Attention bias for chocolate increases chocolate consumption--an attention bias modification study

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.

The associations between attentional bias to food cues, parent-report appetitive traits, and concurrent adiposity among adolescents

OBJECTIVE

To assess whether attentional bias to food cues and appetitive traits are independently and interactively associated with adiposity in adolescents.

METHOD

Eighty-five adolescents, 14-17-years had their attentional bias to food images measured in a sated state by computing eye tracking measures of attention (first fixation duration, cumulative fixation duration) to food and control distractor images that bordered a computer game. Parents reported adolescent appetitive traits including the food approach domains of enjoyment of food, food responsiveness, emotional overeating, and the food avoidance domains of satiety responsiveness and emotional overeating through the Children's Eating Behavior Questionnaire.

RESULTS

First fixation bias to food cues was positively associated with enjoyment of food, and negatively associated with satiety responsiveness. In a series of regression models adjusted for relevant covariates, first fixation bias to food cues (β = 0.83, p = 0.007), higher food responsiveness (β = 0.74, p < 0.001), higher emotional overeating (β = 0.51, p = 0.002), and a composite appetite score (β = 1.42, p < 0.001) were each significantly associated with greater BMI z-scores. In models assessing the interactive effects between attentional bias and appetitive traits, higher first fixation bias to food cues interacted synergistically with food responsiveness and emotional overeating in relation to BMI z-score. A synergistic interaction between first fixation bias to food cues and the composite appetite score in relation to BMI z-score was also observed.

CONCLUSION

Individuals with high attentional bias to food cues and obesogenic appetitive traits may be particularly susceptible to weight gain.

A study of intentional inhibition of food stimuli among female restricted eaters

Restrictive eating is the propensity to restrict food consumption to control body weight. Most previous studies have focused on reactive inhibition induced by external cessation signals. Individuals usually engage in intentional inhibition, an internal form of inhibitory control that arises spontaneously in the absence of an explicit external inhibitory signal. However, there has been no clear research on intentional inhibition in restricted eaters. Therefore, the Go/No-Go/Choose experimental paradigm was used in this study to investigate the performance of intentional inhibition among restrained and unrestrained eaters under general stimuli, food stimuli, and food context conditions. The findings showed that only when food stimuli were present did the intentional inhibition of restricted and non-restricted eaters differ. In contrast to non-restricted eaters, restricted eaters significantly inhibit high-calorie foods in favor of low-calorie ones. There was no difference in intentional inhibition responses between the two groups in the non-food-related or food-context conditions, indicating that the intentional inhibition process was specific to restricted/non-restricted eaters.

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.

An Attentional Bias Modification Task, through Virtual Reality and Eye-Tracking Technologies, to Enhance the Treatment of Anorexia Nervosa

Mirror exposure therapies (METs) have been shown to be effective in reducing body image disturbances through the habituation process. Virtual reality (VR) combined with eye-tracking techniques can provide innovative solutions to some of METs’ limitations reported with patients with anorexia nervosa (AN), especially the negative influence of body-related attentional bias (AB). This pilot study aimed to assess the preliminary efficacy of a new VR-based AB modification task (ABMT) among healthy women and the procedure’s user experience. AB levels towards weight- and non-weight-related body parts, using complete fixation time (CFT) and number of fixations (NF), were assessed throughout the ABMT procedure (300 trials). The user experience was evaluated at the end of the procedure. The results showed that VR-based ABMT was effective in reducing AB significantly after 150 trials for both CFT- and NF-based measures, although 225 trials were necessary to get the same result for women with an NF initially more oriented towards weight-related body parts. Overall, the software received a “C-rating” on a scale from “A” (most usable) to “F” (least usable). These results provide evidence of the opportunity to use a VR-based ABMT procedure to reduce AB and improve existing treatments for AN.

Spatiotemporal profile of altered neural reactivity to food images in obesity: Reward system is altered automatically and predicts efficacy of weight loss intervention

Introduction

Obesity presents a significant public health problem. Brain plays a central role in etiology and maintenance of obesity. Prior neuroimaging studies have found that individuals with obesity exhibit altered neural responses to images of food within the brain reward system and related brain networks. However, little is known about the dynamics of these neural responses or their relationship to later weight change. In particular, it is unknown if in obesity, the altered reward response to food images emerges early and automatically, or later, in the controlled stage of processing. It also remains unclear if the pretreatment reward system reactivity to food images is predictive of subsequent weight loss intervention outcome.

Methods

In this study, we presented high-calorie and low-calorie food, and nonfood images to individuals with obesity, who were then prescribed lifestyle changes, and matched normal-weight controls, and examined neural reactivity using magnetoencephalography (MEG). We performed whole-brain analysis to explore and characterize large-scale dynamics of brain systems affected in obesity, and tested two specific hypotheses: (1) in obese individuals, the altered reward system reactivity to food images occurs early and automatically, and (2) pretreatment reward system reactivity predicts the outcome of lifestyle weight loss intervention, with reduced activity associated with successful weight loss.

Results

We identified a distributed set of brain regions and their precise temporal dynamics that showed altered response patterns in obesity. Specifically, we found reduced neural reactivity to food images in brain networks of reward and cognitive control, and elevated reactivity in regions of attentional control and visual processing. The hypoactivity in reward system emerged early, in the automatic stage of processing (< 150 ms post-stimulus). Reduced reward and attention responsivity, and elevated neural cognitive control were predictive of weight loss after six months in treatment.

Discussion

In summary, we have identified, for the first time with high temporal resolution, the large-scale dynamics of brain reactivity to food images in obese versus normal-weight individuals, and have confirmed both our hypotheses. These findings have important implications for our understanding of neurocognition and eating behavior in obesity, and can facilitate development of novel integrated treatment strategies, including tailored cognitive-behavioral and pharmacological therapies.

Dynamic attentional bias for pictorial and textual food cues in the visual search paradigm

Previous studies have found that individuals have an attentional bias for food cues, which may be related to the energy level or the type of stimulus (e.g., pictorial or textual food cues) of the food cues. However, the available evidence is inconsistent, and there is no consensus about how the type of stimulus and food energy modulate food-related attentional bias. Searching for food is one of the most important daily behaviors. In this study, a modified visual search paradigm was used to explore the attentional bias for food cues, and eye movements were recorded. Food cues consisted of both food words and food pictures with different energy levels (i.e., high- and low-calorie foods). The results showed that there was an attentional avoidance in the early stage but a later-stage attentional approach for all food cues in the pictorial condition. This was especially true for high-calorie food pictures. Participants showed a later-stage conflicting attentional bias for foods with different energy levels in the textual condition. They showed an attentional approach to high-calorie food words but an attentional avoidance of low-calorie food words. These data show that food-related attentional bias varied along with different time courses, which was also modulated by the type of stimulus and food energy. These findings regarding dynamic attentional bias could be explained using the Goal Conflict Model of eating behavior.

Efficacy of a food response and attention training treatment for obesity: A randomized placebo controlled trial

Elevated brain reward and attention region response, and weaker inhibitory region response to high-calorie foods has predicted future weight gain, suggesting that an intervention that reduces reward and attention region response and increases inhibitory region response to such foods might reduce overeating. We conducted a randomized controlled trial to test whether a multi-faceted food response and attention training protocol with personalized high- and low-calorie food images would reduce body fat and valuation and reward region response to high-calorie foods compared to a placebo control training protocol with non-food images in an effort to replicate findings from two past trials. Participants were community-recruited adults with overweight/obesity (N = 179; M age = 27.7 ± 7.0) who completed assessments at pretest, posttest, 3-month, 6-month, and 12-month follow-ups. Participants randomized to the food response inhibition and attention training showed significantly greater increases in palatability ratings of low-calorie foods than controls (d = 0.27) at posttest, but did not show body fat loss, reductions in palatability ratings and monetary valuation, or reward region response, to high-calorie foods. The lack of expected effects appears to be related to weaker learning compared to the learning in past trials, potentially because we used more heterogenous high-calorie and low-calorie food images in the present training.

Efficacy of a combined food-response inhibition and attention training for weight loss

This Current Opinion in Behavioral Sciences article reviews trials that evaluated an obesity treatment that combines response-inhibition training with high-calorie foods and training designed to reduce attention for high-calorie foods. Two randomized controlled trials suggest that food-response inhibition and attention training produced significant body-fat loss, along with a reduction in valuation of, and reward-region response to, high-calorie foods. However, these effects did not emerge in a third trial, potentially because this trial used more heterogeneous food images, which reduced inhibition learning and attentional learning. Collectively, results suggest that food-response inhibition and attention training can devalue high-calorie foods and result in weight loss, but only if a homogeneous set of high-calorie and low-calorie food images is used.

Exploring Mindfulness and Mindful Eating and Visual Attention Towards Food Cues: Preliminary Findings

Continual exposure to energy dense foods is suggested to promote overeating and obesity. The aim of the present research was to explore whether or not mindfulness could reduce visual attention towards food cues. In two laboratory studies, participants with a normal weight range completed an eye-tracking paradigm, and their eye-movements were recorded. In study 1, participants were exposed to either mindfulness meditation or a control condition, and their eye-movements towards low energy density (LED) vs high energy density (HED) food cues were measured. In study 2, participants were assigned to a mindful eating condition using a Mindful Construal Diary (MCD) or a control condition, and their eye-movements towards LED or HED food vs. non-food cues were recorded. In study 1, participants in the mindfulness meditation condition had greater attention duration towards LED food cues, whilst those in the control condition exhibited greater attention duration towards HED food cues. In study 2, there were no significant differences in the maintenance of attentional biases towards food cues between the two conditions. Mindfulness meditation may be beneficial in increasing attention towards LED food cues. Future research should further explore the effect of mindfulness and mindful eating on visual attention towards food cues with people who suffer from excess weight or have obesity, and also within naturalistic settings.

Choice Hygiene for "Consumer Neuroscientists"? Ethical Considerations and Proposals for Future Endeavours

Is the use of psychological and neuroscientific methods for neuromarketing research always aligned with the principles of ethical research practice? Some neuromarketing endeavours have passed from informing consumers about available options, to helping to market as many products to consumers as possible. Needs are being engineered, using knowledge about the human brain to increase consumption further, regardless of individual, societal and environmental needs and capacities. In principle, the ground ethical principle of any scientist is to further individual, societal and environmental health and well-being with their work. If their findings can be used for the opposite, this must be part of the scientist's considerations before engaging in such research and to make sure that the risks for misuse are minimised. Against this backdrop, we provide a series of real-life examples and a non-exhaustive literature review, to discuss in what way some practices in the neuromarketing domain may violate the Helsinki Declaration of Experimentation with Human Subjects. This declaration was set out to regulate biomedical research, but has since its inception been applied internationally also to behavioural and social research. We illustrate, point by point, how these ground ethical principles should be applied also to the neuromarketing domain. Indisputably, the growth in consumption is required due to current prevalent economical models. Thus, in the final part of the paper, we discuss how alternative models may be promotable to a larger public, aided by more ethical marketing endeavours, based on neuroscientific discoveries about the human brain. We propose this as a philosophical question, a point of discussion for the future, to make neuromarketing as a discipline, fit for the future, respecting the ethical implications of this research.

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.

Neural Vulnerability Factors That Predict Future Weight Gain

PURPOSE OF REVIEW

The current article discusses five neural vulnerability theories for weight gain and reviews evidence from prospective studies using imaging and behavioral measures reflecting neural function, as well as randomized experiments with humans and animals that are consistent or inconsistent with these theories.

RECENT FINDINGS

Recent prospective imaging studies examining predictors of weight gain and response to obesity treatment, and repeated-measures imaging studies before and after weight gain and loss have advanced knowledge of etiologic processes and neural plasticity resulting from weight change. Overall, data provide strong support for the incentive sensitization theory of obesity and moderate support for the reward surfeit theory, inhibitory control deficit theory, and dynamic vulnerability model of obesity, which attempted to synthesize the former theories into a single etiologic model. Data provide little support for the reward deficit theory. Important directions for future studies are delineated.

Relationship between Dispositional Mindfulness, Psychological Health, and Diet Quality among Healthy Midlife Adults

Mindfulness, a practice of non-judgmental awareness of present experience, has been associated with reduced eating psychopathology and emotion-driven eating. However, it remains unclear whether mindfulness relates to diet quality. Thus, the purpose of this study was to examine whether dispositional mindfulness is associated with diet quality and to explore psychological factors relating dispositional mindfulness to diet quality. Community-dwelling adults (N = 406; M_age = 43.19, SD = 7.26; M_{body mass index [BMI]} = 27.08, SD = 5.28; 52% female) completed ratings of dispositional mindfulness, depressive symptoms, perceived stress, positive affect (PA), and negative affect (NA). Dietary intake was assessed using the Block Food Frequency Questionnaire, from which the 2015 Healthy Eating Index was derived. Analyses were conducted using the "lavaan" package in R with bias-corrected bootstrapped confidence intervals (BootCI). Age, sex, race, education, and BMI were entered as covariates in all models. Higher dispositional mindfulness was associated with higher diet quality (β = 0.11, p = 0.03), and this effect was mediated through lower depressive symptoms (indirect effect β = 0.06, p = 0.02, BootCI = 0.104-1.42, p = 0.03). Dispositional mindfulness was negatively correlated with perceived stress (β = -0.31, p < 0.01) and NA (β = -0.43, p < 0.01), as well as positively correlated with PA (β = -0.26, p < 0.01). However, these factors were unrelated to diet quality. These cross-sectional data provide initial evidence that dispositional mindfulness relates to diet quality among midlife adults, an effect that may be explained in part by less depressive symptomatology. Given that lifestyle behaviors in midlife are leading determinants of risk for cardiovascular disease and neurocognitive impairment in late life, interventions to enhance mindfulness in midlife may mitigate disease risk. Additional research assessing the impact of mindfulness interventions on diet quality are warranted.

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.

Pleasure or Health? The Role of Mental Simulation in Desire and Food Choices

Many times, desire possesses us and impedes us from making healthier food choices. From a grounded cognition perspective, we investigated the role of two types of mental simulation (process and outcome) in desire and food choice to understand the processes that modulate them and find strategies that encourage healthier food choices. In addition to these explicit measures, we used two implicit methods to measure approach-avoidance tendencies and visual attention. Our results showed that imagining the consumption of vice and virtue foods increased desire for the product imagined and seemed to favor the choice of a vice food. However, at an implicit level, the motivation to approach and avoid food products was neutral. Imagining the post-consumption of a vice food decreased desire for the imagined food and although it tempted people at an implicit level, it made people more prone to choose a virtue food. When a vice food was imagined, attentional bias increased for all types of food regardless of the simulation. When a virtue food was imagined, there was no effect on choice, motivation nor attentional bias. In conclusion, simply imagining certain foods is a potential solution for promoting healthier and thoughtful choices.

Laboratory-based interventions targeting food craving: A systematic review and meta-analysis

This systematic review and meta-analysis aimed to quantify the effects of laboratory-based interventions targeting specific mechanisms of food craving, to identify moderators of effects, and to qualitatively summarize findings. The study was conducted and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Sixty-nine studies were included in the quantitative synthesis, and separate meta-analyses were conducted for the outcomes self-reported craving and objective food intake. Results show small to medium positive effects across specific craving interventions on both outcomes. Effect sizes were partly moderated by intervention type. The most effective intervention regarding food intake was in sensu cue exposure. For subjective craving, the most robust evidence was found for beneficial effects of cognitive regulation strategies (ie, reappraisal, suppression, and distraction). Results further indicate that training inhibitory control through behavioral inhibition might be more effective than approach-avoidance training when considering its effect on subjective craving and food intake. People with external eating habits, overeating, or loss-of-control eating might benefit from these types of specific craving interventions. Future research should focus on long-term effects, transferability, and effectiveness in clinical samples.

Is It Possible to Train the Focus on Positive and Negative Parts of One's Own Body? A Pilot Randomized Controlled Study on Attentional Bias Modification Training

Dysfunctional body- and shape-related attentional biases are involved in the etiology and maintenance of eating disorders (ED). Various studies suggest that women, particularly those with ED diagnoses, focus on negatively evaluated parts of their own body, which leads to an increase in body dissatisfaction. The present study aims to empirically test the hypothesis that non-ED women show an attentional bias toward negative body parts and that the focus on positive and negative parts of one’s own body can be modified by attentional bias modification training based on a dot-probe task. Although several studies have measured body-related attentional biases by using pictures of participants’ own bodies, the approach of investigating attentional bias via a dot-probe task while presenting pictures of the participants’ own body parts and modifying the biased attention using such pictures is novel. Women (n = 60) rank-ordered 10 parts of their own body regarding their attractiveness. To examine and modify the attentional focus, pictures of the self-defined positive and negative parts of one’s own body were presented by means of a dot-probe task. A paired-sample t-test revealed no difference between reaction times to negative compared to positive body parts, indicating no attentional bias toward negative parts of one’s own body. A two-way ANOVA revealed a main effect of time for pictures of positive and negative parts of one’s own body, with a decrease in reaction times from pre- to post-training. However, there was no significant interaction between time and training condition concerning reaction times to positive and negative body parts. Our findings replicate previous evidence of a balanced attentional pattern regarding one’s own body in women without ED diagnoses. However, the dot-probe task failed to modify the attentional focus. As the modifiability of state body image increases with more pronounced body dissatisfaction, the next step would be to test this approach in clinical samples of women with ED diagnoses.

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. 

Cognitive bias modification for energy drink cues

Energy drink consumption is increasing worldwide, especially among young adults, and has been associated with physical and mental health problems. In two experiments, we tested the prediction that energy drink consumption is in part driven by biased cognitive processing (attentional and approach biases), with a view to modifying these to reduce consumption. Young adults (18-25 years) who regularly consume energy drinks completed the dot probe (Exp.1; N = 116) or approach-avoidance task (Exp.2; N = 110) to measure attentional and approach bias for energy drink cues, respectively. They then underwent a cognitive bias modification protocol where they were trained to direct their attention away from pictures of energy drink cans (Exp.1), or to push a joystick away from themselves in response to these pictures (Exp.2). Following a post-training assessment of attentional (Exp.1) or approach bias (Exp.2), energy drink consumption was measured by an ostensible taste test. Regular energy drink consumers showed both an attentional and an approach bias for energy drink cues. Cognitive bias modification successfully reduced both biases. However, neither attentional nor approach bias modification significantly reduced energy drink intake. The results lend some support to incentive sensitisation theory which emphasises the role of biased decision-making processes related to addictive behaviours.

Cognitive training on eating behaviour and weight loss: A meta-analysis and systematic review

Cognitive deficits play a role in the development and maintenance of overeating and obesity, and cognitive training in obesity refers to a family of interventions aimed at reducing overeating and obesity by improving these cognitive deficits. In this review, we synthesize the current literature on these issues by conducting a meta-analysis of studies investigating the effects of cognitive trainings on eating behaviour and presenting a systematic review of studies investigating the effects of cognitive trainings on weight loss. We examined 66 independent experiments that examined the effects of cognitive training aimed at reducing cognitive bias or improving executive control on eating behaviour and weight loss. Overall, inhibition training, attention bias modification training, and episodic future thinking training significantly influenced eating behaviour; however, approach/avoidance training did not significantly influence eating behaviour. Moderator analyses indicated that the effect of inhibition training on eating behaviour was moderated by training task and food novelty, the effect of approach/avoidance training was moderated by food type, and the effect of episodic future thinking training was moderated by type of episodic future thinking. Literature reviewed on cognitive training and weight loss provided preliminary support for the effects of food-specific inhibition training on weight loss from pre-intervention to post intervention. However, because most of the included studies focused on short-term outcomes in normal-weight samples, longer duration studies in clinical populations (eg, individuals with obesity) are needed to examine the generalizability of these results.

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.

Approach bias modification training in bulimia nervosa and binge-eating disorder: A pilot randomized controlled trial

OBJECTIVE

Bulimia nervosa (BN) and binge-eating disorder (BED) are associated with poorly controlled approach behavior toward food resulting in binge eating. Approach bias modification (ABM) may reduce these automatic action tendencies (i.e., approach bias) toward food and may thus decrease binge eating and related symptoms.

METHOD

A total of 56 patients with BN/BED participated in this double-blind, randomized controlled trial (RCT) comparing real and sham ABM. The real ABM condition adopted an implicit learning paradigm in which participants were trained to show avoidance behavior in response to food cues. Participants in the sham condition used a similar task but were not trained to avoid food cues. Both conditions comprised 10 training sessions within 4 weeks.

RESULTS

Participants in both groups experienced significant reductions in binge eating, eating disorder symptoms, trait food craving, and food cue reactivity. Real ABM tended to result in greater reductions in eating disorder symptoms than sham ABM. Food intake, approach bias, and attention bias toward food did not change.

DISCUSSION

This is the first RCT on ABM in eating disorders. The findings provide limited support for the efficacy of ABM in BN/BED and pose questions regarding its active ingredients and its usefulness as a stand-alone treatment for eating disorders.

Effect of dietary restraint and mood state on attentional processing of food cues

BACKGROUND AND OBJECTIVES

Research linking dietary restraint to attentional bias toward food cues has been equivocal, suggesting that dietary restraint may only influence attentional processing of food in certain contexts. The present study examined whether negative mood strengthens the association between dietary restraint and attention bias for food.

METHODS

Healthy female participants were randomized to either a neutral (n = 47) or negative mood (n = 49) induction. Participants then completed a visual search task featuring targets displayed adjacent to pictures of palatable food, musical instruments, or non-instrument filler objects. Attention bias for food was operationalized as shorter response latency when the target appeared adjacent to palatable food as compared to musical instruments. Attention bias was examined in a 2 (mood condition) × 2 (picture: food vs. instrument) × 2 (target location: match vs. mismatch) repeated measures ANCOVA, with dietary restraint as a continuous covariate and response latency as the dependent variable.

RESULTS

Though there was no evidence of an interaction between mood condition and dietary restraint, mood had an influence on attention allocation. Contrary to study hypotheses, individuals in the neutral mood condition, but not those in the negative mood condition, responded in a manner indicative of bias toward food.

LIMITATIONS

Additional research is necessary to validate the experimental task used in the present study to assess food-specific attentional bias.

CONCLUSIONS

Neutral mood may be associated with enhanced processing of palatable food cues. Critically, results do not support the hypothesized link between negative mood and attention bias for food.

Neural vulnerability factors for obesity

Multiple theories identify neural vulnerability factors that may increase risk for overeating and weight gain. Early cross-sectional neuroimaging studies were unable to determine whether aberrant neural responsivity was a risk factor for or a consequence of overeating. More recent obesity risk, prospective, repeated-measures, and experimental neuroimaging studies with humans have advanced knowledge of etiologic processes and neural plasticity resulting from overeating. Herein, we review evidence from these more rigorous human neuroimaging studies, in conjunction with behavioral measures reflecting neural function, as well as experiments with animals that investigated neural vulnerability theories for overeating. Findings provide support for the reward surfeit theory that posits that individuals at risk for obesity initially show hyper-responsivity of reward circuitry to high-calorie food tastes, which theoretically drives elevated intake of such foods. However, findings provide little support for the reward deficit theory that postulates that individuals at risk for obesity show an initial hypo-responsivity of reward circuitry that motives overeating. Further, results provide support for the incentive sensitization and dynamic vulnerability theories that propose that overconsumption of high-calorie foods results in increased reward and attention region responsivity to cues that are associated with hedonic reward from intake of these high-calorie foods via conditioning, as well as a simultaneous decrease in reward region responsivity to high-calorie food tastes. However, there is little evidence that this induced reduction in reward region response to high-calorie food tastes drives an escalation in overeating. Finally, results provide support for the theory that an initial deficit in inhibitory control and a bias for immediate reward contribute to overconsumption of high-calorie foods. Findings imply that interventions that reduce reward and attention region responsivity to food cues and increase inhibitory control should reduce overeating and excessive weight gain, an intervention theory that is receiving support in randomized trials.

Risky decision-making after exposure to a food-choice task in excess weight adolescents: Relationships with reward-related impulsivity and hunger

OBJECTIVE

To assess the effects of exposure to a food-choice task (appetizing versus healthy food) on risky decision-making by excess versus normal weight adolescents. We also analyzed the influence of food visualization on hunger levels, as well as group differences in food choices and impulsivity.

METHODS

Fifty-six adolescents (aged 13-18 years) classified as excess (n = 27) or normal (n = 29) weight participated in the study. Risky-decision-making was assessed through the Balloon Analogue Risk Task, which was administered before and after a food-choice task. We also evaluated impulsivity traits through the UPPS-P Scale, and subjective hunger levels with a visual analogue scale.

RESULTS

Adolescents with excess weight showed enhanced risky decision-making after the food-choice task compared to normal weight adolescents, as well as increased hunger levels. Furthermore, excess weight adolescents made more appetizing choices, and showed greater scores for Positive Urgency and Sensation Seeking. Reward-related impulsivity measures were positively associated with the number of appetizing choices in the food-choice task. Several associations were found between impulsivity measures, hunger levels and risk-taking variables.

CONCLUSIONS

Excess weight adolescents increased their risky-decision-making after food exposure and this augmentation was associated with the increase in hunger levels. Increased hunger levels and risk-taking after food exposure could lead to overeating. Alterations in decision-making caused by food signals may be a long-term risk factor for the development of obesity in adulthood. In modern societies, with the high availability and continuous exposure to food cues, decision-making may be a crucial factor in maintain healthy eating habits in adolescents.

Feasibility and Effectiveness of Adding an Approach Avoidance Training With Game Elements to a Residential Childhood Obesity Treatment — A Pilot Study

Childhood obesity treatment programs only result in moderate outcomes in the short term and do not reduce risk for future weight gain. Therefore, in the current study, Approach Avoidance Training (AAT) with motivational game elements will be added to an inpatient childhood obesity program with the aim of improving outcomes. Forty-one children (10–15 years) in the final months of an inpatient treatment program were randomised to either the AAT plus care-as-usual condition group or to a care-as-usual-only control group. During the 10 sessions, the children were trained to approach healthy food stimuli and to avoid unhealthy food stimuli. Treatment outcomes were child performances on tasks of AAT, implicit attitudes and attentional bias, self-report ratings on craving symptoms, and weight loss maintenance after leaving the clinic (12-week follow-up). Changes over time were not significantly different between conditions for the measures of automatic processes, craving, and weight loss maintenance. Possible accounts for the null findings, including sample size, influence of game elements, point of time in therapeutic process, limitations of the setting, and the control group are discussed. More research is needed before firm conclusions can be drawn about the clinical usefulness of CBM for weight control in childhood obesity.

Promising technological innovations in cognitive training to treat eating-related behavior

One potential reason for the suboptimal outcomes of treatments targeting appetitive behavior, such as eating and alcohol consumption, is that they do not target the implicit cognitive processes that may be driving these behaviors. Two groups of related neurocognitive processes that are robustly associated with dysregulated eating and drinking are attention bias (AB; selective attention to specific stimuli) and executive function (EF; a set of cognitive control processes such as inhibitory control, working memory, set shifting, that govern goal-directed behaviors). An increasing body of work suggests that EF and AB training programs improve regulation of appetitive behaviors, especially if trainings are frequent and sustained. However, several key challenges, such as adherence to the trainings in the long term, and overall potency of the training, remain. The current manuscript describes five technological innovations that have the potential to address difficulties related to the effectiveness and feasibility of EF and AB trainings: (1) deployment of training in the home, (2) training via smartphone, (3) gamification, (4) virtual reality, and (5) personalization. The drawbacks of these innovations, as well as areas for future research, are also discussed. The above-mentioned innovations are likely to be instrumental in the future empirical work to develop and evaluate effective EF and AB trainings for appetitive behaviors.

Can attentional bias modification inoculate people to withstand exposure to real-world food cues?

Two experiments investigated whether attentional bias modification can inoculate people to withstand exposure to real-world appetitive food cues, namely television advertisements for chocolate products. Using a modified dot probe task, undergraduate women were trained to direct their attention toward (attend) or away from (avoid) chocolate pictures. Experiment 1 (N = 178) consisted of one training session; Experiment 2 (N = 161) included 5 weekly sessions. Following training, participants viewed television advertisements of chocolate or control products. They then took part in a so-called taste test as a measure of chocolate consumption. Attentional bias for chocolate was measured before training and after viewing the advertisements, and in Experiment 2 also at 24-h and 1-week follow-up. In Experiment 2, but not Experiment 1, participants in the avoid condition showed a significant reduction in attentional bias for chocolate, regardless of whether they had been exposed to advertisements for chocolate or control products. However, this inoculation effect on attentional bias did not generalise to chocolate intake. Future research involving more extensive attentional re-training may be needed to ascertain whether the inoculation effect on attentional bias can extend to consumption, and thus help people withstand exposure to real-world palatable food cues.

Effects of Bias Modification Training in Binge Eating Disorder

Food-related attentional biases have been identified as maintaining factors in binge eating disorder (BED) as they can trigger a binge episode. Bias modification training may reduce symptoms, as it has been shown to be successful in other appetitive disorders. The aim of this study was to assess and modify food-related biases in BED. It was tested whether biases could be increased and decreased by means of a modified dot-probe paradigm, how long such bias modification persisted, and whether this affected subjective food craving. Participants were randomly assigned to a bias enhancement (attend to food stimulus) group or to a bias reduction (avoid food stimulus) group. Food-related attentional bias was found to be successfully reduced in the bias-reduction group, and effects persisted briefly. Additionally, subjective craving for food was influenced by the intervention, and possible mechanisms are discussed. Given these promising initial results, future research should investigate boundary conditions of the experimental intervention to understand how it could complement treatment of BED.

General and Food-Specific Inhibitory Control As Moderators of the Effects of the Impulsive Systems on Food Choices

The present study aimed to extend the application of the reflective-impulsive model to restrained eating and explore the effect of automatic attention (impulsive system) on food choices. Furthermore, we examined the moderating effects of general inhibitory control (G-IC) and food-specific inhibitory control (F-IC) on successful and unsuccessful restrained eaters (US-REs). Automatic attention was measured using “the EyeLink 1000,” which tracked eye movements during the process of making food choices, and G-IC and F-IC were measured using the Stop-Signal Task. The results showed that food choices were related to automatic attention and that G-IC and F-IC moderated the predictive relationship between automatic attention and food choices. Furthermore, among successful restrained eaters (S-REs), automatic attention to high caloric foods did not predict food choices, regardless of whether G-IC or F-IC was high or low. Whereas food choice was positively correlated with automatic attention among US-REs with poor F-IC, this pattern was not observed in those with poor G-IC. In conclusion, the S-REs had more effective self-management skills and their food choices were affected less by automatic attention and inhibitory control. Unsuccessful restrained eating was associated with poor F-IC (not G-IC) and greater automatic attention to high caloric foods. Thus, clinical interventions should focus on enhancing F-IC, not G-IC, and on reducing automatic attention to high caloric foods.

Cognitive training as a potential treatment for overweight and obesity: A critical review of the evidence

The aim of this review is to critically evaluate the effectiveness and candidate mechanisms of action of psychological interventions which aim to either (a) improve the capacity for self-regulatory, reflective processes or (b) reduce the impact of automatic appetitive processes, in an attempt to influence food intake and associated weight-gain. Our aim was to examine three important issues regarding each type of intervention: i) whether the intervention influenced behaviour in the laboratory, ii) whether the intervention influenced behaviour and/or body mass index in the real world, and iii) whether the proposed mechanism of action was supported by evidence. We systematically searched three commonly used databases and identified 32 articles which were relevant to at least one of these issues. The majority of studies attempted to manipulate food intake in the laboratory using associative learning paradigms, in normal-weight female participants. Most of the laboratory studies demonstrated the predicted effects of interventions on behaviour in the laboratory, but studies that attempted to translate these interventions outside of the laboratory yielded more mixed findings. The hypothesised mechanisms of action received inconsistent support across studies. We identified several limitations which may complicate interpretation of findings in this area, including heterogeneity of study methods, small sample sizes, and absence of adequate control groups. We provide recommendations for future studies that aim to develop and evaluate these promising interventions for the reduction of overweight and obesity.

Pilot test of a novel food response and attention training treatment for obesity: Brain imaging data suggest actions shape valuation

Elevated brain reward and attention region response, and weaker inhibitory region response to high-calorie food images have been found to predict future weight gain. These findings suggest that an intervention that reduces reward and attention region response and increases inhibitory control region response to such foods might reduce overeating. We conducted a randomized pilot experiment that tested the hypothesis that a multi-faceted food response and attention training with personalized high- and low-calorie food images would produce changes in behavioral and neural responses to food images and body fat compared to a control training with non-food images among community-recruited overweight/obese adults. Compared to changes observed in controls, completing the intervention was associated with significant reductions in reward and attention region response to high-calorie food images (Mean Cohen's d = 1.54), behavioral evidence of learning, reductions in palatability ratings and monetary valuation of high-calorie foods (p = 0.009, d's = 0.92), and greater body fat loss over a 4-week period (p = 0.009, d = 0.90), though body fat effects were not significant by 6-month follow-up. Results suggest that this multifaceted response and attention training intervention was associated with reduced reward and attention region responsivity to food cues, and a reduction in body fat. Because this implicit training treatment is both easy and inexpensive to deliver, and does not require top-down executive control that is necessary for negative energy balance obesity treatment, it may prove useful in treating obesity if future studies can determine how to create more enduring effects.

Automatic Approach Tendencies toward High and Low Caloric Food in Restrained Eaters: Influence of Task-Relevance and Mood

Objective: Although restrained eaters are motivated to control their weight by dieting, they are often unsuccessful in these attempts. Dual process models emphasize the importance of differentiating between controlled and automatic tendencies to approach food. This study investigated the hypothesis that heightened automatic approach tendencies in restrained eaters would be especially prominent in contexts where food is irrelevant for their current tasks. Additionally, we examined the influence of mood on the automatic tendency to approach food as a function of dietary restraint. Methods: An Affective Simon Task-manikin was administered to measure automatic approach tendencies where food is task-irrelevant, and a Stimulus Response Compatibility task (SRC) to measure automatic approach in contexts where food is task-relevant, in 92 female participants varying in dietary restraint. Prior to the task, sad, stressed, neutral, or positive mood was induced. Food intake was measured during a bogus taste task after the computer tasks. Results: Consistent with their diet goals, participants with a strong tendency to restrain their food intake showed a relatively weak approach bias toward food when food was task-relevant (SRC) and this effect was independent of mood. Restrained eaters showed a relatively strong approach bias toward food when food was task-irrelevant in the positive condition and a relatively weak approach in the sad mood. Conclusion: The weak approach bias in contexts where food is task-relevant may help high-restrained eaters to comply with their diet goal. However, the strong approach bias in contexts where food is task-irrelevant and when being in a positive mood may interfere with restrained eaters' goal of restricting food-intake.

Disparity in neural and subjective responses to food images in women with obesity and normal-weight women

OBJECTIVE

Self-reports tend to differ from objective measurements of food intake, particularly in adults with obesity; however, no studies have examined how neural responses to food (an objective measure) and subjective ratings of food differ by BMI status. This study tested normal-weight women (NWW) and women with obesity (OBW) for group differences in neural indices of attention towards food pictures, subjective ratings of these pictures, and the disparity between objective and subjective measurements.

METHODS

Twenty-two NWW (21.8 ± 1.7 kg/m² ) and 22 OBW (37.0 ± 5.7 kg/m² ) viewed food and flower pictures while late positive potential amplitude, an event-related potential, was recorded. Participants rated pictures for arousal and valence.

RESULTS

Late positive potential amplitude was larger toward food than flower pictures. OBW self-reported flower pictures as more pleasant than food; NWW showed no difference for pleasantness. There were no significant main effects or interactions for arousal. Standardized scores showed that only on subjective, but not objective, measures did OBW compared with NWW disproportionately indicate food pictures as less pleasant than flowers.

CONCLUSIONS

Compared with NWW, OBW showed larger discrepancies between neural and subjective reports of attention towards food. Inaccurate self-reports of attention towards food may reduce the efficiency of health interventions.

Training response inhibition to reduce food consumption: Mechanisms, stimulus specificity and appropriate training protocols

Training individuals to inhibit their responses towards unhealthy foods has been shown to reduce food intake relative to a control group. Here we aimed to further explore these effects by investigating the role of stimulus devaluation, training protocol, and choice of control group. Restrained eaters received either inhibition or control training using a modified version of either the stop-signal or go/no-go task. Following training we measured implicit attitudes towards food (Study 1) and food consumption (Studies 1 and 2). In Study 1 we used a modified stop-signal training task with increased demands on top-down control (using a tracking procedure and feedback to maintain competition between the stop and go processes). With this task, we found no evidence for an effect of training on implicit attitudes or food consumption, with Bayesian inferential analyses revealing substantial evidence for the null hypothesis. In Study 2 we removed the feedback in the stop-signal training to increase the rate of successful inhibition and revealed a significant effect of both stop-signal and go/no-go training on food intake (compared to double-response and go training, respectively) with a greater difference in consumption in the go/no-go task, compared with the stop-signal task. However, results from an additional passive control group suggest that training effects could be partly caused by increased consumption in the go control group whereas evidence for reduced consumption in the inhibition groups was inconclusive. Our findings therefore support evidence that inhibition training tasks with higher rates of inhibition accuracy are more effective, but prompt caution for interpreting the efficacy of laboratory-based inhibition training as an intervention for behaviour change.

Innovative Techniques for Evaluating Behavioral Nutrition Interventions

Assessing outcomes and the impact from behavioral nutrition interventions has remained challenging because of the lack of methods available beyond traditional nutrition assessment tools and techniques. With the current high global obesity and related chronic disease rates, novel methods to evaluate the impact of behavioral nutrition-based interventions are much needed. The objective of this narrative review is to describe and review the current status of knowledge as it relates to 4 different innovative methods or tools to assess behavioral nutrition interventions. Methods reviewed include 1) the assessment of stress and stress responsiveness to enhance the evaluation of nutrition interventions, 2) eye-tracking technology in nutritional interventions, 3) smartphone biosensors to assess nutrition and health-related outcomes, and 4) skin carotenoid measurements to assess fruit and vegetable intake. Specifically, the novel use of functional magnetic resonance imaging, by characterizing the brain's responsiveness to an intervention, can help researchers develop programs with greater efficacy. Similarly, if eye-tracking technology can enable researchers to get a better sense as to how participants view materials, the materials may be better tailored to create an optimal impact. The latter 2 techniques reviewed, smartphone biosensors and methods to detect skin carotenoids, can provide the research community with portable, effective, nonbiased ways to assess dietary intake and quality and more in the field. The information gained from using these types of methodologies can improve the efficacy and assessment of behavior-based nutrition interventions.

A developmental neuroscience perspective on affect-biased attention

There is growing interest regarding the impact of affect-biased attention on psychopathology. However, most of the research to date lacks a developmental approach. In the present review, we examine the role affect-biased attention plays in shaping socioemotional trajectories within a developmental neuroscience framework. We propose that affect-biased attention, particularly if stable and entrenched, acts as a developmental tether that helps sustain early socioemotional and behavioral profiles over time, placing some individuals on maladaptive developmental trajectories. Although most of the evidence is found in the anxiety literature, we suggest that these relations may operate across multiple domains of interest, including positive affect, externalizing behaviors, drug use, and eating behaviors. We also review the general mechanisms and neural correlates of affect-biased attention, as well as the current evidence for the co-development of attention and affect. Based on the reviewed literature, we propose a model that may help us better understand the nuances of affect-biased attention across development. The model may serve as a strong foundation for ongoing attempts to identify neurocognitive mechanisms and intervene with individuals at risk. Finally, we discuss open issues for future research that may help bridge existing gaps in the literature.

An open trial evaluating an attention bias modification program for overweight adults who binge eat

BACKGROUND AND OBJECTIVES

Binge eating is prevalent and is associated with significant psychiatric and medical comorbidities. To date, the most effective psychological treatments for individuals who binge eat are not effective for all patients and they do not result in significant weight loss. Dual process theories suggest that implicit factors, such as attention bias, may influence behavior, even when the behavior is in opposition to long-term goals. Attention bias modification programs have been tested in other areas of psychopathology, and could be utilized to improve outcomes for people who binge eat. Thus, the aim of this open trial was to conduct a preliminary evaluation of an attention bias modification program (ABM-Food) designed to train attention away from food cues.

METHODS

Adults who binge eat and were overweight or obese enrolled in an 8-week ABM-Food program, which consisted of one session in the lab each week and two training sessions at home. Nine participants completed the ABM-Food training program and the post-treatment assessment, and 8 completed the 3-month post-treatment assessment.

RESULTS

Results showed that the ABM-Food program is a feasible and acceptable treatment for adults who binge eat. Initial effectiveness data showed decreases in weight, eating disorder symptoms, binge eating, loss of control and responsivity to food in the environment, as well as changes in attention bias. The majority of these effects remained at the 3-month follow-up time point.

LIMITATIONS

This study is limited by the single-group open label trial, and the small sample size.

CONCLUSIONS

This open trial provides initial evidence for the feasibility, acceptability and effectiveness of ABM-Food for individuals who binge eat and are overweight or obese.

Brain dopamine and serotonin transporter binding are associated with visual attention bias for food in lean men

BACKGROUND

In rodents, the striatal dopamine (DA) system and the (hypo)thalamic serotonin (5-HT) system are involved in the regulation of feeding behavior. In lean humans, little is known about the relationship between these brain neurotransmitter systems and feeding. We studied the relationship between striatal DA transporters (DAT) and diencephalic 5-HT transporters (SERT), behavioral tasks and questionnaires, and food intake.

METHOD

We measured striatal DAT and diencephalic SERT binding with [123I]FP-CIT SPECT in 36 lean male subjects. Visual attention bias for food (detection speed and distraction time) and degree of impulsivity were measured using response-latency-based computer tasks. Craving and emotional eating were assessed with questionnaires and ratings of hunger by means of VAS scores. Food intake was assessed through a self-reported online diet journal.

RESULTS

Striatal DAT and diencephalic SERT binding negatively correlated with food detection speed (p = 0.008, r = -0.50 and p = 0.002, r = -0.57, respectively), but not with food distraction time, ratings of hunger, craving or impulsivity. Striatal DAT and diencephalic SERT binding did not correlate with free choice food intake, whereas food detection speed positively correlated with total caloric intake (p = 0.001, r = 0.60), protein intake (p = 0.01, r = 0.44), carbohydrate intake (p = 0.03, r = 0.39) and fat intake (p = 0.06, r = 0.35).

CONCLUSIONS

These results indicate a role for the central 5-HT and DA system in the regulation of visual attention bias for food, which contributes to the motivation to eat, in non-obese, healthy humans. In addition, this study confirms that food detection speed, measured with the latency-based computer task, positively correlates with total food and macronutrient intake.

Neural vulnerability factors that increase risk for future weight gain

Theorists have proposed several neural vulnerability factors that may increase overeating and consequent weight gain. Early cross-sectional imaging studies could not determine whether aberrant neural responsivity was a precursor or consequence of overeating. However, recent prospective imaging studies examining predictors of future weight gain and response to obesity treatment, and repeated-measures imaging studies before and after weight gain and loss have advanced knowledge of etiologic processes and neural plasticity resulting from weight change. The present article reviews evidence from prospective studies using imaging and behavioral measures reflecting neural function, as well as randomized experiments with humans and animals that are consistent or inconsistent with 5 neural vulnerability theories for excessive weight gain. Extant data provide strong support for the incentive sensitization theory of obesity and moderate support for the reward surfeit theory, inhibitory control deficit theory, and dynamic vulnerability model of obesity, which attempted to synthesize the former theories into a single etiologic model. However, existing data provide only minimal support for the reward deficit theory. Findings are synthesized into a new working etiologic model that is based on current scientific knowledge. Important directions for future studies, which have the potential to support or refute this working etiologic model, are delineated. (PsycINFO Database Record

Sustained effects of attentional re-training on chocolate consumption

BACKGROUND AND OBJECTIVES

Accumulating evidence shows that cognitive bias modification produces immediate changes in attentional bias for, and consumption of, rewarding substances including food. This study examined the longevity of these attentional bias modification effects.

METHODS

A modified dot probe paradigm was used to determine whether alterations in biased attentional processing of food cues, and subsequent effects on consumption, were maintained at 24-h and one-week follow-up. One hundred and forty-nine undergraduate women were trained to direct their attention toward ('attend') or away from ('avoid') food cues (i.e., pictures of chocolate). Within each group, half received a single training session, the other half completed 5 weekly training sessions.

RESULTS

Attentional bias for chocolate cues increased in the 'attend' group, and decreased in the 'avoid' group immediately post training. Participants in the 'avoid' group also ate disproportionately less of a chocolate food product in a so-called taste test than did those in the 'attend' group. Importantly, the observed re-training effects were maintained 24 h later and also one week later, but only following multiple training sessions.

LIMITATIONS

There are a number of limitations that could be addressed in future research: (a) the inclusion of a no-training control group, (b) the inclusion of a suspicion probe to detect awareness of the purpose of the taste test, and (c) the use of different tasks to assess and re-train attentional bias.

CONCLUSIONS

The results showed sustained effects of attentional re-training on attentional bias and consumption. They further demonstrate the importance of administering multiple re-training sessions in attentional bias modification protocols.