Attentional biases for food cues in overweight and individuals with obesity: a systematic review of the literature

Uncontrolled eating is associated with higher impulsiveness, risk taking and novelty-seeking

Previous studies suggest that trait disinhibition as measured by the Three Factor eating Questionnaire (TFEQ) is related to selected measures of impulsivity and risk taking. However, the factor validity of the original trait disinhibition measure has been questioned, and a revised scale of uncontrolled eating consequently developed. To date few studies have revisited the relationship between impulsivity and the uncontrolled and emotional eating scales of the revised TFEQ. In the present study, 283 participants (208 women) completed the revised TFEQ alongside a battery of measures of impulsivity and risk taking in an online study. The total and all subscale scores on the Barratt Impulsiveness Scale were significantly associated with scores on the uncontrolled, but not emotional or restrained, TFEQ scale. Likewise, risky behaviour indexed by the average number of pumps per trial on the Balloon Analogue Risk Task were also associated with uncontrolled, but not emotional or restrained, eating, and the same pattern of associations were also found for the novelty, but not intensity, subscales of the Arnetts Inventory of Sensation Seeking. Overall these data suggest that uncontrolled eating is related to wider personality traits of risky decision making, novelty seeking and wider cognitive impulsivity, which may in turn increase of future weight gain.

Beyond the modified dot-probe task: A meta-analysis of the efficacy of alternate attention bias modification tasks across domains

Attention biases towards disease-relevant cues have been implicated in numerous disorders and health conditions, such as anxiety, cancer, drug-use disorders, and chronic pain. Attention bias modification (ABM) has shown that changing attention biases can change related emotional processes. ABM most commonly uses a modified dot-probe task, which has received increasing criticism regarding its reliability and inconsistent findings. The purpose of the present review was thus to systematically review and meta-analyse alternative tasks used in ABM research. We sought to examine whether alternative tasks significantly changed attention biases and emotional outcomes, and critically examined whether relevant sample, task and intervention characteristics moderated each of these effect sizes. Seventy-four (completer n = 15,294) study level comparisons were included in the meta-analysis. Overall, alternative ABM designs had a medium effect on changing biases (g = 0.488), and a small, but significant effect on improving clinical outcomes (g = 0.117). We found this effect to be significantly larger for studies which successfully changed biases compared to those that did not. Across all tasks, it appeared that targeting engagement biases results in the largest change to attention biases. Importantly, we found tasks incorporating gaze-contingency - encouraging engagement with non-biased stimuli - show the most promise for improving emotional outcomes.

A systematic review of the effectiveness of attentional bias modification to support weight management in individuals who are overweight or obese

Attentional bias modification (ABM) is a novel cognitive-based treatment that may help individuals reduce overeating by decreasing food processing bias and food cravings. However, most empirical studies have evaluated the short-term effects of ABM in populations that have body mass indexes that are within healthy ranges; therefore, the extent to which this training method can influence eating behavior in individuals who are overweight or obese remains unclear. This systematic review explored the efficacy of ABM as a tool to support weight management for individuals who are overweight or obese. Ten studies met the inclusion criteria for the review. The findings reveal that although training is effective at manipulating attentional bias to food cues, there is limited evidence that training significantly impacted appetite and eating behaviors or led to maintained weight loss.

Goal pursuit increases more after dietary success than after dietary failure: examining conflicting theories of self-regulation using ecological momentary assessment

BACKGROUND

Maintaining a healthy body weight and reaching long-term dietary goals requires ongoing self-monitoring and behavioral adjustments. How individuals respond to successes and failures is described in models of self-regulation: while cybernetic models propose that failures lead to increased self-regulatory efforts and successes permit a reduction of such efforts, motivational models (e.g., social-cognitive theory) make opposite predictions. Here, we tested these conflicting models in an ecological momentary assessment (EMA) context and explored whether effort adjustments are related to inter-individual differences in perceived self-regulatory success in dieting (i.e., weight management).

METHODS

Using linear mixed effects models, we tested in 174 diet-interested individuals whether current day dietary success or failure (e.g., on Monday) was followed by self-regulatory effort adjustment for the next day (e.g., on Tuesday) across 14 days. Success vs. failure was operationalized with two EMA items: first, whether food intake was higher vs. lower than usual and second, whether food intake was perceived as more vs. less goal-congruent than usual. Trait-level perceived self-regulatory success in dieting was measured on a questionnaire.

RESULTS

Intended self-regulatory effort increased more strongly after days with dietary success (i.e., eating less than usual / rating intake as goal-congruent) than after days with dietary failure (i.e., eating more than usual / rating intake as goal-incongruent), especially in those individuals with lower scores on perceived self-regulatory success in dieting.

CONCLUSIONS

Findings support mechanisms proposed by social-cognitive theory, especially in unsuccessful dieters. Thus, future dietary interventions could focus on preventing the decrease in self-regulatory effort after instances of dietary failures and thereby mitigate the potential risk that a single dietary failure initiates a downward spiral into unhealthy eating.

Neuroimaging and neuroendocrine insights into food cravings and appetite interventions in obesity

This article reviews the previous studies on the distinction between food cravings and appetite, and how they are regulated by hormones and reflected in brain activity. Based on existing research, food cravings are defined as individual preferences influenced by hormones and psychological factors, which differ from appetite, as they are not necessarily related to hunger or nutritional needs. The article also evaluates the neuroimaging findings about food cravings, and interventions to reduce food cravings, such as mindfulness training, alternative sweeteners, non-invasive brain stimulation techniques, cognitive-behavioral therapy, and imaginal retraining, and points out their advantages, disadvantages, and limitations. Furthermore, the article delves into the potential future directions in the field, emphasizing the need for a neuroendocrine perspective, considerations for associated psychiatric disorders, innovative clinical interventions, and emerging therapeutic frontiers in obesity management. The article outlines the neuro-endocrine basis of food cravings, including ghrelin, leptin, melanocortin, oxytocin, glucagon-like peptide-1, baclofen, and other hormones and their brain regions of action. The article argues that food cravings are an important target for obesity, and more research is needed to explore their complex characteristics and mechanisms, and how to effectively interact with their neuro-endocrine pathways. The article provides a new perspective and approach to the prevention and treatment of obesity.

Food cue reward salience does not explain Hyperphagia in adolescents with Prader-Willi syndrome

Prader-Willi Syndrome (PWS) is characterized by hyperphagia, an extreme and persistent hunger that emerges in early childhood. We used event-related potentials (ERPs) to objectively investigate brain responses to low- and high-calorie foods, animals, and household objects in 20 satiated adolescents with PWS. Late Positive Potential (LPP) responses to food images did not differ from non-food images. Rather, we observed larger ERPs to high-calorie foods relative to animal images (p=.001) in an earlier time window. These responses correlated with greater severity of hyperphagia (p = .01). Thus, hyperphagia associated with PWS may be due to altered satiety regulation rather than increased motivational salience.

Odour-imagery ability is linked to food craving, intake, and adiposity change in humans

It is well-known that food-cue reactivity (FCR) is positively associated with body mass index (BMI)1 and weight change2, but the mechanisms underlying these relationships are incompletely understood. One prominent theory of craving posits that the elaboration of a desired substance through sensory imagery intensifies cravings, thereby promoting consumption3. Olfaction is integral to food perception, yet the ability to imagine odours varies widely4. Here we test in a basic observational study whether this large variation in olfactory imagery drives FCR strength to promote adiposity in 45 adults (23 male). We define odour-imagery ability as the extent to which imagining an odour interferes with the detection of a weak incongruent odour (the 'interference effect'5). As predicted in our preregistration, the interference effect correlates with the neural decoding of imagined, but not real, odours. These perceptual and neural measures of odour imagery are in turn associated with FCR, defined by the rated craving intensity of liked foods and cue-potentiated intake. Finally, odour imagery exerts positive indirect effects on changes in BMI and body-fat percentage over one year via its influences on FCR. These findings establish odour imagery as a driver of FCR that in turn confers risk for weight gain.

Paediatric obesity and metabolic syndrome associations with cognition and the brain in youth: Current evidence and future directions

Obesity and components of the metabolic syndrome (MetS) are associated with differences in brain structure and function and in general and food-related cognition in adults. Here, we review evidence for similar phenomena in children and adolescents, with a focus on the implications of extant research for possible underlying mechanisms and potential interventions for obesity and MetS in youth. Current evidence is limited by a relative reliance on small cross-sectional studies. However, we find that youth with obesity and MetS or MetS components show differences in brain structure, including alterations in grey matter volume and cortical thickness across brain regions subserving reward, cognitive control and other functions, as well as in white matter integrity and volume. Children with obesity and MetS components also show some evidence for hyperresponsivity of food reward regions and hyporesponsivity of cognitive control circuits during food-related tasks, altered brain responses to food tastes, and altered resting-state connectivity including between cognitive control and reward processing networks. Potential mechanisms for these findings include neuroinflammation, impaired vascular reactivity, and effects of diet and obesity on myelination and dopamine function. Future observational research using longitudinal measures, improved sampling strategies and study designs, and rigorous statistical methods, promises to further illuminate dynamic relationships and causal mechanisms. Intervention studies targeted at modifiable biological and behavioural factors associated with paediatric obesity and MetS can further inform mechanisms, as well as test whether brain and behaviour can be altered for beneficial outcomes.

Comparative efficacy of remotely delivered mindfulness-based eating awareness training versus behavioral-weight loss counseling during COVID-19

Introduction

Dysregulated eating (emotional eating, cue-elicited eating, and dietary restraint and restriction) has been linked to being overweight or obese. The present investigation used a random controlled trial (RCT) to test the differential efficacy of remotely delivered Mindfulness-Based Eating Awareness Training (MB-EAT) and Behavioral Weight Loss (BWL) counseling.

Methods

The sample was recruited through advertisements that offered help to people "with problems controlling their eating" or "interested in improving their relationship with food" (n = 135).

Results

Retention was low in both groups (42%), but not dissimilar to retention rates reported in related clinical trials delivered "in person." Among the participants who completed treatment, we found no between-group differences in any of the treatment outcomes, but participants in both groups experienced significant increases in eating-related mindfulness [Mindful Eating Questionnaire (MEQ) and awareness [Multidimensional Assessment of Interoceptive Awareness (MAIA), and significant decreases in unhealthy eating patterns [Dutch Eating Behavior Questionnaire (DEBQ); Binge Eating Scale (BES), and weight over the course of treatment. Participants in both groups also experienced increases in self-reported depression and anxiety symptoms [Hospital Anxiety and Depression Scale (HADS)], although these increases likely reflected normative changes observed in the population at large during COVID-19.

Discussion

Overall, the results suggest that dysregulated eating and weight loss intervention delivered remotely via teleconference can be effective.

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.

Odor imagery but not perception drives risk for food cue reactivity and increased adiposity

Mental imagery has been proposed to play a critical role in the amplification of cravings. Here we tested whether olfactory imagery drives food cue reactivity strength to promote adiposity in 45 healthy individuals. We measured odor perception, odor imagery ability, and food cue reactivity using self-report, perceptual testing, and neuroimaging. Adiposity was assessed at baseline and one year later. Brain responses to real and imagined odors were analyzed with univariate and multivariate decoding methods to identify pattern-based olfactory codes. We found that the accuracy of decoding imagined, but not real, odor quality correlated with a perceptual measure of odor imagery ability and with greater adiposity changes. This latter relationship was mediated by cue-potentiated craving and intake. Collectively, these findings establish odor imagery ability as a risk factor for weight gain and more specifically as a mechanism by which exposure to food cues promotes craving and overeating.

Psychological Pathways Through Which Social Norms and Social Identity Influence Eating Behavior: Testing a Conceptual Model

BACKGROUND

Although interventions frequently promote healthy eating, failing to consider psychosocial factors, such as social norms, may limit the effectiveness of these efforts. Perceived social norms are a well-documented determinant of eating behavior; however, there is limited understanding of the processes through which, and for whom, this relationship emerges. Using identity-based motivation as a theoretical framework, we present a conceptual model identifying one route through which descriptive social norms-beliefs about how others behave-predict eating behavior, and test whether this process varies across social identities (e.g., self-perceived weight status).

METHOD

Structured telephone interviews were conducted for a national sample of non-diabetic adults who identified as non-Hispanic White, non-Hispanic Black, or Mexican American (n = 990).

RESULTS

Multigroup SEM analysis comparing individuals who self-identified as overweight (versus "about the right weight" and underweight) demonstrated that perceiving descriptive social norms that people do not eat healthy foods predicted greater perceived barriers to eating healthy foods. Perceived barriers, in turn, predicted stronger beliefs that body weight is uncontrollable, and this relationship was stronger for participants who self-identified as overweight (relative to participants who did not identify as overweight). These beliefs subsequently predicted greater self-reported consumption of unhealthy foods (e.g., sweets), but did not predict consumption of fruits or vegetables.

CONCLUSIONS

This study extends our understanding of a psychosocial process that predicts consumption of unhealthy foods and underscores the importance of social identities for shaping responses to perceived norms.

The impact of racially-targeted food marketing and attentional biases on consumption in Black adolescent females with and without obesity: Pilot data from the Black Adolescent & Entertainment (BAE) study

Unhealthy food advertisements ("advertisements" hereafter referred to as "ads") are linked to poor diet and obesity, and food companies disproportionally target Black youth. Little is known about the mechanisms whereby food ads influence diet. One possibility may be racially-targeted ads that appeal to Black youth. Those with food-related attentional biases may be especially vulnerable. The objective of this project was to assess the feasibility and initial effects of a pilot study testing the influence of racially-targeted food ads and food-related attentional biases on eating behaviors among a sample of Black adolescent females. Feasibility of recruitment, retention, and procedures were examined. Participants (N = 41, 12-17y) were randomized to view a television episode clip of the Big Bang Theory embedded with either four 30-second racially-targeted food ads or neutral ads. A computer dot probe task assessed food-related attentional biases. The primary outcome was caloric consumption from a laboratory test meal. Interactions based on weight and ethnic identity were also examined. Analyses of variance and regressions were used to assess main and interaction effects. Exposure to racially-targeted food ads (versus neutral ads) did not affect energy consumption (p > .99). Although not statistically significant, adolescents with obesity consumed nearly 240 kcal more than non-overweight adolescents (p = 0.10). There were no significant preliminary effects related to food-related attentional biases or ethnic identity (ps = 0.22-0.79). Despite a non-significant interaction, these data provide preliminary support that adolescents with obesity may be particularly vulnerable to racially-targeted food ads. An adequately powered trial is necessary to further elucidate the associations among racially-targeted food ads among Black adolescent girls with obesity.

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.

Development of Chinese food picture library for inducing food cravings

Cue-induced food cravings are strong desires directed toward specific foods, usually ones with high caloric content, and can lead to overeating. However, although food cravings vary according to individual preferences for specific high-calorie food subtypes, a structured library of food craving-inducing pictures including multiple categories of high-calorie foods does not yet exist. Here, we developed and validated a picture library of Chinese foods (PLCF) consisting of five subtypes of high-calorie foods (i.e., sweets, starches, salty foods, fatty foods, and sugary drinks) to allow for more nuanced future investigations in food craving research, particularly in Chinese cultural contexts. We collected 100 food images representing these five subtypes, with four food items per subtype depicted in five high-resolution photographs each. We recruited 241 individuals with overweight or obesity to rate the food pictures based on craving, familiarity, valence, and arousal dimensions. Of these participants, 213 reported the severity of problematic eating behaviors as a clinical characteristic. Under the condition of mixing multiple subtypes of high-calorie foods, we did not observe significant differences in craving ratings for high- and low-calorie food images (p _tukey > 0.05). Then, we compared each subtype of high-calorie food images to low-calorie ones, and found craving ratings were greater for the images of salty foods and sugary drinks (ps < 0.05). Furthermore, we conducted a subgroup analysis of individuals according to whether they did or did not meet the criteria for food addiction (FA) and found that greater cravings induced by the images of high-calorie food subtypes (i.e., salty foods and sugary drinks) only appeared in the subgroup that met the FA criteria. The results show that the PLCF is practical for investigating food cravings.

Body mass index and attention bias of food cues in women: a mediation model of body weight dissatisfaction

Food attention bias could be used to indicate diet-related diseases in individuals with obesity. The purpose of this study is to explore the relationship between body mass index (BMI) and food attention bias, and the mediating role of body weight dissatisfaction (BWD) on this relationship in women. Seventy-five participants were recruited to complete a visual dot task with eye tracking. The results showed that BMI would positively predict response latency and duration bias on high-calorie foods; the relationship between BMI and response latency of high-calorie food was a complete mediation of BWD; the relationship between BMI and duration bias of high-calorie food was a complete mediation of BWD; and BWD positively predicts response latency and duration bias on high-calorie foods. These findings suggest a positive relationship between BMI and food attention bias, and the effect of a complete mediation of BWD in women.

An EEG study on the effect of being overweight on anticipatory and consummatory reward in response to pleasant taste stimuli

Two-thirds of adults in the United Kingdom currently suffer from overweight or obesity, making it one of the biggest contributors to health problems. Within the framework of the incentive sensitisation theory, it has been hypothesised that overweight people experience heightened reward anticipation when encountering cues that signal food, such as pictures and smells of food, but that they experience less reward from consuming food compared to normal-weight people. There is, however, little evidence for this prediction. Few studies test both anticipation and consumption in the same study, and even fewer with electroencephalography (EEG). This study sought to address this gap in the literature by measuring scalp activity when overweight and normal-weight people encountered cues signalling the imminent arrival of pleasant and neutral taste stimuli, and when they received these stimuli. The behavioural data showed that there was a smaller difference in valence ratings between the pleasant and neutral taste in the overweight than normal-weight group, in accordance with our hypothesis. However, contrary to our hypothesis, the groups did not differ in their electrophysiological response to taste stimuli. Instead, there was a reduction in N1 amplitude to both taste and picture cues in overweight relative to normal-weight participants. This suggests that reduced attention to cues may be a crucial factor in risk of overweight.

Using event-related potentials to study food-related cognition: An overview of methods and perspectives for future research

Electroencephalography (EEG), and the measure of event-related potentials (ERPs) in particular, are useful methods to study the cognitive and cerebral mechanisms underlying the perception and processing of food cues. Further research on these aspects is necessary to better understand how cognitive functioning may influence food choices in different populations (e.g. obese individuals, individuals with eating disorders). To help researchers in designing future studies, this article provides an overview of the methods used in the current literature on ERPs and food-related cognition. Several methodological aspects are explored to outline interesting perspectives for future research, including discussions on the main experimental tasks used, the cognitive functions assessed (e.g. inhibitory control, attentional processing), the characteristics of the participants recruited (e.g. weight status, eating behaviors), and the stimuli selected (e.g. food pictures, odors). The issues generated by some of these methodological choices are discussed, and a few guidelines are provided.

Altered Brain Structural Reorganization and Hierarchical Integrated Processing in Obesity

The brain receives sensory information about food, evaluates its desirability and value, and responds with approach or withdrawal. The evaluation process of food in the brain with obesity may involve a variety of neurocircuit abnormalities in the integration of internal and external information processing. There is a lack of consistency of the results extant reported for aberrant changes in the brain with obesity that prohibits key brain alterations to be identified. Moreover, most studies focus on the observation of neural plasticity of function or structure, and the evidence for functional and structural correlations in the neuronal plasticity process of obesity is still insufficient. The aims of this article are to explore the key neural structural regions and the hierarchical activity pattern of key structural nodes and evaluate the correlation between changes in functional modulation and eating behavior. Forty-two participants with obesity and 33 normal-weight volunteers were recruited. Gray matter volume (GMV) and Granger causality analysis (GCA) were performed using the DPARSF, CAT12, and DynamicBC toolbox. Compared with the normal weight group, the obesity group exhibited significantly increased GMV in the left parahippocampal gyrus (PG). The obesity group showed decreased causal inflow to the left PG from the left orbitofrontal cortex (OFC), right calcarine, and bilateral supplementary motor area (SMA). Decreased causal outflow to the left OFC, right precuneus, and right SMA from the left PG, as well as increased causal outflow to the left middle occipital gyrus (MOG) were observed in the obesity group. Negative correlations were found between DEBQ-External scores and causal outflow from the left PG to the left OFC, and DEBQ-Restraint scores and causal inflow from the left OFC to the left PG in the obesity group. Positive correlation was found between DEBQ-External scores and causal outflow from the left PG to the left MOG. These results show that the increased GMV in the PG may play an important role in obesity, which may be related to devalued reward system, altered behavioral inhibition, and the disengagement of attentional and visual function for external signals. These findings have important implications for understanding neural mechanisms in obesity and developing individual-tailored strategies for obesity prevention.

Intake Differences between Subsequent 24-h Dietary Recalls Create Significant Reporting Bias in Adults with Obesity

In depth understanding of the dietary patterns of individuals with obesity is needed in practice and research, in order to support dietitians and physicians in the design and implementation of nutritional management. We aimed to analyze the consistency of energy, macro-, and micronutrient reported intakes in four non-consecutive 24-h dietary recalls from 388 adults with obesity using information collected in the NutriGen Study (ClinicalTrials.gov, NCT02837367). Significant decreases were identified for reported energy and several, macro- and micronutrient intakes, between the first and subsequent 24-h recalls. Significant differences of reported intakes were identified in sensitivity analyses, suggesting that the first recall (also the only one performed on site, face-to-face) might be a point of bias. A comparison of the differences in intakes between weekend and weekday, after adjustment for false discovery rate were non-statistically significant either in male, females, or in total. To overcome this potential bias, studies should be carefully conducted, starting from the design phase, through to the analysis and interpretation phases of the study. Prior to averaging specific intakes across all sessions of reporting, a preliminary analysis must be conducted to identify if a certain time point had significant differences from all other time points and overview potential sources of bias: reporting bias, training bias, or behavioral changes could be responsible for such differences.

Food Captures Attention, but Not the Eyes: An Eye-Tracking Study on Mindset and BMI’s Impact on Attentional Capture by High-Caloric Visual Food Stimuli

Obesity is a worldwide pandemic and theories propose that attentional bias (AB) for food triggers craving and overeating, especially for people with obesity. However, empirical evidence is inconsistent, which may be due to methodological diversity and the double-sided nature of high-caloric palatable foods. That is, these foods simultaneously have a high hedonic and a low health value. So, depending on context and/or emotional state, people’s mindset while viewing foods may alternate between hedonic (taste) and health (calories) values, possibly affecting AB for food in opposite directions. This study tests how mindset and BMI (Body Mass Index) influences AB and food intake. We expect greater AB for food and more food intake in the hedonic compared to the health mindset, especially for people with obesity. Mindsets were induced using short video-clips in two sessions in counterbalanced order. Participants (35 with a healthy-weight-category BMI, 31 with obesity) performed a modified Additional Singleton paradigm where they searched for a neutral target among neutral fillers. On 90% of the trials, either a food or a neutral distractor appeared. Response latencies to the target and eye-movements to the distractor were recorded. Dependent variables included: response latencies, and eye-movement variables on the distractor: fixations (%), 1st fixation duration, dwell-time. Food intake was assessed in a bogus taste test. No significant effects emerged from the eye-movements analysis, whereas the analysis of response latencies showed an AB for food, not significantly moderated by BMI or mindset. Food intake was affected by mindset partly as expected, as participants ate more in the hedonic than in the health mindset when the hedonic mindset was induced in the second session. One AB measure (fixations) correlated positively with food intake. Finally, food captured attention – but not the eyes – and mindset affects food intake partly as expected.

Dynamic changes in the food-cue processing of obese adolescents: A controlled eye-tracking study from a dual-system perspective

Adolescent obesity is a growing global health problem. Studies have demonstrated that exposure to food cues plays a role in both the development and the persistence of obesity. Understanding how visual attention changes dynamically in response to food cues may explain how they contribute to obesity. The primary aims were to evaluate attentional bias for food cues and conduct a time-course analysis of obese adolescents' food-cue processing. We also investigated the roles of inhibition, cognitive flexibility, and eating styles in their visual attention to food stimuli. A total of 60 age- and gender-matched 12-16-year-olds (n = 30, obese group; n = 30, control group; M = 13.9 years, SD = 1.26) were included in this study's sample. The participants viewed a series of high-calorie and low-calorie food images along with nonfood images in the free exploration paradigm during eye-tracking. Time-course analysis of the proportion of fixations on images of food and high-calorie foods determined that the attentional processing of the two groups differed, especially in later stages. The obese group had higher Stroop Interference and Trail Making Test-B scores than the control group, but these executive functions' scores did not affect their proportions of fixations on food and high-calorie food images over time. Higher Perceptual Reasoning Index scores led to a decrease in the proportions of fixations on high-calorie food images over time in the obese group, and this was particularly noticeable after about 4000 ms. This study found that time-course analysis of visual attention to food cues allows us to understand how it changes dynamically over larger time intervals. Future studies should provide knowledge about maintained attention for food cues and their relationship with top-down factors in obese adolescents.

Exercise Increases Attentional Bias Towards Food Cues in Individuals Classified as Overweight to Obese

BACKGROUND

The obesity epidemic continues to be a major public health concern. Although exercise is the most common weight loss recommendation, weight loss outcomes from an exercise program are often suboptimal. The human body compensates for a large percentage of the energy expended through exercise to maintain energy homeostasis and body weight. Increases in energy intake appear to be the most impactful compensatory behavior. Research on the mechanisms driving this behavior has not been fully elucidated.

PURPOSE

To determine if exercise influences the attentional processing towards food cues (attentional bias) and inhibitory control for food cues among individuals classified as overweight to obese who do not exercise.

METHODS

Thirty adults classified as overweight to obese participated in a counterbalanced, crossover trial featuring two assessment visits on separate days separated by at least one week. Attentional bias and inhibitory control towards food cues was assessed prior to and after a bout of exercise where participants expended 500 kcal (one assessment visit) and before and after a 60 min bout of watching television (second assessment visit). Attentional bias was conceptualized as the percentage of time fixated on food cues when both food and neutral (non-food) cues were presented during a food-specific dot-probe task. Inhibitory control, specifically motor impulsivity, was assessed as percentage of inhibitory failures during a food-specific Go/NoGo task.

RESULTS

A significant condition by time effect was observed for attentional bias towards food cues, independent of hunger, whereas attentional bias towards food cues was increased pre-post exercise but not after watching TV. Inhibitory control was not affected by exercise or related to attentional bias for food cues.

CONCLUSIONS

An acute bout of exercise increased attentional bias for food cues, pointing to a mechanism that may contribute to the weight loss resistance observed with exercise. Future trials are needed to evaluate attentional bias towards food cues over a longitudinal exercise intervention.

Olfaction in the context of obesity and diabetes: Insights from animal models to humans

The olfactory system is at the crossroad between sensory processing and metabolic sensing. In addition to being the center of detection and identification of food odors, it is a sensor for most of the hormones and nutrients responsible for feeding behavior regulation. The consequences of modifications in body homeostasis, nutrient overload and alteration of this brain network in the pathological condition of food-induced obesity and type 2 diabetes are still not elucidated. The aim of this review was first to use both humans and animal studies to report on the current knowledge of the consequences of obesity and type 2 diabetes on odorant threshold and olfactory perception including identification discrimination and memory. We then discuss how olfactory processing can be modified by an alteration of the metabolic homeostasis of the organism and available elements on pharmacological treatments that regulate olfaction. We focus on data within the olfactory system but also on the interactions between the olfactory system and other brain networks impacted by metabolic diseases.

Food olfactory cues reactivity in individuals with obesity and the contribution of alexithymia

Obesity has been associated with increased reward sensitivity to food stimuli, but a few studies have addressed this issue by using odors. This study investigated whether obesity is associated with increased liking and wanting of food odors and whether alexithymia, a psychological construct characterized by diminished affective abilities, contributes to altered responsiveness to food. Liking and wanting for food and pleasant non-food odors were measured through explicit (self-report ratings) and implicit measures (heart rate and skin conductance) in 23 women with healthy weight (HW) and 20 women with overweight/obesity (OW/OB). Differently from the HW group, the OW/OB group explicitly liked food odors less than non-food odors; but, at the implicit level, there were no differences in heart rate response for both types of odors, indicating that they were equally liked. Moreover, at variance with the HW group, the OW/OB group did not exhibit increased skin conductance response for food compared to nonfood odors. Alexithymia was associated with increased implicit liking and explicit wanting of food odors, in particular in the HW group. These findings show that obesity is characterized by high levels of implicit food liking and low levels of implicit food wanting. Moreover, both affective and motivational responses to food reward seem to be affected by alexithymia, which should be taken into account by studies evaluating the effect of cue exposure intervention for obesity treatment.

Food Attention Bias: appetite comes with eating

OBJECTIVE

Cognitive interventions may be effective in weight loss. The purpose of this study was to assess if cognitive reappraisal (CR; reframing the meaning of a stimulus in order to change the resulting emotional response), can reduce food attentional bias (FAB) using the Visual Dot Probe (VDP) paradigm.

METHOD

126 participants (age 27 ± 5.8) were randomly assigned either to a CR or to a control (CN) group. After assessing baseline VDP levels for FAB, participants either wrote sentences that discourage eating fattening food or neutral sentences. Next, all participants performed the VDP post intervention. Participants also self-reported on disordered eating behaviors and their height and weight were charted. We hypothesized that CR would reduce FAB and that disordered eating would moderate the association between group and FAB.

RESULTS

FAB decreased post intervention, specifically in the CR group. The bulimia sub-scale showed an interaction between bulimic eating, time and group. Among those who were high on the bulimia scale, the CR group showed lower FAB post-intervention compared to the CN group.

DISCUSSION

This study suggests that CR may decrease the attentional bias toward high-calorie food compared to other strategies in the general population and among people with high bulimia measures, in particular. Obesity has a negative impact on many aspects of life and much research is dedicated to trying to better understand behaviors concerning obesity. People are prone to focus their attention on things that are of importance to them, such as food. When people focus their attention on food, we call this Food Attention Bias (FAB). Cognitive reappraisal (CR) interventions involve the person's conscious cognitive change of the meaning of the situation aiming to consequently change the emotional response to it, such as saying to yourself "I shouldn't eat this because I don't want to get fat". CR has been found to be helpful in lowering FAB using brain imagining techniques but has not yet been studied in cognitive processes. Our study used a Visual dot probe paradigm (VDP) to assess the efficacy of CR on lowering FAB. Two groups, one using CR and a control group were assessed twice on FAB, using the VDP paradigm. Compared to the normal condition, the CR intervention helped reduce FAB. This reduction was especially significant for people with a higher tendency for bulimic behavior. The VDP paradigm, utilizing CR. can be expanded to help build an intervention aimed at reducing FAB over time. This, in turn might bring to weight reduction. People with bulimic tendencies might especially benefit from CR interventions when dealing with weight loss.

Fluctuations in attentional bias for food and the role of executive control

Research has shown repeatedly that overweight and obesity are associated with more fluctuations in attentional bias (AB), as reflected in trial-level bias scores (TL-BS). More specifically, people with a high BMI more frequently alternate their attention towards and away from food over time. The current study proposed and tested a model on the mechanism behind the positive association between variability of AB for food and BMI. It was hypothesized that poor executive control (poor response inhibition and lower sustained attention) would be related to both higher BMI and more fluctuations in AB for food and this would, at least partly, explain the significant relationship between variability of AB for food and BMI. To test our hypotheses, 99 female participants completed both an online food dot-probe task and an online stop-signal task. It was found that response inhibition was significantly related to BMI, whereas, contrary to our hypotheses, variability of AB for food was not related to BMI nor to executive control. In conclusion, this study revealed a relation between poor inhibitory control and higher BMI. However, a role of executive control in fluctuations in attention for food could not be established.

A meta-analysis of the relationship between eating restraint, impaired cognitive control and cognitive bias to food in non-clinical samples

AIM

Food restriction is argued to be a precursor for unhealthy preoccupation with food, possibly leading to the development of an eating disorder. We updated previous meta-analyses that examined the relationship between eating restraint and deficits in either general or food-related attentional and inhibitory control. We hypothesized that inconsistencies in the literature around eating restraint, impaired cognitive control, impulsivity and cognitive biases for food could be attributed to the scale used to measure eating restraint.

METHOD

A (preregistered) subgroup meta-analysis examined whether patterns of impaired cognitive control and cognitive bias for food in predominantly healthy (non-clinical) samples differed as a function of the scale used to measure eating restraint. A series of exploratory meta-analyses were carried out for specific attentional bias tasks. In total 57 datasets were included.

RESULTS

The subgroup analysis did not provide evidence that the relationship between eating restraint and impaired or biased cognitions differed significantly as a function of restraint scale. Heterogeneity across studies was high. When examining specific attentional bias tasks there was no evidence that increased eating restraint was associated with increased attentional bias or distraction by food cues, regardless of which scale was used to measure eating restraint.

CONCLUSIONS

There is little experimental evidence for the common narrative that increased eating restraint is related to impaired cognitive control generally or increased cognitive bias for food, in non-clinical samples.

Development and Validation of the Four Facet Mindful Eating Scale (FFaMES)

OBJECTIVES

Previous mindful eating scales stress the attentional domains of eating-specific mindfulness, such as present-moment attention to homeostatic cues of hunger and satiety while discounting other important domains such as non-judgment and decentering. The purpose of the series of studies was to develop and evaluate a multifaceted mindful eating scale that assesses several domains of eating-specific mindfulness.

METHODS

A multistep process was used to construct the Four Facet Mindful Eating Scale (FFaMES). Study 1 outlined the initial scale construction and the development of a novel item pool (N = 480). Study 2 examined the internal structure of the observed variables using exploratory analysis (N = 445) and confirmatory analysis in a separate sample (N = 445). Reliability and validity were assessed in Study 3 (N = 166).

RESULTS

The final scale consists of 29 items with 4 factors: Non-Reactance, Non-Judgment, External Awareness, and Internal Awareness. The FFaMES demonstrated good internal consistency, retest reliability as well as preliminary convergent and divergent validity.

CONCLUSIONS

Our findings provide reliability evidence and initial support for the construct validity of the FFaMES and the continued study of multiple facets of eating-specific mindfulness. Future research should continue to investigate the differential effects of various aspects of eating-specific mindfulness in the prevention and treatment of obesity and its comorbidities.

The Impact of Restrictive and Non-restrictive Dietary Weight Loss Interventions on Neurobehavioral Factors Related to Body Weight Control: the Gaps and Challenges

PURPOSE OF REVIEW

Restrictive diets, such as low-calorie diets, are difficult to maintain in the long term. For this reason, their popularity has decreased compared to non-restrictive approaches, which instead promote healthy eating strategies. Since both strategies may entail different neurobiological mechanisms, this review will examine the current evidence on the effects of restrictive and non-restrictive interventions on neurobehavioral factors.

RECENT FINDINGS

Restrictive diets appear to improve eating behaviors, and the evidence reviewed argues against the notion that they may worsen the severity of binge eating. Moreover, they may lead to short-term changes in brain structure and improvements in cerebrovascular markers which, in turn, could impact eating behaviors. Non-restrictive interventions may have a positive effect on weight management and eating behaviors. However, evidence of their neural effects is scarce. Small sample sizes, short follow-ups, and the absence of control groups are limitations of the studies targeting both interventions. Rigorous long-term randomized studies are needed to examine the neurobehavioral effects of restrictive and non-restrictive approaches.

Problematic eating as an issue of habitual control

Obesity has reached alarming rates worldwide. Although many people attempt to control weight by modifying their food-related behaviours, this typically only has short-term effects and most dieters regain the weight that was lost. Why do so many people struggle to regulate their food-related behaviours? One possible explanation is that these behaviours have become habits that are not immediately sensitive to their consequences. Here we review experimental evidence for a shift to habitual control over food-related behaviours and the neural systems that control them and how this relates to difficulty changing ones' eating behavior.

Associations of somatic depressive symptoms with food attentional bias and eating behaviors

Recent evidence suggests that atypical major depressive disorder (MDD) - whose key features include the reversed somatic symptoms of hyperphagia (increased appetite) and hypersomnia (increased sleep) - is a stronger predictor of future obesity than other MDD subtypes. The mechanisms underlying this relationship are unclear. The present study sought to elucidate whether the individual symptoms of hyperphagia, hypersomnia, poor appetite, and disturbed sleep have differential relationships with food attentional bias, emotional eating, external eating, and restrained eating. This cross-sectional laboratory study involved 103 young adults without obesity (mean age = 20 years, 79% female, 26% non-White, mean BMI = 23.4 kg/m²). We measured total depressive symptom severity and individual symptoms of hyperphagia, poor appetite, and disturbed sleep using the Hopkins Symptom Checklist-20 (SCL-20) and added an item to assess hypersomnia; food attentional bias using a Food Stroop task; and self-reported eating behaviors using the Dutch Eating Behavior Questionnaire. Hyperphagia was positively associated with emotional eating but negatively associated with food attentional bias. Hypersomnia was negatively associated with emotional eating. Poor appetite was negatively associated with emotional eating. Disturbed sleep was positively associated with food attentional bias and emotional eating. An aggregate of the remaining 15 depressive symptoms (SCL-15) was positively associated with emotional and restrained eating. Our findings highlight the importance of examining the direction of somatic depressive symptoms, and they set the stage for future research to identify subgroups of people with depression at greatest risk for obesity (e.g., those with hyperphagia and/or disturbed sleep) and the mechanisms responsible for this elevated risk (e.g., emotional eating).

Differences in Food Craving in Individuals With Obesity With and Without Binge Eating Disorder

Overeating behavior is supposedly a major contributing factor to weight gain and obesity. Binge eating disorder (BED) with reoccurring episodes of excessive overeating is strongly associated with obesity. Learning models of overeating behavior and BED assume that mere confrontation with food leads to a conditioned response that is experienced as food craving. Accordingly, individuals with obesity and BED were shown to have high trait food cravings. To date, little is known about differences in state food cravings and cue reactivity at the sight of palatable food in individuals with obesity and BED compared to individuals with obesity without BED. Therefore, the aim of our study was to examine differences in cue-induced, state and trait food cravings in people with obesity with and without BED. We found that all aspects of food cravings were more prevalent in individuals with obesity and BED than in individuals without BED. By implementing a food cue reactivity paradigm, our results show that individuals with obesity with BED have more cue-induced cravings than individuals with obesity without BED. Moreover, these cue-induced cravings in individuals with obesity and BED were highest for high-fat and high-sugar foods as opposed to low-calorie foods. Thus, our results emphasize the role of increased cue reactivity and craving at the sight of palatable foods in individuals with obesity and BED. Hence, our findings support etiological models of conditioned binge eating and are in line with interventions targeting cue reactivity in BED.

Effects of Acute Alcohol Consumption on Food Intake and Pictorial Stroop Response to High-Calorie Food Cues

AIMS

We examined (a) the effect of an acute dose of alcohol on the consumption of energy-dense food and (b) on cognitive bias towards high-energy-dense food cues and (3) whether the effect of an acute dose of alcohol on the consumption of energy-dense food would be mediated by cognitive bias towards high-energy-dense food cues.

METHODS

Heavy social drinkers (n = 40) abstained from drinking for 12 hours before testing. On the test day, participants completed pre-challenge measures of alcohol and food craving, and cognitive bias towards alcohol in a placebo-controlled, double-blind design. Participants performed post-challenge measures of alcohol and food craving, ad lib energy-dense food consumption and cognitive bias.

RESULTS

We did not observe any of the hypothesized interactions between challenge condition, consumption of energy-dense food and cognitive bias towards high-energy-dense food cues.

CONCLUSIONS

Our data suggest that acute alcohol consumption does not influence the consumption of energy-dense food or cognitive bias towards high-energy-dense food cues. These findings may reflect that alcohol does not increase the appetitive value of food and food-related cues or that the measures used in this study were not sensitive to detect an effect. Further research is required to determine whether alcohol at higher doses and/or food cues that are frequently paired with alcohol intake stimulates changes in food intake and the reward value of food cues.

A Dual-Pathway Perspective on Food Choices in Adolescents: The Role of Loss of Control Over Eating

Introduction

One in three adolescents frequently consume unhealthy snacks, which is associated with negative developmental outcomes. To date, it remains unclear how intrapersonal factors account for food choices in adolescents. Guided by the dual-pathway model, the current study aimed to: (1) examine the joint contribution of inhibitory control and attentional bias in predicting unhealthy food choices in adolescents, and (2) determine whether this mechanism is more pronounced in adolescents who experience loss of control over eating (LOC).

Materials and Methods

A community sample of 80 adolescents (65% female; 10–17 years old, M_age = 13.28, SD = 1.94) was recruited. Based on a self-report questionnaire, 28.7% of this sample reported at least one episode of LOC over the past month. Food choice was assessed using a computerized food choice task. Both inhibitory control and attentional bias were measured with behavioral tasks (go/no-go and dot probe task, respectively). Binary logistic regressions were conducted to address the research questions.

Results

Inhibitory control and attentional bias did not significantly interact to predict unhealthy food choices. However, there was a significant three-way interaction between inhibitory control, attentional bias and LOC. For adolescents without LOC, the combination of poor inhibitory control and low attentional bias was significantly associated with unhealthy food choice. Surprisingly, for adolescents with LOC, there was no significant association between unhealthy food choice and inhibitory control or attentional bias.

Discussion

Dual-pathway processes do not seem to add to the explanation of food choice behavior for adolescents with LOC. For adolescents who do not experience LOC, those with poor inhibitory control combined with low attentional bias might be at particular risk for making unhealthy food choices.

A Pictorial Dot Probe Task to Assess Food-Related Attentional Bias in Youth With and Without Obesity: Overview of Indices and Evaluation of Their Reliability

Several versions of the dot probe detection task are frequently used to assess maladaptive attentional processes associated with a broad range of psychopathology and health behavior, including eating behavior and weight. However, there are serious concerns about the reliability of the indices derived from the paradigm as measurement of attentional bias toward or away from salient stimuli. The present paper gives an overview of different attentional bias indices used in psychopathology research and scrutinizes three types of indices (the traditional attentional bias score, the dynamic trial-level base scores, and the probability index) calculated from a pictorial version of the dot probe task to assess food-related attentional biases in children and youngsters with and without obesity. Correlational analyses reveal that dynamic scores (but not the traditional and probability indices) are dependent on general response speed. Reliability estimates are low for the traditional and probability indices. The higher reliability for the dynamic indices is at least partially explained by general response speed. No significant group differences between youth with and without obesity are found, and correlations with weight are also non-significant. Taken together, results cast doubt on the applicability of this specific task for both experimental and individual differences research on food-related attentional biases in youth. However, researchers are encouraged to make and test adaptations to the procedure or computational algorithm in an effort to increase psychometric quality of the task and to report psychometric characteristics of their version of the task for their specific sample.

Investigating salience strategies to counteract obesity

The investigation of the characteristics and attributes that make a brand prominent for shoppers is known as salience research. This line of study concentrates on influencing buying behaviors via the manipulation of shopping environments and food products. Such promotional strategies successfully attract massive food sales and therefore have been associated with changes in dietary patterns and the epidemic expansion of non-communicable diseases, like obesity. Marketers have empirically proven that global buying patterns are influenced by their salience strategies and techniques. However, despite the significance of such methods, empirical salience investigations have rarely been extended beyond their primary business focus to the field of health promotion. Therefore, this study is presenting a way of transferring the salience knowledge to the health promotion field in order to track dietary choices and possibly gain information to identify buying and eating behaviors connected to obesity. The salience literature from various disciplines permits to hypothesize that consumers are more likely to have unhealthy diets when food-choices and conditions are saliently manipulated. A quasi-experimental method (combining salience measures with Bayesian analysis) was used to test this proposition. The results support the hypothesis and endorse the introduced research tool. As predicted, data reflect the latest national overweight and obesity statistics and suggest that habitual unhealthy diets are more likely when salience strategies link food products to taste, social and emotional attributes. These preliminary findings encourage further investigation to enhance the method as a possible epidemiological tool.

Do Food Odors Differently Influence Cerebral Activity Depending on Weight Status? An Electroencephalography Study of Implicit Olfactory Priming Effects on the Processing of Food Pictures

Attentional automatic processes and cerebral activity may differ between individuals with different weight statuses in the presence of food stimuli (e.g. odors, pictures). In the present study, we used an implicit olfactory priming paradigm to test the influence of non-attentively perceived food odors on the cerebral activity underlying the processing of food pictures, in normal-weight, overweight, and obese adults. A pear odor and a pound cake odor were used as primes, respectively priming sweet low-energy-density foods and high-energy-density foods. Event-related potentials were recorded while the participants passively watched pictures of sweet low and high-energy-density foods, under the two priming conditions plus an odorless control condition. The amplitude and latency of several peaks were measured (P100, N100, P200, N400). As a major result, we found that weight status influences the cerebral activity underlying the processing of food cues outside of consciousness, as early as the first detectable P100 peak.

The neural substrates of subliminal attentional bias and reduced inhibition in individuals with a higher BMI: A VBM and resting state connectivity study

Previous studies have shown that individuals with overweight and obesity may experience attentional biases and reduced inhibition toward food stimuli. However, evidence is scarce as to whether the attentional bias is present even before stimuli are consciously recognized. Moreover, it is not known whether or not differences in the underlying brain morphometry and connectivity may co-occur with attentional bias and impulsivity towards food in individuals with different BMIs. To address these questions, we asked fifty-three participants (age M = 23.2, SD = 2.9, 13 males) to perform a breaking Continuous Flash Suppression (bCFS) task to measure the speed of subliminal processing, and a Go/No-Go task to measure inhibition, using food and nonfood stimuli. We collected whole-brain structural magnetic resonance images and functional resting-state activity. A higher BMI predicted slower subliminal processing of images independently of the type of stimulus (food or nonfood, p = 0.001, ε_p² = 0.17). This higher threshold of awareness is linked to lower grey matter (GM) density of key areas involved in awareness, high-level sensory integration, and reward, such as the orbitofrontal cortex [t = 4.55, p = 0.003], the right temporal areas [t = 4.18, p = 0.002], the operculum and insula [t = 4.14, p = 0.005] only in individuals with a higher BMI. In addition, individuals with a higher BMI exhibit a specific reduced inhibition to food in the Go/No-Go task [p = 0.02, ε_p² = 0.02], which is associated with lower GM density in reward brain regions [orbital gyrus, t = 4.97, p = 0.005, and parietal operculum, t = 5.14, p < 0.001] and lower resting-state connectivity of the orbital gyrus to visual areas [fusiform gyrus, t = -4.64, p < 0.001 and bilateral occipital cortex, t = -4.51, p < 0.001 and t = -4.34, p < 0.001]. Therefore, a higher BMI is predictive of non food-specific slower visual subliminal processing, which is linked to morphological alterations of key areas involved in awareness, high-level sensory integration, and reward. At a late, conscious stage of visual processing a higher BMI is associated with a specific bias towards food and with lower GM density in reward brain regions. Finally, independently of BMI, volumetric variations and connectivity patterns in different brain regions are associated with variability in bCFS and Go/No-Go performances.

Expectancy to Eat Modulates Cognitive Control and Attention Toward Irrelevant Food and Non-food Images in Healthy Starving Individuals. A Behavioral Study

It is thought that just as hunger itself, the expectancy to eat impacts attention and cognitive control toward food stimuli, but this theory has not been extensively explored at a behavioral level. In order to study the effect of expectancy to eat on attentional and cognitive control mechanisms, 63 healthy fasting participants were presented with an affective priming spatial compatibility Simon task that included both food and object (non-food) distracters. The participants (N = 63) were randomly assigned to two groups: an "immediate expectancy" group made up of participants who expected to eat immediately after the task (N = 31; females = 21; age = 26.8 ± 9.6) and a "delayed expectancy" cohort made up of individuals who expected to eat a few hours later (N = 32; females = 21; age = 25.0 ± 8.0). Slower reaction times (RTs) toward the food and non-food distracters and a more pronounced effect on the RTs in the incompatible condition [i.e., the Simon effect (SE)] were noted in both groups. The effect of the food and non-food distracters on the RTs was more pronounced in the immediate with respect to the delayed expectancy group. The magnitude of the SE for the food and the non-food distracters was also greater in the immediate with respect to the delayed expectancy group. These results seem to indicate that when the expectancy to eat is short, the RTs are delayed, and the SE is more pronounced when food and non-food distracters are presented. Instead, when the expectancy to eat is more distant, the distracters have less of an effect on the RTs and the correspondence effect is smaller. Our results suggest that the expectancy to eat can modulate both attention orienting and cognitive control mechanisms in healthy fasting individuals when distracting details are competing with information processing during goal directed behavior.

ImpulsePal: The systematic development of a smartphone app to manage food temptations using intervention mapping

BACKGROUND

Impulsive processes driving eating behaviour can often undermine peoples' attempts to change their behaviour, lose weight and maintain weight loss.

AIM

To develop an impulse management intervention to support weight loss in adults.

METHODS

Intervention Mapping (IM) was used to systematically develop the "ImpulsePal" intervention. The development involved: (1) a needs assessment including a qualitative study, Patient and Public advisory group and expert group consultations, and a systematic review of impulse management techniques; (2) specification of performance objectives, determinants, and change objectives; (3) selection of intervention strategies (mapping of change techniques to the determinants of change); (4) creation of programme materials; (5) specification of adoption and implementation plans; (6) devising an evaluation plan.

RESULTS

Application of the IM Protocol resulted in a smartphone app that could support reductions in unhealthy (energy dense) food consumption, overeating, and alcoholic and sugary drink consumption. ImpulsePal includes inhibition training, mindfulness techniques, implementation intentions (if-then planning), visuospatial loading, use of physical activity for craving management, and context-specific reminders. An "Emergency Button" was also included to provide access to in-the-moment support when temptation is strong.

CONCLUSIONS

ImpulsePal is a novel, theory- and evidence-informed, person-centred app that aims to support impulse management for healthier eating. Intervention Mapping facilitated the incorporation of app components that are practical operationalisations of change techniques targeting our specific change objectives and their associated theoretical determinants. Using IM enabled transparency and provided a clear framework for evaluation, and enhances replicability and the potential of the intervention to accomplish the desired outcome of facilitating weight loss through dietary change.

Automatic attentional bias toward high-calorie food cues and body shape concerns in individuals with a high level of weight suppression: Preliminary findings

This study aimed to investigate differences in attentional processes in response to food cues and body shape concerns according to an individual's level of weight suppression. Among 470 women in their 20s, nonobese participants (body mass index [BMI] <25 kg/m²) were divided into two groups according to weight history. If the difference between their highest weight ever and current weight was greater than 10%, they were assigned to the high level of weight suppression (H-WS) group (n = 24); if it was less than 5%, they were assigned to the low level of weight suppression (L-WS) group (n = 29). Self-reported body shape concerns and bulimia nervosa symptoms were assessed. Visual attentional processes were recorded using an eye tracker while participants completed a free-viewing task composed of pairs of high- and low-calorie food cues. After controlling for current BMI, the H-WS group reported higher body shape concerns and higher levels of bulimia nervosa symptoms than did the L-WS group. In the free-viewing task, after controlling for current BMI, body shape concerns, and bulimia nervosa symptoms, the H-WS group had a significantly longer dwell time for high-calorie compared with low-calorie food cues than did the L-WS group, and this difference was observed for the first 1000 ms. Compared with individuals with low weight suppression, the vulnerability to bulimia nervosa symptoms observed in individuals with high weight suppression may be associated with a higher automatic approach tendency toward high-calorie foods after adjusting for body shape concerns.

Food Folio by Columbia Center for Eating Disorders: A Freely Available Food Image Database

Food images are useful stimuli for the study of cognitive processes as well as eating behavior. To enhance rigor and reproducibility in task-based research, it is advantageous to have stimulus sets that are publicly available and well characterized. Food Folio by Columbia Center for Eating Disorders is a publicly available set of 138 images of Western food items. The set was developed for the study of eating disorders, particularly for use in tasks that capture eating behavior characteristic of these illnesses. It contains foods that are typically eaten, as well as those typically avoided, by individuals with eating disorders. Each image has now been rated across 17 different attributes by a large general United States population sample via Amazon's Mechanical Turk (n = 1054). Ratings included subjective attributes (e.g., tastiness, healthiness, and favorable texture) as well as estimates of nutrient content (e.g., fat and carbohydrate). Each participant rated a subset of stimulus set food items (46 foods) on all 17 dimensions. Additional description of the image set is provided in terms of physical image information and accurate nutritional information. Correlations between subjective ratings were calculated and an exploratory factor analysis and exploratory cluster analysis completed. Outcomes of the factor analysis suggested foods may be described along three latent factors of healthiness, tastiness, and umami taste; the cluster analysis highlighted five distinct clusters of foods varying on these same dimensions. Descriptive outcomes indicated that the stimulus set includes a range of foods that vary along multiple dimensions and thus is likely to be useful in addressing various research questions surrounding eating behavior and cognition in healthy populations, as well as in those with eating disorders. The provision of comprehensive descriptive information allows for stimulus selection that is optimized for a given research question and promotes strong inference.

Unseen food images capture the attention of hungry viewers: Evidence from event-related potentials

Motivationally relevant visual targets appear to capture visuospatial attention. This capture is evident behaviorally as faster and more accurate responses, and neurally as an enhanced-amplitude of the N2pc - an index of spatial attention allocation, which is observed even when observers are unaware of the target. In the case of reinforcers such as food or substances of dependence, it is likely that the motivational state of craving accompanying deprivation potentiates this capture. The automaticity of such attentional capture by reward-associated stimuli, as well as its possible interaction with craving, is as yet not completely understood, though it is likely a major explanatory factor in motivated behaviors. For the present experiment, participants completed two EEG recording sessions: one just after eating lunch (sated/non-craving), and the other following a minimum 12-h period of fasting (hungry/craving). For both sessions, participants identified food- and clothing-related targets embedded in an object-substitution masking paradigm, which yielded trials of full target visibility, as well as trials for which targets were present but undetected. Although masking equally disrupted visual awareness of both classes of targets as measured behaviorally, a three-way hunger by visibility by target interaction was observed in the neural data, with unseen food targets eliciting an enhanced N2pc. Interestingly, this subliminal attentional capture by food-related items was observed only during the "hungry" session. No such capture was evident under conditions of full visibility. These findings indicate that attentional capture by food-related images, and reflected in enhancements of the N2pc, is spurred by hunger, and that this effect can be viewed as automatic, or independent of explicit awareness of food-relevant target content.

Exploring the Role of Self-Kindness in Making Healthier Eating Choices: A Preliminary Study

Background

Food selection is an important factor in the prevalence of obesity, and regularly choosing nutrient-poor high-energy foods can have negative health consequences. The present study tested whether the use of mindful construal diaries (MCD) combined with self-kindness could promote healthier eating choices.

Method

Ninety participants were randomly assigned to either a self-kindness to the mind condition or self-kindness to the mind and body condition, and were served M&Ms and grapes as an unhealthy and healthy option, respectively.

Results

The results suggested that a difference in consumption was found between the two conditions, with participants in the self-kindness to the mind condition consuming significantly more grapes than those in the self-kindness to the mind and body condition. However, this difference was restricted to those who are usually low consumers of fruit and vegetable.

Conclusion

The effect of self-kindness towards promoting heathier eating whilst considering the body thus appears to require further investigation. Limitations and recommendations for future research are discussed.

Learned value and predictiveness affect gaze but not figure assignment

Many factors affect figure-ground segregation, but the contributions of attention and reward history to this process is uncertain. We conducted two experiments to investigate whether reward learning influences figure assignment and whether this relationship was mediated by attention. Participants learned to associate certain shapes with a reward contingency: During a learning phase, they chose between two shapes on each trial, with subsets of shapes associated with high-probability win, low-probability win, high-probability loss, and low-probability loss. In a test phase, participants were given a figure-ground task, in which they indicated which of two regions that shared a contour they perceived as the figure (high-probability win and low-probability win shapes were pitted against each other, as were high-probability loss and low-probability loss shapes). The results revealed that participants had learned the reward contingencies and that, following learning, attention was reliably drawn to the optimal stimulus. Despite this, neither reward history nor the resulting attentional allocation influenced figure-ground organization.

Body Mass Index and stimulus control: Results from a real-world study of eating behaviour

BACKGROUND

Evidence suggests decisions about when, what, and how much to eat can be influenced by external (location, food outlet presence, food availability) and internal (affect) cues. Although the relationship between stimulus control and obesity is debated, it is suggested that individuals with higher BMIs are more driven by cues to eating than individuals in the healthy-weight range (HWR). This study investigates the influence of stimulus control on real-world food intake, and whether stimulus control differs by BMI. It was hypothesised that, compared to those in the HWR, eating among individuals with higher BMIs would be under greater stimulus control.

METHOD

74 participants (n = 34 BMI < 24.9, n = 40 BMI > 24.9) recorded food intake for 14 days using Ecological Momentary Assessment. Participants also responded to 4-5 randomly-timed assessments per day. Known external and internal eating cues were assessed during both assessment types. Within-person logistic regression analyses were used to predict eating vs. non-eating occasions from stimulus control domains.

FINDINGS

Results support the hypothesis that eating was influenced by stimulus control: food availability, affect, time of day, and location significantly distinguished between eating and non-eating instances (AUC-ROC = 0.56-0.69, all p's < 0.001). The presence of food outlets was significantly better at distinguishing between eating and non-eating instances for those with higher BMIs (compared to individuals in the HWR).

DISCUSSION

Results support the notion of stimulus control in shaping eating decisions. Differences in levels of stimulus control between participants in the HWR compared to those with a high BMI suggest that dietary improvement interventions may be more effective when they are tailored to the individual and consider environmental influences on eating behaviour.