior in children with obesity?

OBJECTIVES

Consumption of excess sugar, a common energy-dense nutrient-poor food, is a risk factor for obesity in school-aged children. Food-specific inhibition training, where responses to palatable food stimuli, such as sweet foods, are consistently and repeatedly inhibited, reduces sweet food intake in adults. However, no studies have yet examined the effectiveness of inhibitory control training specifically targeting sweet foods among children with high sugar cravings. We examined whether sweet food-specific inhibitory control training (SF-ICT), administered via a mobile app, reduced choice and consumption of sweet foods, and weight in a sample of children aged 7-11 with overweight or obesity and who had high sugar cravings (N = 46).

DESIGN

This study was designed as a 2 × 3 between-within design.

METHODS

Participants were randomly allocated to a single-blind design with two conditions: they either received 7 sessions of active or control go/no-go training in which either sweet foods or non-food cues were paired with no-go signals. Participants' weight, sweet food choice, and consumption were measured pre and post-training, and at three-month follow-up.

RESULTS

The results revealed that participants in the active group showed a significant reduction in sweet food choice and intake from pre to post-training relative to the control group. The effects of the training on reducing sweet food intake persisted over the 3-month follow-up No significant changes in weight loss were observed.

CONCLUSIONS

These results provide preliminary evidence that sweet food-specific inhibitory control training (SF-ICT) via a mobile app is effective in modifying eating behavior among children with excessive consumption of sugary foods. Further research is required to clarify under what conditions the benefits of training would expand to weight loss.

Attitudes, Habits, and Behavior Change

Efforts to guide peoples' behavior toward environmental sustainability, good health, or new products have emphasized informational and attitude change strategies. There is evidence that changing attitudes leads to changes in behavior, yet this approach takes insufficient account of the nature and operation of habits, which form boundary conditions for attitude-directed interventions. Integration of research on attitudes and habits might enable investigators to identify when and how behavior change strategies will be most effective. How might attitudinally driven behavior change be consolidated into lasting habits? How do habits protect the individual against the vicissitudes of attitudes and temptations and promote goal achievement? How might attitudinal approaches aiming to change habits be improved by capitalizing on habit discontinuities and strategic planning? When and how might changing or creating habit architecture shape habits directly? A systematic approach to these questions might help move behavior change efforts from attitude change strategies to habit change strategies. Expected final online publication date for the Annual Review of Psychology, Volume 73 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Applying the Science of Habit Formation to Evidence-Based Psychological Treatments for Mental Illness

Habits affect nearly every aspect of our physical and mental health. Although the science of habit formation has long been of interest to psychological scientists across disciplines, we propose that applications to clinical psychological science have been insufficiently explored. In particular, evidence-based psychological treatments (EBPTs) are interventions targeting psychological processes that cause and/or maintain mental illness and that have been developed and evaluated scientifically. An implicit goal of EBPTs is to disrupt unwanted habits and develop desired habits. However, there has been insufficient attention given to habit-formation principles, theories, and measures in the development and delivery of EBTPs. Herein we consider whether outcomes following an EBPT would greatly improve if the basic science of habit formation were more fully leveraged. We distill six ingredients that are central to habit formation and demonstrate how these ingredients are relevant to EBPTs. We highlight practice points and an agenda for future research. We propose that there is an urgent need for research to guide the application of the science of habit formation and disruption to the complex "real-life" habits that are the essence of EBPTs.

Effect of community-based nutritional counseling intervention on children's eating habits

AIM

This study aimed to assess the outcome of community-based nutritional counseling interventions on eating habits of rural-dwelling children.

METHODS

A group-randomized trial design was used in this study. A total of 108 rural-dwelling children from a community in the Enugu North agricultural zone, Enugu State, who participated in the study. The children were randomly assigned to 2 groups: the treatment group (n = 54) and the no-treatment control group (n = 54). The child eating behavior questionnaire was used for data collection. Parents of the participating children within each study group completed the child eating behavior questionnaire at 3 time points. The data collected were analyzed using an independent sample t test at a probability level of .05.

RESULT

The outcome of the study showed that the children's eating habits in the treatment group improved positively following the community-based nutritional counseling intervention. The positive gain from exposure to the community-based nutritional counseling intervention program was sustained during follow-up for children in the treatment group compared with the no-treatment group.

CONCLUSION

The community-based nutrition counseling intervention carried out among children in rural communities had a positive adjustment in children's eating habits. The intervention requires the constant collaboration of professional childhood educators, caregivers, home economists, school staff, healthcare specialists, families, and the children themselves. Furthermore, there is a need for future long-term evaluations of the effects of community-based nutritional counseling interventions on children's nutrition and eating habits.

Targeting executive function for weight loss in adults with overweight or obesity

Obesity is associated with a multitude of negative health sequalae. Behavioral weight loss (BWL) is currently the recommended behavioral treatment for obesity; however, it is not effective for approximately half of the individuals who participate. BWL requires individuals to carry out many tasks requiring executive function (EF; i.e., higher order cognitive functions such as planning and problem solving) in order to be successful. Growing research supports that lower EF may be associated with attenuated weight loss following BWL, and targeting EF in treatment could improve outcomes. This paper aims to describe the rationale for the development of Novel Executive Function Training for Obesity (NEXT), which adapts Compensatory Cognitive Training to be delivered in conjunction with BWL. We summarize evidence relating EF to obesity and reduced weight loss following BWL, as well as the past success of cognitive training on EF. Then we describe the treatment model for NEXT followed by initial data suggesting that NEXT is feasible and acceptable and may impact EF and weight. Obesity treatments incorporating cognitive training, especially those that train compensatory strategies, may improve weight-loss outcomes and provide a more durable treatment than traditional interventions, but larger randomized control trials are necessary.

Food-related inhibitory control training reduces food liking but not snacking frequency or weight in a large healthy adult sample

Inhibitory control training has recently been used as an intervention to aid healthy eating and encourage weight loss. The aim of this pre-registered study was to explore the effects of training on food liking, food consumption and weight loss in a large (n = 366), predominantly healthy-weight sample. Participants received four training sessions within a week, in which they had to inhibit their responses to either energy-dense foods (active group) or non-food images (control group). Subjective food ratings, food consumption frequency and weight were measured pre- and post-training. At two-weeks post-training, the active group reported a greater reduction in liking for energy-dense foods, compared to the control group. Active participants also reported a significantly greater increase in healthy food liking, immediately post-training, relative to the control group. There was no statistically significant difference between groups for the change in consumption of trained foods or for weight loss. These findings are partially consistent with previous research conducted in smaller, more overweight samples. Exploratory analyses suggest that some effects of training may be driven by awareness effects. Methodological differences across findings and avenues for future investigation are discussed.

Reconsolidation of a post-ingestive nutrient memory requires mTOR in the central amygdala

The central control of feeding behavior and metabolic homeostasis has been proposed to involve a form of post-ingestive nutrient learning independent of the gustatory value of food. However, after such learning, it is unknown which brain regions or circuits are activated to retrieve the stored memory and whether this memory undergoes reconsolidation that depends on protein synthesis after its reactivation through retrieval. In the present study, using a conditioned-flavor-preference paradigm by associating flavors with intra-gastric infusion of glucose to minimize the evaluation of the taste of food, we show that retrieval of the post-ingestive nutrient-conditioned flavor memory stimulates multiple brain regions in mice, including the central nucleus of the amygdala (CeA). Moreover, memory retrieval activated the mammalian target of rapamycin complex 1 (mTORC1) in the CeA, while site-specific or systemic inhibition of mTORC1 immediately after retrieval prevented the subsequent expression of the post-ingestive nutrient-associated flavor memory, leading to a long-lasting suppression of reinstatement. Taken together, our findings suggest that the reconsolidation process of a post-ingestive nutrient memory modulates food preferences.

Bridging executive function and disinhibited eating among youth: A network analysis

OBJECTIVE

Poorer executive function (EF) has been linked to disinhibited eating in youth, suggesting poor EF predisposes toward obesity, yet the specific nature and extent of interconnections between facets of these domains is unclear. Network analysis provides a promising framework for elucidating the relationship between poor EF and disinhibited eating, and offers insights into potential maintenance processes.

METHOD

Among youth ages 8-17 years, a regularized partial correlation network of EF and disinhibited eating facets was estimated to examine expected influence centrality and bridge expected influence. Computerized neurocognitive tasks assessed EF variables, including decision-making, general and food-related inhibitory control, delayed gratification, cognitive flexibility, and working memory. Disinhibited eating variables included total carbohydrate-fat intake at a laboratory test meal and self-reported eating in the absence of hunger, emotional eating, and loss-of-control eating severity.

RESULTS

In the current sample (N = 248; Mage = 12.5; 54.8% female; 43.5% non-Hispanic White; 25.8% non-Hispanic Black; BMI %ile = 65.8 ± 27.8), emotional eating in response to depressive symptoms emerged as a central symptom in the network. Carbohydrate-fat intake had the highest bridge expected influence and was most strongly connected to general inhibitory control (part r = .14).

DISCUSSION

The link between general inhibitory control and objective palatable food intake may be particularly salient in maintaining maladaptive eating behavior. Interventions targeting behavioral disinhibition may disrupt associations among a network of disinhibited eating facets in youth and should be targets for longitudinal research.

Food-related impulsivity assessed by longitudinal laboratory tasks is reduced in patients with binge eating disorder in a randomized controlled trial

Food-related impulsivity, i.e. a food-related attentional bias proposed to be due to increased reward sensitivity and diminished inhibitory control, has been cross-sectionally associated with binge eating disorder. To analyze changes in food-related impulsivity, we implemented longitudinal analyses of objective laboratory tasks in a randomized controlled trial called IMPULS. Patients who attended an impulsivity-focused group intervention (IG N = 31) and control patients who did not take part in the intervention (CG N = 25) were compared before (T0) and after the intervention period (T1) and at three months follow-up (T2). Patients’ impulsive gaze behavior towards food vs. neutral stimuli was measured in two eye tracking paradigms, one addressing reward sensitivity and another addressing inhibitory control. Initial fixations of food vs. neutral stimuli were increased at T0 (IG: p = .014, CG: p = .001), but not at T1 and T2 in IG (T1: p = .178, T2: p = .203) and in CG after Bonferroni correction only at T2 (T1: p = .031, T2: p = .002). Patients from IG increased dwell time on neutral stimuli at T1 contrary to patients from CG (p = .016) and rated the presented food stimuli as less positive (e.g. pleasantness p < .001 at T1 and T2). A possible explanation for this observation is reduced reward sensitivity, which implies a short-term treatment effect. Both groups showed improvement in inhibiting eye movements towards food and neutral stimuli over time (i.e. first saccade errors overall p < .001, second saccade errors overall p < .003). This could indicate increased inhibitory control due to training effects from the study paradigm. The results suggest that food-related impulsivity represents an underlying mechanism of BED and that it is modifiable by cognitive behavioral interventions.

A systematic review of event-related potentials as outcome measures of attention bias modification

Attention bias modification (ABM) was initially developed with the goal of reducing attentional bias to threat-and subsequently anxious symptoms-in individuals with heightened anxiety. Although controversial, ABM appears to be generally effective in achieving this goal. Yet, the primary outcome measure of ABM (i.e., the reaction time-based differences score) has poor reliability and temporal resolution, which limits the inferences that can be drawn. In contrast, event-related potentials (ERPs) have superior reliability as well as temporal resolution and may therefore be better outcome measures of ABM. In this review, I systematically assess the research using ERPs as outcome measures in ABM protocols. I focus on the extent to which the ERPs modified by ABM represent earlier or later stages of information processing. In addition, I explore the extent to which ABM produces near and/or far transfer of learning effects on ERP measures. The reviewed literature suggests that ERPs are promising outcome measures of ABM. ABM modulates the effects of affective stimuli on posterior visually evoked ERPs (i.e., P1) as well as ERPs at anterior electrodes (i.e., P2, N2, and ERN). Based on the state of the field, several directions for future research are identified.

Mood-induced changes in the cortical processing of food images in bulimia nervosa

BACKGROUND

Negative mood often triggers binge eating in bulimia nervosa (BN). We investigated motivational salience as a possible underlying mechanism using event-related potentials (ERPs) as indicators of motivated attention allocation (P300) and sustained processing (LPP).

METHODS

We collected ERPs (P300: 350-400 ms; LPP: 600-1000 ms) from 21 women with full-syndrome or partially remitted BN and 21 healthy women (HC), matched for age and body mass index. Idiosyncratic negative and neutral situations were used to induce corresponding mood states (counterbalanced), before participants viewed images of high- and low-calorie foods and neutral objects, and provided ratings for pleasantness and desire to eat.

RESULTS

P300 was larger for foods than objects; LPP was largest for high-calorie foods, followed by low-calorie foods, then objects. The BN group showed an increased desire to eat high-calorie foods under negative mood and stronger mood induction effects on ERPs than the HC group, with generally reduced P300 and a small increase in LPP for high-calorie foods. Effects were limited to circumscribed electrode positions. Exploratory analyses showed clearer effects when comparing high vs. low emotional eaters.

CONCLUSION

We argue that negative mood decreased the availability of cognitive resources (decreased P300) in BN, thereby facilitating disinhibition and food cravings (increased desire-to-eat ratings). Increased sustained processing might be linked to emotional eating tendencies rather than BN pathology per se, and reflect approach motivation, conflict, or regulatory processes. Negative mood appears to induce complex changes in food image processing, whose understanding may contribute to the development of tailored interventions in the future.

From cognitive targets to symptom reduction: overview of attention and interpretation bias modification research

Cognitive bias modification (CBM) is a class of mechanised psychological interventions designed to target specific aberrant cognitive processes considered key in the aetiology and/or maintenance of specific psychiatric disorders. In this review, we outline a multistage translational process that allows tracking progress in CBM research. This process involves four steps: (1) the identification of reliable cognitive targets and establishing their association with specific disorders; (2) clinical translations designed to rectify the identified cognitive targets; (3) verification of effective target engagement and (4) testing of clinical utility in randomised controlled trials. Through the prism of this multistage process, we review progress in clinical CBM research in two cognitive domains: attention and interpretation; in six psychiatric conditions: anxiety disorders, major depressive disorder, post-traumatic stress disorder, addictive disorders, eating disorders and obsessive-compulsive disorder. The review highlights achievement as well as shortcomings of the CBM approach en route to becoming a recognised evidence-supported therapy for these disorders.

Targeting automatic processes to reduce unhealthy behaviours: a process framework

While previous frameworks to address health behaviours through targeting underlying automatic processes have stimulated an improved understanding of related interventions, deciding between intervention strategies often remains essentially arbitrary and atheoretical. Making considered decisions has likely been hampered by the lack of a framework that guides the selection of different intervention strategies targeting automatic processes to reduce unhealthy behaviours. We propose a process framework to fulfil this need, building upon the process model of emotion regulation. This framework differentiates types of intervention strategies along the timeline of the unfolding automatic response, distinguishing between three broad classes of intervention strategies - direct antecedent, indirect antecedent, and response-focused. Antecedent-focused strategies aim to prevent the exposure to or activation of automatic responses directly through the avoidance of unwanted stimulus-response associations (i.e., situation modification or situation-specific response selection), or indirectly through automatising self-control (i.e., attentional deployment or cognitive change). Response-focused strategies aim to directly downregulate automatic unwanted responses (i.e., response modulation). Three main working hypotheses derived from this process framework provide practical guidance for selecting interventions, but await direct testing in future studies.

Food-related attentional bias and its associations with appetitive motivation and body weight: A systematic review and meta-analysis

Theoretical models suggest that food-related visual attentional bias (AB) may be related to appetitive motivational states and individual differences in body weight; however, findings in this area are equivocal. We conducted a systematic review and series of meta-analyses to determine if there is a positive association between food-related AB and: (1.) body mass index (BMI) (number of effect sizes (k) = 110), (2.) hunger (k = 98), (3.) subjective craving for food (k = 35), and (4.) food intake (k = 44). Food-related AB was robustly associated with craving (r = 0.134 (95% CI 0.061, 0.208); p < .001), food intake (r = 0.085 (95% CI 0.038, 0.132); p < .001), and hunger (r = 0.048 (95% CI 0.016, 0.079); p = .003), but these correlations were small. Food-related AB was unrelated to BMI (r = 0.008 (95% CI -0.020, 0.035); p = .583) and this result was not moderated by type of food stimuli, method of AB assessment, or the subcomponent of AB that was examined. Furthermore, in a between-groups analysis (k = 22) which directly compared participants with overweight/obesity to healthy-weight control groups, there was no evidence for an effect of weight status on food-related AB (Hedge's g = 0.104, (95% CI -0.050, 0.258); p = .186). Taken together, these findings suggest that food-related AB is sensitive to changes in the motivational value of food, but is unrelated to individual differences in body weight. Our findings question the traditional view of AB as a trait-like index of preoccupation with food and have implications for novel theoretical perspectives on the role of food AB in appetite control and obesity.

Exploring Changes in Event-Related Potentials After a Feasibility Trial of Inhibitory Training for Bulimia Nervosa and Binge Eating Disorder

In a feasibility trial comparing two forms of combined inhibitory control training and goal planning (i.e., food-specific and general) among patients with bulimia nervosa (BN) and binge eating disorder (BED), we found evidence of symptomatic benefit, with stronger effects among participants receiving a food-specific intervention. The aim of the present study was to examine changes in behavioral outcomes and event-related potentials (ERPs; N2 and P3 amplitudes) from baseline to post-intervention that might suggest the mechanisms underpinning these effects. Fifty-five participants completed go/no-go tasks during two electroencephalography (EEG) sessions, at baseline and post-intervention. The go/no-go task included "go" cues to low energy-dense foods and non-foods, and "no-go" cues to high energy-dense foods and non-foods. Datasets with poor signal quality and/or outliers were excluded, leaving 48 participants (N = 24 BN; N = 24 BED) in the analyses. Participants allocated to the food-specific, compared to the general intervention group, showed significantly greater reductions in reaction time to low energy-dense foods, compared to non-foods, by post-intervention. Commission errors significantly increased from baseline to post-intervention, regardless of stimulus type (food vs. non-food) and intervention group (food-specific vs. general). There were no significant changes in omission errors. P3 amplitudes to "no-go" cues marginally, but non-significantly, decreased by post-intervention, but there was no significant interaction with stimulus type (high energy-dense food vs. non-food) or intervention group (food-specific vs. general). There were no significant changes in N2 amplitudes to "no-go" cues, N2 amplitudes to "go" cues, or P3 amplitudes to "go" cues from baseline to post-intervention. Training effects were only marginally captured by these event-related potentials. We discuss limitations to the task paradigm, including its two-choice nature, ease of completion, and validity, and give recommendations for future research exploring ERPs using inhibitory control paradigms.

A pilot study investigating the influence of oxytocin on attentional bias to food images in women with bulimia nervosa or binge eating disorder

BACKGROUND

Previous research has found that exogenous oxytocin administration has the potential to modulate attentional biases in women with anorexia nervosa. Recent work has indicated that attentional biases to food may reinforce the recurrent binge eating behaviour characterising bulimia nervosa and binge eating disorder. To date, however, no study has yet investigated the effect of oxytocin on attentional biases to palatable food in women with bulimia nervosa and binge eating disorder.

METHODS

The present study employed a single-session cross-over design to test the hypothesis that a divided dose of 64 IU of intranasal oxytocin, administered as one intranasal dose of 40 IU of oxytocin followed by a top-up of 24 IU of oxytocin 80 minutes later, vs placebo administration administered in the same dosing schedule would reduce attentional biases towards food images in a dot probe task. We hypothesised that oxytocin administration would reduce vigilance towards food to a greater degree in women with bulimia nervosa or binge eating disorder vs healthy comparison women. Twenty-five women with bulimia nervosa or binge eating disorder and 27 comparison women without history of an eating disorder were recruited to take part in the study.

RESULTS

In contrast to our hypothesis, there was no main effect of diagnosis on attentional bias to food (fixed effect = 5.70, P = 0.363), nor a significant interaction between diagnosis and drug condition (fixed effect =-14.80, P = 0.645). There was a main effect of drug condition, such that oxytocin increased vigilance towards food vs neutral images in the dot probe task (fixed effect = 10.42, P = 0.044). A correlation analysis revealed that this effect was moderated by attentional bias in the placebo condition, such that greater avoidance of food stimuli in the placebo condition was associated with a greater increase in vigilance induced by oxytocin.

CONCLUSIONS

The findings of the present study add to a mixed body of literature investigating the therapeutic effects of oxytocin in women. Future research would benefit from dose-response studies investigating the optimal dose of oxytocin for modulating the attentional processing of palatable food in populations with eating disorders.

Adherence as a predictor of dropout in Internet-based guided self-help for adults with binge-eating disorder and overweight or obesity

OBJECTIVE

Internet-based guided self-help (GSH-I) is an efficacious treatment for adults with binge-eating disorder (BED) and overweight or obesity. Although broadly accessible, high dropout from GSH-I has been reported. However, little is known about the factors explaining dropout from GSH-I, including patients' adherence to treatment.

METHOD

Within a randomized trial on the treatment of BED, adherence to 4-month GSH-I was objectively assessed in N = 89 patients with BED and overweight or obesity. Objective adherence and subjective treatment evaluation were evaluated as predictors of dropout from GSH-I, defined as having accessed 5 or less of 11 modules. Cutoffs with optimal sensitivity and specificity were derived using Receiver Operating Characteristics curves analysis, and baseline sociodemographic and clinical correlates were determined.

RESULTS

According to our definition, n = 22 (24.7%) patients were defined as dropouts. Results of the full logistic regression model accounted for 72% of the variance in dropout and all objective adherence parameters (i.e., number of messages exchanged, days with a completed food diary, and days spent per module), but not patients' subjective GSH-I evaluation significantly predicted dropout. Specifically, not completing the food diary in week 7 had maximized sensitivity and specificity in predicting dropout. Patients' body mass index was positively associated with the number of messages exchanged between patients and coaches. No other associations between baseline variables and objective adherence were found.

DISCUSSION

Patients at risk for dropout from GSH-I can be reliably identified via monitoring of objective adherence and may be provided with additional interventions to prevent dropout.

Self-regulation mechanisms in health behavior change: a systematic meta-review of meta-analyses, 2006-2017

Self-regulation is one primary mechanism in interventions for health behavior change and has been examined in numerous recent meta-analyses. This pre-registered meta-review (PROSPERO CRD42017074018) examined Mmeta-analyses of any intervention and health behavior/outcome were eligible if they quantitatively assessed self-regulation and appeared between January 2006 and August 2017. In total, 66 meta-analyses were ultimately eligible; 27% reported a protocol, 11% used GRADE; 58% focused on RCTs. Reviews satisfied only a moderate number of items on the AMSTAR 2 (M = 45.45%, SD = 29.57%). Only 6% of meta-analyses directly examined whether changes in self-regulation predicted the behavior change (i.e., self-efficacy and physical activity, l = 2; frequency of self-monitoring and goal attainment, l = 1; cognitive bias modification and addiction, l = 1). Meta-analyses more routinely assessed self-regulation by comparing the efficacy of intervention components (97%), such as those from behavior change taxonomies. Meta-analyses that focused on intervention components identified several as successful, including personalized feedback, goal setting, and self-monitoring; however, none were consistently successful in that each worked only for some health behaviors and with particular populations. Some components had inconclusive evidence, given that they were only examined in low- quality reviews. Future reviewers should utilize advanced methods to assess mechanisms, and study authors should report hypothesized mechanisms to facilitate synthesis.

Study protocol of a randomised controlled feasibility study of food-related computerised attention training versus mindfulness training and waiting-list control for adults with overweight or obesity

Background

Obesity is a highly prevalent condition with multiple adverse health consequences. Widely available first-line treatments for obesity, such as dietary and other lifestyle interventions, typically have only short-term effects. Thus, new treatment approaches are needed. Novel interventions such as Attention Bias Modification Training (ABMT) and mindfulness-based interventions focus on modifying different maladaptive cognitive patterns typically present in people with obesity (e.g. attention bias to food cues); however, their mechanisms of action remain largely unknown. We describe the theoretical basis and the rationale for a study protocol of a feasibility randomised controlled trial (RCT) comparing two attention trainings (ABMT vs Mindfulness Training [MT]) in people with overweight or obesity. The aim of this study is to inform the development of a large-scale RCT in relation to acceptability and attendance rates and to identify preliminary evidence for the interventions’ clinical efficacy and potential underlying mechanisms.

Design

Forty-five adults who are either overweight or obese (minimum body mass index of 25 kg/m²) will be randomly allocated to receive eight sessions over eight weeks of either computerised ABMT or MT or be on a waiting list. Clinical and cognitive outcomes will be assessed at baseline, post-treatment (8 weeks) and follow-up (12 weeks post-randomisation). These include mood, body composition and attention biases. Credibility and acceptability of the trainings will be assessed using questionnaires, and recruitment and retention rates will be recorded.

Discussion

Findings will inform the feasibility of developing a large-scale RCT that takes into consideration effect sizes for primary outcome measures and the acceptability of the design. The study will also provide preliminary evidence on the clinical efficacy of two different attention trainings for people with obesity and associated underlying mechanisms.

Trial registration

ISRCTN Registry, ISRCTN15745838. Registered on 22 May 2018. 

Food related attention bias modification training for anorexia nervosa and its potential underpinning mechanisms

Treatment outcomes in anorexia nervosa (AN) remain suboptimal, evidencing the need for better and more targeted treatments. Whilst the aetiology of AN is complex, cognitive processes such as attention bias (AB) have been proposed to contribute to maintaining food restriction behaviour. Attention bias modification raining (ABMT) has been investigated in other eating disorders (EDs) such as binge eating disorder (BED) as a means of modifying AB for food and of changing eating behaviour. Promising findings have been reported, but the mechanisms underlying ABMT are poorly understood. We hypothesise that in AN, ABMT has the potential to modify maladaptive eating behaviours related to anxiety around food and eating and propose two mechanistic models; (1) ABMT increases general attentional control (which will improve control over disorder-relevant thoughts) or (2) ABMT promotes stimulus re-evaluation. In this second case, the effects of ABMT might arise via changes in the subjective value of food stimuli (i.e. reward processing) or via habituation, with both resulting in a reduced threat response. Investigating the clinical potential of ABMT in AN holds the promise of a novel, evidence-based adjunctive treatment approach. Importantly, understanding ABMT's underlying mechanisms will help tailor treatment protocols and improve understanding of the cognitive characteristics of AN and other EDs.

Threat and benign interpretation bias might not be a unidimensional construct

The tendency for individuals to interpret ambiguous information in a threatening way is theorised to maintain anxiety disorders. Recent findings suggest that positive and negative interpretation biases may have unique effects. This study tested the relationships between threat and benign biases with state and trait anxiety and quality of life, and whether individual differences moderate these relationships. N = 699 individuals with elevated trait anxiety symptoms completed web-based measures of interpretation bias, trait anxiety, state anxiety, and quality of life. Results demonstrated that threat interpretations predicted state anxiety, trait anxiety, and quality of life. Benign interpretations also predicted quality of life. However, benign interpretations only weakly (or not at all) predicted state and trait anxiety. Individual differences (e.g. gender, race, ethnicity, age) did not moderate findings. Results emphasise the need to consider benign and threat biases separately, both in cognitive models of anxiety and experimental designs.

Cognitive and environmental interventions to encourage healthy eating: evidence-based recommendations for public health policy

Policymakers are focused on reducing the public health burden of obesity. The UK average percentage of adults classified as obese is 26%, which is double that of the global average. Over a third of UK adults report using at least one weight management aid. Yet, many people still struggle to change their diet-related behaviour, despite having the awareness, intention and capability to do so. This 'intention-behaviour gap' may be because most existing dietary-choice interventions focus on individual decision-making, ignoring the effects of environmental cues on human behaviour. Behaviour change interventions that 'nudge' people into making healthier choices by modifying the food environment have been shown to be effective. However, this type of intervention is typically challenging for policymakers to implement for economic, ethical and public accessibility reasons. To overcome these concerns, policymakers should consider 'boosting' interventions. Boosting involves enhancing competences that help people make decisions consistent with their goals. Here, we outline cognitive training as a boosting intervention to tackle obesity. We synthesize the evidence for one type of cognitive training (go/no-go training) that may be effective at modifying food-related decisions and reducing body weight. We offer evidence-based recommendations for an obesity-focused Public Health Wales behaviour change programme.