Decision-Making Deficits and Overeating: A Risk Model for Obesity

Efficacy of a cognitive training based on inhibitory spillover and attribute conditioning: No weight and food intake reductions in adults with overweight and obesity

BACKGROUND

Overeating and obesity have been linked to deficient self-control and recent evidence suggests that the inhibitory spillover effect (ISE) may be an effective means to improve self-control. Specifically, it was shown that the ISE increases self-control by transfer of self-control capacity from one domain to another unrelated domain. Against this backdrop, our aim was to reduce hedonic food intake and body weight in non-dieting participants with overweight and obesity by transferring inhibitory control abilities from a food-unrelated domain to the food domain by means of an attribute conditioning procedure in a novel cognitive training (vs. a placebo training) comprising 8-sessions delivered over four weeks.

METHOD

In total, 93 adults with overweight and obesity were included in a two-arm randomized controlled trial and assigned to the computerized cognitive training or a placebo training (active control condition). Food intake in a bogus taste test and body weight were assessed prior to and after the training. Weight was additionally assessed at 3-months follow-up.

RESULTS

There was no improvement in food intake and weight reduction.

DISCUSSION

The cognitive training based on the ISE and attribute conditioning (ISAC) is not yet ready for application. Future studies need to identify the factors critical for a successful implementation of conditioning procedures aiming to associate food stimuli with self-control in overweight and obesity.

Healthy dietary choices involve prefrontal mechanisms associated with long-term reward maximization but not working memory

Taste and health are critical factors to be considered when choosing foods. Prioritizing healthiness over tastiness requires self-control. It has also been suggested that self-control is guided by cognitive control. We then hypothesized that neural mechanisms underlying healthy food choice are associated with both self-control and cognitive control. Human participants performed a food choice task and a working memory task during functional MRI scanning. Their degree of self-control was assessed behaviorally by the value discount of delayed monetary rewards in intertemporal choice. Prioritizing healthiness in food choice was associated with greater activity in the superior, dorsolateral, and medial prefrontal cortices. Importantly, the prefrontal activity was greater in individuals with smaller delay discounting (i.e. high self-control) who preferred a delayed larger reward to an immediate smaller reward in intertemporal choice. On the other hand, working memory activity did not show a correlation with delay discounting or food choice activity, which was further supported by supplementary results that analyzed data from the Human Connectome Project. Our results suggest that the prefrontal cortex plays a critical role in healthy food choice, which requires self-control, but not working memory, for maximization of reward attainments in a remote future.

Weight loss impacts risky decisions in obesity

BACKGROUND & AIMS

Risky decision making is shaped by individual psychological and metabolic state. Individuals with obesity show not only altered risk behavior, but also metabolic and psychological abnormalities. The aim of the present study was to investigate whether a substantial weight loss in individuals with severe obesity will 1) normalize their metabolic and psychological state and 2) will change their pattern of decision guidance.

METHODS

We assessed the effect of glycated hemoglobin (HbA1c) and mood on risk behavior in individuals with obesity (n = 62, 41 women; BMI, 46.5 ± 4.8 kg/m2; age, 44.9 ± 14.7 years) before and after 10-weeks weight loss intervention.

RESULTS

Results showed that this intervention reduced participants' risk behavior, which was significantly predicted by their changes in BMI. Before intervention, mood, but not HbA1c significantly predicted decisions. After the weight loss, mood no longer, but HbA1c significantly predicted decisions.

CONCLUSION

Our findings shed light on the psychological and metabolic mechanisms underlying altered risky decision making in severe obesity and can inform the development of strategies in the context of weight loss interventions.

Effectiveness of an Artificial Intelligence-Assisted App for Improving Eating Behaviors: Mixed Methods Evaluation

BACKGROUND

A plethora of weight management apps are available, but many individuals, especially those living with overweight and obesity, still struggle to achieve adequate weight loss. An emerging area in weight management is the support for one's self-regulation over momentary eating impulses.

OBJECTIVE

This study aims to examine the feasibility and effectiveness of a novel artificial intelligence-assisted weight management app in improving eating behaviors in a Southeast Asian cohort.

METHODS

A single-group pretest-posttest study was conducted. Participants completed the 1-week run-in period of a 12-week app-based weight management program called the Eating Trigger-Response Inhibition Program (eTRIP). This self-monitoring system was built upon 3 main components, namely, (1) chatbot-based check-ins on eating lapse triggers, (2) food-based computer vision image recognition (system built based on local food items), and (3) automated time-based nudges and meal stopwatch. At every mealtime, participants were prompted to take a picture of their food items, which were identified by a computer vision image recognition technology, thereby triggering a set of chatbot-initiated questions on eating triggers such as who the users were eating with. Paired 2-sided t tests were used to compare the differences in the psychobehavioral constructs before and after the 7-day program, including overeating habits, snacking habits, consideration of future consequences, self-regulation of eating behaviors, anxiety, depression, and physical activity. Qualitative feedback were analyzed by content analysis according to 4 steps, namely, decontextualization, recontextualization, categorization, and compilation.

RESULTS

The mean age, self-reported BMI, and waist circumference of the participants were 31.25 (SD 9.98) years, 28.86 (SD 7.02) kg/m2, and 92.60 (SD 18.24) cm, respectively. There were significant improvements in all the 7 psychobehavioral constructs, except for anxiety. After adjusting for multiple comparisons, statistically significant improvements were found for overeating habits (mean -0.32, SD 1.16; P<.001), snacking habits (mean -0.22, SD 1.12; P<.002), self-regulation of eating behavior (mean 0.08, SD 0.49; P=.007), depression (mean -0.12, SD 0.74; P=.007), and physical activity (mean 1288.60, SD 3055.20 metabolic equivalent task-min/day; P<.001). Forty-one participants reported skipping at least 1 meal (ie, breakfast, lunch, or dinner), summing to 578 (67.1%) of the 862 meals skipped. Of the 230 participants, 80 (34.8%) provided textual feedback that indicated satisfactory user experience with eTRIP. Four themes emerged, namely, (1) becoming more mindful of self-monitoring, (2) personalized reminders with prompts and chatbot, (3) food logging with image recognition, and (4) engaging with a simple, easy, and appealing user interface. The attrition rate was 8.4% (21/251).

CONCLUSIONS

eTRIP is a feasible and effective weight management program to be tested in a larger population for its effectiveness and sustainability as a personalized weight management program for people with overweight and obesity.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04833803; https://classic.clinicaltrials.gov/ct2/show/NCT04833803.

Applying psycho-behavioural phenotyping in obesity characterization

Individual differences in obesity, beyond being explained by metabolic and medical complications, are understood by alterations in eating behaviour which underlie psychological processes. From this psychological perspective, studies have identified several potential characteristic features at the psycho-behavioural level that could additionally explain the maintenance of chronic excess weight or the unsuccessful results of current treatments. To date, despite the growing evidence, the heterogeneity of the psychological evidence associated with obesity has made it challenging to generate consensus on whether these psycho-behavioural phenotypes can be a complement to improve outcomes of existing interventions. For this reason, this narrative review is an overview focused on summarizing studies describing the psycho-behavioural phenotypes associated with obesity. Based on the literature, three psychological constructs have emerged: reward dependence, cognitive control, and mood and emotion. We discuss the clinical implications of stratifying and identifying these psycho-behavioural profiles as potential target for interventions which may ensure a better response to treatment in individuals with obesity. Our conclusions pointed out a considerable overlap between these psycho-behavioural phenotypes suggesting bidirectional interactions between them. These findings endorse the complexity of the psycho-behavioural features associated with obesity and reinforce the need to consider them in order to improve treatment outcomes.

Child-reported vegetable neophobia is associated with risk avoidance for distaste in children aged 4-15 years

Children who are food neophobic and/or picky eaters often refuse intake of especially fruits and vegetables, thereby narrowing their dietary variety and impairing the quality of their food intake. In this preregistered study, we investigated whether picky eating and food neophobia are related to bitter taste sensitivity (PROP taster status) and risk avoidance for distaste. A total of 367 children (201 girls; M age = 8.7 years, range: 4-15 years) participated in the study. They completed the vegetable neophobia subscale of the fruit and vegetable neophobia instrument (FVNI). A caregiver completed the child food rejection scale (CFRS), a parent-report measure of food neophobia and picky eating. Children's bitter taste sensitivity was measured with a PROP (6-n-propylthiouracil) taste strip, and the children completed a modified Children's Gambling Task (Candy Gambling Game) to measure risk avoidance for distaste. In this task, children could select cards from a risky deck (chance of winning two tasty cherry-flavoured jelly beans, but also the risk of getting a distasteful soap-flavoured jelly bean) or a safe deck (chance of winning one tasty jelly bean or no jelly bean). The results show that picky eating and food neophobia (either parent- or self-reported) are not related to PROP taster status. However, children who self-reported higher levels of vegetable neophobia showed less risky choice behaviour in the Candy Gambling Game, although this relationship was not found with parent-reported food neophobia. We conclude that risk avoidance for distaste, but not taste function, is associated with children's self-reported food rejection tendencies. To broaden the food repertoire of children high in food neophobia, it might be useful to reduce the perceived risk of distaste, when introducing a novel food or meal.

A Diet Pattern Characterized by Sugar-Sweetened Beverages Is Associated with Lower Decision-Making Performance in the Iowa Gambling Task, Elevated Stress Exposure, and Altered Autonomic Nervous System Reactivity in Men and Women

The executive brain mediates and facilitates a set of cognitive functions, such as decision making, planning, self-regulation, emotional regulation, and attention. Executive dysfunction and related diseases are a rising public health concern. Evidence supports a link between nutritional factors and executive function (EF), but relatively little information exists about the relationship between diet patterns and this higher order cognitive ability. We and others have reported on the relationships between body weight regulation and affective decision making, as measured by performance in the Iowa Gambling Task (IGT). However, little is known about the relationships between performance in this decision-making task and whole diet patterns. In this study, we tested whether data-derived diet patterns based on energy-adjusted food intake data from the Block Food Frequency Questionnaire were associated with decision-making performance in the IGT. Secondarily, we examined the influence of these diet patterns on self-reported chronic stress exposure and heart rate variability, which is a marker of autonomic nervous system (ANS) activity. In prior studies, stress and ANS activity were shown to influence decision-making performance in the IGT. In this study, five distinct diet patterns were identified by cluster and factor analyses. A diet pattern best characterized by elevated sugar-sweetened beverage and added sugar consumption was associated with the lowest decision-making performance (p = 0.0049) and higher stress exposure (p = 0.0097). This same diet pattern was associated (p = 0.0374) with an IGT-affiliated decline in high-frequency HRV and an increase in low-frequency HRV, suggesting diet-induced ANS regulatory shifts in response to performing the EF task. Compared to the sugar-sweetened beverage diet pattern, diet patterns defined by more fruits/vegetables and low red meat (p = 0.0048) or higher omega-3 fatty acids and seafood (p = 0.0029) consumption were associated with lower chronic stress exposure. All outcomes were statistically adjusted for differences in BMI, age, sex, education level, and sensorimotor ability. Our findings provide new information that further supports the potential importance of whole diet patterns on cognitive disease prevention.

Cognitive and clinical gender‐related differences among binge‐spectrum eating disorders: Analysis of therapy response predictors

OBJECTIVE

This study assessed gender-related differences in executive functions (decision-making, inhibitory control and cognitive flexibility), personality traits and psychopathological symptoms in binge-spectrum eating disorders (EDs). Secondly, we aimed to separately explore the predictive value of gender and executive functions in treatment outcome.

METHOD

A battery of self-reported and neurocognitive measures were answered by a sample of 85 patients (64 females) diagnosed with a binge-spectrum ED (41 BN; 44 binge eating disorder).

RESULTS

Data showed gender-related differences in executive functioning, displaying women lower inhibitory control and lower cognitive flexibility than men. Regarding personality traits and psychopathology symptoms, women presented higher reward dependence and cooperativeness, as well as more drive for thinness, body dissatisfaction, bulimia, and somatisation symptoms than men. Finally, worse executive functioning, particularly having lower ability in concept formation seems to predict worse treatment outcomes and dropout in these patients.

CONCLUSIONS

We described gender specific neuropsychological, personality and psychopathological impairments in patients with binge-spectrum EDs. Moreover, difficulties in executive functioning might have an impact on treatment response, since patients with a lower ability in concept formation are less likely to benefit from treatment. The present results can help improving current treatment approaches by tackling gender and individual differences.

Choices of (in)action in obesity: Implications for research on treatment and prevention

The obesity epidemic has crossed social-demographic barriers and is a matter of significant concern. Why do individuals fail to restrain from eating high-calorie foods and fail to follow treatment routines that reduce the risk of health complications? These questions have been addressed through behavioral and brain imaging studies on prefrontal cortex inhibitory mechanisms. Failure to inhibit undesirable behaviors has become a hallmark of obesity. In many life situations, obesity risk is increased by inaction (e.g., not taking blood pressure medication, not following a healthy diet). Risk by inaction has been defined as passive risk-taking, and it is correlated with traits such as procrastination, future time perspective, and cognitive avoidance. To the present, passive tendencies, specifically in the context of risk-taking behaviors, have not been addressed in the obesity literature. We introduce a framework in which active and passive risk-taking behaviors are integrated within the scope of bidirectional models of obesity that describe the brain as both the cause and the consequence of obesity vulnerability. The present perspective aims to foster new research on treatment and prevention, and also on the neurobiology of passive behaviors in obesity and other metabolic conditions.

A review of effort-based decision-making in eating and weight disorders

Effort-based decision-making provides a framework to understand the mental computations estimating the amount of work ("effort") required to obtain a reward. The aim of the current review is to systematically synthesize the available literature on effort-based decision-making across the spectrum of eating and weight disorders. More specifically, the current review summarises the literature examining whether 1) individuals with eating disorders and overweight/obesity are willing to expend more effort for rewards compared to healthy controls, 2) if particular components of effort-based decision-making (i.e. risk, discounting) relate to specific binge eating conditions, and 3) how individual differences in effort and reward -processing measures relate to eating pathology and treatment measures. A total of 96 studies were included in our review, following PRISMA guidelines. The review suggests that individuals with binge eating behaviours 1) are more likely to expend greater effort for food rewards, but not monetary rewards, 2) demonstrate greater decision-making impairments under risk and uncertainty, 3) prefer sooner rather than delayed rewards for both food and money, and 4) demonstrate increased implicit 'wanting' for high fat sweet foods. Finally, individual differences in effort and reward -processing measures relating to eating pathology and treatment measures are also discussed.

Exploring Potential Mediation Pathways on the Relationship Between Acculturation and Body Mass Index (BMI) Among Latino Adolescents

BACKGROUND

Positive associations have been observed between acculturation and body mass index (BMI), but the mediators of this relationship are not well established. Acculturation researchers have called for investigating the influence of socio-contextual variables as mediators. The objective of this study was to test the mediating effects of salty snacks, sweet snacks, physical activity, and sedentary behavior on the relationship between acculturation and BMI among Latino adolescents.

METHODS

Adolescents who self-identified as Latino (n = 431) at public high schools in Southern California were recruited and completed a self-report survey. A bootstrapped multiple mediation model was used to test mediation pathways.

RESULTS

Acculturation was positively associated with physical activity (B = 0.09, p < .05). The indirect effects of salty snacks, sweet snacks, physical activity, and sedentary behavior were not associated with BMI, suggesting no mediation.

CONCLUSIONS

Future research should examine additional mediating variables on the relationship between acculturation and BMI.

Identifying behavioral types of dietary lapse from a mobile weight loss program: Preliminary investigation from a secondary data analysis

Success in behavioral weight loss (BWL) programs depends on adherence to the recommended diet to reduce caloric intake. Dietary lapses (i.e., deviations from the BWL diet) occur frequently and can adversely affect weight loss outcomes. Research indicates that lapse behavior is heterogenous; there are many eating behaviors that could constitute a dietary lapse, but they are rarely studied as distinct contributors to weight outcomes. This secondary analysis aims to evaluate six behavioral lapse types during a 10-week mobile BWL program (eating a large portion, eating when not intended, eating an off-plan food, planned lapse, being unaware of caloric content, and endorsing multiple types of lapse). Associations between weekly behavioral lapse type frequency and weekly weight loss were investigated, and predictive contextual characteristics (psychological, behavioral, and environmental triggers for lapse) and individual difference (e.g., age, gender) factors were examined across lapse types. Participants (N = 121) with overweight/obesity (M_BMI = 34.51; 84.3% female; 69.4% White) used a mobile BWL program for 10 weeks, self-weighed weekly using Bluetooth scales, completed daily ecological momentary assessment of lapse behavior and contextual characteristics, and completed a baseline demographics questionnaire. Linear mixed models revealed significant negative associations between unplanned lapses and percent weight loss. Unplanned lapses from eating a large portion, eating when not intended, and having multiple "types" were significantly negatively associated with weekly percent weight loss. A lasso regression showed that behavioral lapse types share many similar stable factors, with other factors being unique to specific lapse types. Results add to the prior literature on lapses and weight loss in BWL and provide preliminary evidence that behavioral lapse types could aid in understanding adherence behavior and developing precision medicine tools to improve dietary adherence.

The COVID‐19 Pandemic and Consumption of Food away from Home: Evidence from High‐frequency Restaurant Transaction Data

This article investigates how the COVID‐19 pandemic and related public health measures affected the consumption of food away from home (FAFH) among Chinese consumers. We obtained access to the complete sales records from a major restaurant chain in China, for 111 sites located in 12 cities, covering over 5.6 million high‐frequency dining transactions made between 1 January 2019 and 31 December 2020. By applying a high‐dimensional fixed‐effects model, we found that, on average, consumers spent more and ordered more calories (as well as carbohydrates, protein, fat, and sodium) after the COVID‐19 outbreak than in the pre‐COVID‐19 period. Our results do not support the hypothesis that COVID‐19 led to healthier eating behaviors during and after the pandemic. Our results underline the importance of nutrition education and awareness programs to mitigate unhealthy eating habits generated by the pandemic and of the continued role of FAFH after the pandemic.

Relationship between BMI and alcohol consumption levels in decision making

BACKGROUND

Decision-making deficits in obesity and alcohol use disorder (AUD) may contribute to the choice of immediate rewards despite their long-term deleterious consequences.

METHODS

Gambling task functional MRI in Human connectome project (HCP) dataset was used to investigate neural activation differences associated with reward or punishment (a key component of decision-making behavior) in 418 individuals with obesity (high BMI) and without obesity (lean BMI) and either at high (HR) or low (LR) risk of AUD based on their alcohol drinking levels.

RESULTS

Interaction between BMI and alcohol drinking was seen in regions of the default mode network (DMN) and those implicated in self-related processing, memory, and salience attribution. ObesityHR relative to obesityLR also recruited DMN along with primary motor and regions implicated in inattention, negative perception, and uncertain choices, which might facilitate impulsive choices in obesityHR. Furthermore, obesityHR compared to leanHR/leanLR also demonstrated heightened activation in DMN and regions implicated in uncertain decisions.

CONCLUSIONS

These results suggest that BMI is an independent variable from that of alcohol drinking levels in neural processing of gambling tasks. Moreover, leanLR relative to leanHR, showed increased activation in motor regions [precentral and superior frontal gyrus] suggestive of worse executive function from excessive alcohol use. Delayed discounting measures failed to distinguish between obesity and high alcohol drinking levels, which as for gambling task results suggests independent negative effects of obesity and chronic alcohol drinking on decision-making. These findings highlight distinct associations of obesity and high-risk alcohol drinking with two key constituents of decision-making behavior.

The Co-occurrence of Pediatric Obesity and ADHD: an Understanding of Shared Pathophysiology and Implications for Collaborative Management

PURPOSE OF REVIEW

To describe what is known about the association between obesity and attention-deficit hyperactivity disorder (ADHD) in children along with the co-occurring conditions of sleep dysfunction, loss of control/binge eating disorder (LOC-ED/BED), and anxiety.

RECENT FINDINGS

Obesity and ADHD share common brain pathways (hypothalamic, executive, and reward centers) with pathophysiology in these areas manifesting in partial or complete expression of these diseases. Sleep dysfunction, LOC-ED/BED, and anxiety share similar pathways and are associated with this disease dyad. The association of obesity and ADHD with sleep dysfunction, LOC-ED/BED, and anxiety is discussed. An algorithm outlining decision pathways for patients with obesity and with and without ADHD is presented. Future research exploring the complex pathophysiology of both obesity and ADHD as well as co-occurring conditions is needed to develop clinical guidelines and ultimately assist in providing the best evidence-based care.

Hierarchical integrated processing of reward-related regions in obese males: A graph-theoretical-based study

Abnormal activities in reward-related regions are associated with overeating or obesity. Preliminary studies have shown that changes in neural activity in obesity include not only regional reward regions abnormalities but also impairments in the communication between reward-related regions and multiple functional areas. A recent study has shown that the transitions between different neural networks are nonrandom and hierarchical, and that activation of particular brain networks is more likely to occur after other brain networks. The aims of this study were to investigate the key nodes of reward-related regions in obese males and explore the hierarchical integrated processing of key nodes. Twenty-four obese males and 24 normal-weight male controls of similar ages were recruited. The fMRI data were acquired using 3.0 T MRI. The fMRI data preprocessing was performed in DPABI and SPM 12. Degree centrality analyses were conducted using GRETNA toolkit, and Granger causality analyses were calculated using DynamicBC toolbox. Decreased degree centrality was observed in left ventral medial prefrontal cortex (vmPFC) and right parahippocampal/hippocampal gyrus in group with obesity. The group with obesity demonstrated increased effective connectivity between left vmPFC and several regions (left inferior temporal gyrus, left supplementary motor area, right insular cortex, right postcentral gyrus, right paracentral lobule and bilateral fusiform gyrus). Increased effective connectivity was observed between right parahippocampal/hippocampal gyrus and left precentral/postcentral gyrus. Decreased effective connectivity was found between right parahippocampal/hippocampal gyrus and left inferior parietal lobule. This study identified the features of hierarchical interactions between the key reward nodes and multiple function networks. These findings may provide more evidence for the existing view of hierarchical organization in reward processing.

Adiposity covaries with signatures of asymmetric feedback learning during adaptive decisions

Unhealthy weight gain relates, in part, to how people make decisions based on prior experience. Here we conducted post hoc analysis on an archival data set to evaluate whether individual differences in adiposity, an anthropometric construct encompassing a spectrum of body types, from lean to obese, associate with signatures of asymmetric feedback learning during value-based decision-making. In a sample of neurologically healthy adults (N = 433), ventral striatal responses to rewards, measured using fMRI, were not directly associated with adiposity, but rather moderated its relationship with feedback-driven learning in the Iowa gambling task, tested outside the scanner. Using a biologically inspired model of basal ganglia-dependent decision processes, we found this moderating effect of reward reactivity to be explained by an asymmetrical use of feedback to drive learning; that is, with more plasticity for gains than for losses, stronger reward reactivity leads to decisions that minimize exploration for maximizing long-term outcomes. Follow-up analysis confirmed that individual differences in adiposity correlated with signatures of asymmetric use of feedback cues during learning, suggesting that reward reactivity may especially relate to adiposity, and possibly obesity risk, when gains impact future decisions more than losses.

Is Dietary Nonadherence Unique to Obesity and Weight Loss? Results From a Randomized Clinical Trial

OBJECTIVE

Weight stigma is associated with poor dietary adherence, yet adherence is essential for weight loss and maintenance. This study aimed to determine differences in dietary adherence and perceived hunger between lean individuals and two groups of individuals with obesity.

METHODS

In a 6-week outpatient dietary intervention (23 males; aged 48  [SD 14] years), lean participants (n = 23; BMI 23  [SD 2] kg/m² ) received a weight-maintaining energy needs (WMEN) diet, and participants with obesity (BMI 36  [SD 7]) were randomized to either WMEN (n = 18) or a 35% calorie-reduced (CR) diet (n = 19). All food was provided, and multiple adherence and hunger ratings were assessed daily and weekly on an outpatient basis and in person at twice-weekly visits (e.g., 24-hour recall, diaries).

RESULTS

Weight decreased more in the group of CR individuals with obesity (β = -0.301 kg/wk, P = 0.02) compared with the group of lean individuals and the group of WMEN individuals with obesity. However, total percent adherence did not differ between groups (P = 0.60), and hunger scores did not change across groups over time (P = 0.08).

CONCLUSIONS

Results indicate that there are no differences in dietary adherence between lean individuals and individuals with obesity and adherence is not associated with adiposity or hunger. Thus, the belief that nonadherence (e.g., lack of willpower) is unique to obesity is untrue and may perpetuate weight bias and stigma.

Promoting self-control in overweight and obese children

Introduction

Background and objective: impulsiveness might affect the ability of an individual to plan meals, eat regularly, and resist impulses to enjoy foods that are high in fat and sugars in a particular way. The objective of the present study was to evaluate the effectiveness of a fading strategy regarding a reinforcer dimension to promote the development of self-control and decrease impulsive choice among 14 overweight and obese children. Material and methods: to meet this objective, an experimental procedure of choice behavior was used to evaluate the impulsivity and self-control choices influenced by four reinforcer dimensions on a computer: reinforcement rate, reinforcer quality, immediacy of the reinforcement, and response effort. Results: the results indicate that the children's decisions were influenced primarily by the immediacy of the reinforcement and the reinforcement rate; therefore, the children's behavior can be classified as impulsive. Based on these results, a fading procedure was implemented for self-control training in which the immediacy values of the reinforcement and other influential dimensions that devalued the reinforcer were progressively increased. Conclusions: after this fading strategy, a change in preference was observed among the children with regard to the proportion of alternative responses that produced high rates of reinforcement or were of higher quality compared with the allocation of choices associated with immediate reinforcement, which required less effort and were of lower quality. It is possible to design strategies regarding the development of self-control based on the contrasting qualities of these dimensions and the gradual training of tolerance of restrictions on access to the reinforcer.

Sucrose intake lowers μ-opioid and dopamine D2/3 receptor availability in porcine brain

Excessive sucrose consumption elicits addiction-like craving that may underpin the obesity epidemic. Opioids and dopamine mediate the rewarding effects of drugs of abuse, and of natural rewards from stimuli such as palatable food. We investigated the effects of sucrose using PET imaging with [¹¹C]carfentanil (μ-opioid receptor agonist) and [¹¹C]raclopride (dopamine D2/3 receptor antagonist) in seven female anesthetized Göttingen minipigs. We then gave minipigs access to sucrose solution for one hour on 12 consecutive days and performed imaging again 24 hours after the final sucrose access. In a smaller sample of five minipigs, we performed an additional [¹¹C]carfentanil PET session after the first sucrose exposure. We calculated voxel-wise binding potentials (BP_ND) using the cerebellum as a region of non-displaceable binding, analyzed differences with statistical non-parametric mapping, and performed a regional analysis. After 12 days of sucrose access, BP_ND of both tracers had declined significantly in striatum, nucleus accumbens, thalamus, amygdala, cingulate cortex and prefrontal cortex, consistent with down-regulation of receptor densities. After a single exposure to sucrose, we found decreased binding of [¹¹C]carfentanil in nucleus accumbens and cingulate cortex, consistent with opioid release. The lower availability of opioid and dopamine receptors may explain the addictive potential associated with intake of sucrose.

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.

Food craving predicts the consumption of highly palatable food but not bland food

The impact of obesity on physical and psychological health is well recognized in the literature with, among others, evidence of alterations in cognition. Indeed, obese populations are characterized by lower executive functions as well as an enhanced food craving. However, the relationship between executive functions and food craving remains unexplored. Moreover, these two variables have also been shown to predict food intake, but studies in the context of obesity are lacking. Thus, this study had two objectives: (1) determining if executive functions and food craving are linked, and (2) examining the predictors of highly palatable food intake and bland food intake. First, it was hypothesized that executive functions would be negatively associated with food craving. Second, it was expected that food craving would predict positively highly palatable food intake but not bland food intake. Third, it was predicted that executive functions would predict negatively highly palatable food intake and positively bland food intake. 48 participants (34 females) with BMIs ranging from 17.9 to 46.4 took part in two experimental sessions. First, executive functions were assessed using the delayed discounting task (impulsivity towards food and money) and the color-word interference test (CWIT; inhibition/flexibility). Second, a cue-induced food craving protocol, with images as well as real food, was administered followed by an ad libitum food intake protocol including both highly palatable and bland food. The inhibition/flexibility condition of the CWIT was significantly and negatively correlated with food craving following induction. Highly palatable food intake was significantly predicted by food craving following induction, but bland food intake was not. This study reveals an association between lower inhibition/flexibility and susceptibility to food craving induction that is of great importance in obesogenic environments. Moreover, this study confirmed the link between food craving and food intake, and showed for the first time a specific contribution of food craving to highly palatable food intake but not to bland food intake, highlighting its potential influence in obesity. This work leads to future research questions regarding the possible benefits of cognitive remediation interventions, as well as interventions aiming at reducing food craving, in weight loss programs. LEVEL OF EVIDENCE: Level IV, quasi-experimental study.

The Motivational Aspect of Children's Delayed Gratification: Values and Decision Making in Middle Childhood

Delayed gratification is the ability to postpone an immediate gain in favor of greater and later reward. Although delayed gratification has been studied extensively, little is known about the motivation behind children's decisions. Since values are cognitive representations of individuals' motivations, which serve to guide behavior, we studied the relationship between children's values and delayed gratification. Two main distinct motivations overlapping with values may underlie this decision: conservation - the desire to reduce uncertainty and preserve the status quo, and self-enhancement - the desire to maximize resources and profit for the self. Accordingly, we hypothesized that conservation values would relate to children's preference to hold on to what is given as soon as possible, and that self-enhancement values would relate to children's preference for delaying gratification. Seven-year old children (N = 205) ranked their values with the Picture-Based Values Survey (Döring et al., 2010) as part of the Longitudinal Israeli Study of Twins (LIST) (Avinun and Knafo, 2013). The children also played a decision-making animation game that included delayed gratification decisions. In support of our hypotheses, greater delayed gratification related negatively to conservation values, specifically to security and tradition, and related positively to self-enhancement values, especially power and achievement. This is one of the first demonstrations that children's values relate meaningfully to their behaviors.

Altered monetary loss processing and reinforcement-based learning in individuals with obesity

Individuals with obesity are often characterized by alterations in reward processing. This may affect how new information is used to update stimulus values during reinforcement-based learning. Here, we investigated obesity-related changes in non-food reinforcement processing, their impact on learning performance as well as the neural underpinnings of reinforcement-based learning in obesity. Nineteen individuals with obesity (BMI > = 30 kg/m², 10 female) and 23 lean control participants (BMI 18.5–24.9 kg/m², 11 female) performed a probabilistic learning task during functional magnetic resonance imaging (fMRI), in which they learned to choose between advantageous and disadvantageous choice options in separate monetary gain, loss, and neutral conditions. During learning individuals with obesity made a significantly lower number of correct choices and accumulated a significantly lower overall monetary outcome than lean control participants. FMRI analyses revealed aberrant medial prefrontal cortex responses to monetary losses in individuals with obesity. There were no significant group differences in the regional representation of prediction errors. However, we found evidence for increased functional connectivity between the ventral striatum and insula in individuals with obesity. The present results suggest that obesity is associated with aberrant value representations for monetary losses, alterations in functional connectivity during the processing of learning outcomes, as well as a decresased reinforcement-based learning performance. This may affect how new information is incorporated to adjust dysfunctional behavior and could be a factor contributing to the maintenance of dysfunctional eating behavior in obesity.

Eating Pleasure in a Sample of Obese Brazilian Women: A Qualitative Report of an Interdisciplinary Intervention Based on the Health at Every Size Approach

INTRODUCTION

Health at Every Size (HAES) is a weight-neutral approach focused on promoting healthy behaviors in people with different body sizes and on enhancing pleasure derived from consuming food to achieve sustainable healthy eating outcomes. However, to the best of our knowledge, there are no studies in the literature assessing the effects of the HAES approach on perceptions of eating pleasure.

OBJECTIVE

We qualitatively investigated the perceptions of obese women about eating pleasure before and after a new interdisciplinary, nonprescriptive intervention based on the HAES approach.

DESIGN

The intervention was a randomized controlled clinical trial, designated as Health and Wellness in Obesity, conducted over 7 months at University of São Paulo (Brazil). We used a qualitative approach to data construction and analysis of perceptions about eating pleasure. Participants were randomized to either the intervention (I-HAES) group or the control (CTRL) group. The I-HAES group featured individual nutritional counseling, group practice of enjoyable physical activity, and philosophical workshops. The CTRL group was a traditional HAES intervention group (lecture-based model). Focus group discussions eliciting perceptions of pleasure around eating were conducted at baseline and post-study. Focus group transcripts were analyzed by exploratory content analysis.

PARTICIPANTS

Forty-three women aged 25 to 50 years with body mass index (measured in kilograms per square meter) between 30 and 39. 9 completed the intervention and the focus groups, with 32 in the I-HAES group and 11 in the CTRL group.

RESULTS

Lack of guilt about experiencing pleasure while eating and increased reflection on their own desires increased in participants of both groups after the study. The I-HAES group also displayed a greater sense of autonomy related to eating, increased pleasure in commensality, familiarity with the practice of cooking, and decreased automatic eating.

CONCLUSION

HAES-based intervention featuring nutritional counseling, appreciation for physical activity, and philosophical engagement was shown to stimulate pleasure around eating without leading to indiscriminate eating.

Attentional Bias, "Cool" and "Hot" Executive Functions in Obese Patients: Roles of Body Mass Index, Binge Eating, and Eating Style

PURPOSE/BACKGROUND

Obesity is recognized as an important risk factor for many chronic diseases and is a major health issue. The current study examined attentional bias to food and the "cool" (inhibitory control and mental flexibility) and "hot" (affective decision making) executive functions (EFs) in obese patients preparing for bariatric surgery. In addition to body mass index (BMI), this study examined the impact of the binge-eating tendency and eating styles.

METHODS

The study population comprised 21 morbidly obese patients preparing to undergo bariatric surgery (BMI ≥30 kg/m) and 21 normal-weight controls (24 kg/m > BMI ≥ 18.5 kg/m). The Visual Probe Task was adopted to examine attentional bias toward food-related cues. The Stop-Signal Task and the Color Trails Test were used to assess inhibitory control and mental flexibility, respectively. The Iowa Gambling Task was administered to assess the affective decision making.

RESULTS

(1) The obese patients showed poorer performances on cool EFs (for Color Trails Test, P = 0.016, ηp = 0.136; for Stop-Signal Task, P = 0.049, ηp = 0.093) and hot EF (for Iowa Gambling Task, normal controls showed progressed performance, P = 0.012, ηp = 0.077, but obese patients did not show this progress, P = 0.111, ηp = 0.089) compared with the normal controls; (2) participants with low binge-eating tendency had larger attentional biases at 2000 milliseconds than at 200 milliseconds on food-related cues (P = 0.003, ηp = 0.363); and (3) low-restrained participants exhibited attentional bias toward the low-calorie food cues, compared with the high-restrained group (P = 0.009, ηp = 0.158).

CONCLUSIONS

The current study contributes to the development of a different therapeutic focus on obese patients and binge eaters.

Inhibitory control mediates a negative relationship between body mass index and intelligence: A neurocognitive investigation

The structure and function of the human brain is closely related to cognitive processes of the mind and physiological processes of the body, suggesting that an intricate relationship exists between cognitive health, body health, and underlying neural architecture. In the current study, morphometric differences in cortical and subcortical gray matter regions, white matter integrity, and resting-state functional connectivity was assessed to determine what combinations of neural variables best explain an interconnected behavioral relationship between body mass index (BMI), general intelligence, and specific measures of executive function. Data for 82 subjects were obtained from the Nathan Kline Institute Rockland Sample. Behavioral results indicated a negative relationship between BMI and intelligence, which exhibited mediation by an inhibitory measure of executive function. Neural analyses further revealed generally contrasting associations of BMI, intelligence, and executive function with cortical morphometric regions important for inhibitory control and directed attention. Moreover, BMI related to morphometric alterations in components of a frontolimbic network, namely reduced thickness in the anterior cingulate cortex and ventromedial prefrontal cortex, whereas intelligence and inhibitory control primarily related to increased thickness and volume in parietal regions, as well as significantly increased across-network connectivity of visual and default mode resting-state networks. These results propose that medial prefrontal structure and interconnected frontolimbic and frontoparietal networks are important to consider in the relationship between BMI, intelligence, and executive function.

To What Extent Memory Could Contribute to Impaired Food Valuation and Choices in Obesity?

Obesity is associated with a diverse array of cognitive and affective deficits, among which impairments in food valuation and choices have received increasing attention. The neural underpinnings of such impairments, however, remain poorly understood, partly because a complete understanding of these processes under normal conditions has yet to be achieved. A rapidly growing literature on the interaction between memory and decision-making has begun to highlight the integral role of memory in decision making especially in the real world, as well as the role of the hippocampus in supporting flexible decision making. Perhaps not coincidentally, altered memory performances in obesity have been well documented, and the underlying neurobiological bases of these memory alterations have also started to be better described, involving pathologies at the biochemical, cellular, and circuit levels. Despite such correspondence, the link between memory impairments and food valuation/choice deficits in obesity has received little attention. In this article, we first summarize the growing empirical support for the relevance of memory for decision making, focusing on flexible value-based decisions. We then describe converging evidence on different forms of memory impairments accompanying obesity. Building on these findings, we formulate a general neuropsychological framework and discuss how dysfunctions in the formation and retrieval of memory may interfere with adaptive decision making for food. Finally, we stress the important practical implications of this framework, arguing that memory deficits are likely a significant contributor to suboptimal food purchase and eating behavior exhibited by obese individuals.

Is ventromedial prefrontal cortex critical for behavior change without external reinforcement?

Cue-approach training (CAT) is a novel paradigm that has been shown to induce preference changes towards items without external reinforcements. In the task, the mere association of a neutral cue and a speeded button response has been shown to induce a behavioral choice preference change lasting for months. This paradigm includes several phases: after the training of individual items, behavior change is manifested in binary choices of items with similar initial values. Neuroimaging data have implicated the ventromedial prefrontal cortex (vmPFC) in the choice phase of this task. However, the neural mechanisms underlying the preference changes induced by training remain unclear. Here, we asked whether the ventromedial frontal lobe (VMF) is critical for the non-reinforced preference change induced by CAT. For this purpose, 11 participants with focal lesions involving the VMF and 30 healthy age-matched controls performed the CAT. The VMF group was similar to the healthy age-matched control group in the ranking and training phases. As a group, the healthy age-matched controls exhibited a training-induced behavior change, while the VMF group did not. However, on an individual level analysis we found that some of the VMF participants showed a significant preference shift. Thus, we find mixed evidence for the role of VMF in this paradigm. This is another step towards defining the mechanisms underlying the novel form of behavioral change that occurs with CAT.

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We tested participants with focal lesions involving ventromedial frontal lobe (VMF).

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Participants performed a behavioral change task without external reinforcements.

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The VMF group did not exhibit behavior change but some individuals in it did.

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We find mixed evidence for the role of VMF in this paradigm.

A multimodal investigation of impulsivity as a moderator of the relation between momentary elevations in negative internal states and subsequent dietary lapses

Suboptimal outcomes from behavioral weight loss (BWL) treatments are partially attributable to accumulated instances of non-adherence to dietary prescriptions (i.e., dietary lapses). Results identifying negative internal triggers for dietary lapses are inconsistent, potentially due to individual differences that impact how individuals respond to cues. Impulsivity is one factor that likely influences reactivity to internal states. We examined three dimensions of impulsivity (delay discounting, inhibitory control, and negative urgency) as moderators of the relation between affective and physical states and subsequent dietary lapses at the beginning of BWL. Overweight/obese adults (n = 189) completed behavioral and self-reported measures of impulsivity at baseline of BWL and an ecological momentary assessment (EMA) protocol across the first two weeks of treatment to report on affective/physical states and instances of dietary lapses. Results indicated that baseline negative urgency, but not delay discounting or inhibitory control, was positively associated with overall lapse risk. Moderation analyses indicated that poorer inhibitory control strengthened the relation between momentary increases in stress and subsequent dietary lapse, and higher negative urgency strengthened the relation between increases in loneliness and dietary lapse. Negative urgency also moderated the impact of momentary hunger on subsequent dietary lapse risk in an unexpected direction, such that higher negative urgency weakened the relation between hunger and subsequent lapse. Results lend partial and tentative support for the moderating role of impulsivity on the relation between internal states and lapse likelihood. With replication, the development and testing of personalized treatment components based on baseline impulsivity level may be warranted.

Body mass and wages: New evidence from quantile estimation

I estimate the effect of body mass index (BMI) on wages across the unconditional distribution of wages. I find that for whites and Hispanics the effect of BMI is generally decreasing across the wage distribution; at the .9 quantile of the wage distribution, a two standard deviation increase in BMI reduces wages by 8% for white males, 13% for white females, 9% for Hispanic males, and 16% for Hispanic females. Conversely, at the .1 quantile, a two standard deviation increase in BMI affects wages by less than 2% for all these groups. For black males, the effect of BMI is positive, and either increasing or non-linear in wages. For black females, the estimates tend to be more uniform across the wage distribution. I discuss possible explanations for these inter-quantile differences including preference discrimination, productivity differences, and statistical discrimination. The results point to a new explanation for the observed correlation between socioeconomic status and body weight: individuals with higher income earning potential have differential incentives to maintain a lower BMI.

Is decision-making ability related to food choice and facets of eating behaviour in adolescents?

PURPOSE

To test the prediction that poor decision-making would predict poor eating-related behaviours, which in turn would relate to elevated body mass index (BMI) percentile.

METHODS

Associations among decision-making ability, eating behaviours, and BMI percentile were examined in a sample of 311 healthy male and female adolescents, aged 14-18 years. Structural equation modelling was used to test the proposed relationships.

RESULTS

The predicted model was a good fit to the data and all paths between latent and indicator variables were significant. Impulsive responding significantly predicted poor food choice and overeating. No significant relationships emerged between eating-related variables and BMI percentile.

CONCLUSIONS

Findings from this study extend the existing research in adults and offer a more comprehensive understanding of factors that may contribute to eating behaviours and weight status in teenagers.

High body mass index is associated with impaired cognitive control

The prevalence of weight problems is increasing worldwide. There is growing evidence that high body mass index (BMI) is associated with frontal lobe dysfunction and cognitive deficits concerning mental flexibility and inhibitory control efficiency. The present study aims at replicating and extending these observations. We compared cognitive control performance of normal weight (BMI < 25) and overweight (BMI ≥ 25) university students on a task tapping either inhibitory control (Experiment 1) or interference control (Experiment 2). Experiment 1 replicated previous findings that found less efficient inhibitory control in overweight individuals. Experiment 2 complemented these findings by showing that cognitive control impairments associated with high BMI also extend to the ability to resolve stimulus-induced response conflict and to engage in conflict-driven control adaptation. The present results are consistent with and extend previous literature showing that high BMI in young, otherwise healthy individuals is associated with less efficient cognitive control functioning.

Not so fast: The impact of impulsivity on weight loss varies by treatment type

Behavioral weight loss (BWL) treatments result in suboptimal weight losses for many individuals. Impulsivity appears to be a maintenance factor of obesity, yet few studies have examined impulsivity as a predictor of outcomes from BWL. We examined specific facets of impulsivity (inhibitory control and delay discounting) as moderators of outcome in BWL. Overweight adults (n = 190) were randomized to standard behavioral treatment (SBT) or acceptance-based behavioral treatment (ABT). We hypothesized that impulsivity would be inversely associated with weight loss, and that the association between impulsivity and outcome would be attenuated in the ABT condition. Poorer general inhibitory control predicted lower percent weight lost at 12 months across conditions at the trend level (b = -0.003, p = 0.06). The negative impact of low inhibitory control on weight loss was attenuated by assignment to ABT versus SBT (b = 0.004, p = 0.03). Treatment condition, at trend level, also moderated the impact of delay discounting (b = -0.011, p = .098) and food-specific inhibitory control (b = 0.003, p = 0.06) on percent weight loss such that those with greater impulsivity benefitted most from ABT. Results reveal a potential pattern that impulsivity reduces benefit derived from SBT but not ABT. Further research on the moderating effect of impulsivity is necessary to inform the development of targeted treatments for clinically meaningful subtypes of patients.

Executive function in weight loss and weight loss maintenance: a conceptual review and novel neuropsychological model of weight control

Weight loss maintenance is a complex, multifaceted process that presents a significant challenge for most individuals who lose weight. A growing body of literature indicates a strong relationship between cognitive dysfunction and excessive body weight, and suggests that a subset of high-order cognitive processes known as executive functions (EF) likely play an important role in weight management. Recent reviews cover neuropsychological correlates of weight status yet fail to address the role of executive function in the central dilemma of successful weight loss maintenance. In this paper, we provide an overview of the existing literature examining executive functions as they relate to weight status and initial weight loss. Further, we propose a novel conceptual model of the relationships between EF, initial weight loss, and weight loss maintenance, mapping specific executive functions onto strategies known to be associated with both phases of the weight control process. Implications for the development of more efficacious weight loss maintenance interventions are discussed.

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.

The intersection of obesity and the longitudinal course of problem gambling

The purpose of this analysis was to assess the potential association between body mass index (BMI) and change in gambling symptom severity in a sample of non-treatment-seeking problem gamblers over a one year period. One-hundred sixty problem gamblers age 18-29 were recruited from the surrounding community and completed assessments of gambling behavior and related variables at baseline and one-year visits. Hierarchical multiple regression was used to examine the association between BMI and symptom change, while accounting for nicotine use, gender, age, and baseline gambling severity. The sample included 102 normal weight, 35 overweight, and 23 obese gamblers. Groups differed in sex, age, gambling risk level, and current nicotine use. There was a significant obesity x baseline gambling risk level interaction for the model predicting changes in GD-YBOCS scores over the 1-year follow-up. Obese participants with gambling disorder showed significantly smaller improvements in symptoms over one year than normal weight participants. Results suggest that obesity predicts smaller improvements in gambling symptoms over time in those meeting criteria for gambling disorder. Future research should clarify the possible influence of impulsivity on this association, and assess the clinical utility of weight management programs in treatments for gambling disorder.

Errors as a Means of Reducing Impulsive Food Choice

Nowadays, the increasing incidence of eating disorders due to poor self-control has given rise to increased obesity and other chronic weight problems, and ultimately, to reduced life expectancy. The capacity to refrain from automatic responses is usually high in situations in which making errors is highly likely. The protocol described here aims at reducing imprudent preference in women during hypothetical intertemporal choices about appetitive food by associating it with errors. First, participants undergo an error task where two different edible stimuli are associated with two different error likelihoods (high and low). Second, they make intertemporal choices about the two edible stimuli, separately. As a result, this method decreases the discount rate for future amounts of the edible reward that cued higher error likelihood, selectively. This effect is under the influence of the self-reported hunger level. The present protocol demonstrates that errors, well known as motivationally salient events, can induce the recruitment of cognitive control, thus being ultimately useful in reducing impatient choices for edible commodities.

A Cognitive Profile of Obesity and Its Translation into New Interventions

Change your lifestyle: decrease your energy intake and increase your energy expenditure, is what obesity experts tell people who need to lose weight. Though the advice might be correct, it appears to be extremely difficult to change one’s lifestyle. Unhealthy habits usually are ingrained and hard to change, especially for people with an “obese cognitive profile.” Knowledge of the cognitive mechanisms that maintain unhealthy eating habits is necessary for the development of interventions that can change behavior effectively. This paper discusses some cognitive processes that might maintain unhealthy eating habits and make healthier eating difficult, like increased food cue reactivity, weak executive skills and attention bias. An effort is also done to translate these basic scientific findings into new interventions which aim to tackle the sabotaging cognitive processes. Preliminary studies into the effectiveness of these interventions, if available, are presented.

Delayed reward discounting and grit in men and women with and without obesity

Objective

The objective of this study was to examine how sensitivity to short‐term reward and long‐term goal perseverance are related to body mass index (BMI; kg m²) in a large sample of men and women with and without obesity.

Methods

A total of 450 participants (56.2% male; 73.1% non‐Hispanic White) with mean ± standard deviation age of 30.7 ± 10.4 years and BMI of 29.3 ± 8.2 completed online versions of the Delayed Reward Discounting task to measure sensitivity to short‐term reward and the Grit Scale to measure long‐term goal perseverance.

Results

In regression analysis, higher sensitivity to short‐term reward (i.e. a preference for receiving smaller rewards after a shorter delay; b = 0.49, p = 0.016) and lower long‐term goal perseverance (b = −1.26, p = 0.042) were independently associated with higher BMIs. Individuals with a favourable score on one measure were not ‘protected’ from the risk associated with an unfavourable score on the other measure.

Conclusions

An overvaluation of short‐term reward (e.g. the taste of palatable food and the comfort of engaging in sedentary activities) and undervaluation of long‐term health goals (e.g. achieving a healthy weight and avoiding obesity‐related comorbidities) may contribute to excess weight. Additional research incorporating prospective experimental designs is needed to determine whether decision‐making strategies can be targeted to improve weight management.

Obesity and dissociable forms of impulsivity in young adults

OBJECTIVE

Obesity is one of the leading causes of preventable morbidity and mortality, and young people are increasingly affected. The aim of this study was to examine relationships between obesity and dissociable forms of impulsivity in young adults.

METHODS

A group of young adults (511) was recruited from city areas in the United States using media advertisements. These young adults were administered careful and extensive clinical and neurocognitive assessment in order to quantify different aspects of impulsivity (behavioral/phenomenological-, cognitive-, and personality-related measures). Associations between obesity and impulsivity were explored using multivariate analysis of variance and discriminant function analysis.

RESULTS

10.8% of the sample was obese, and 21.5% was overweight. Compared to controls, subjects with obesity showed significantly elevated rates of maladaptive gambling behaviors, monetary amounts lost to gambling, nicotine consumption, impulsive action (prolonged stop-signal reaction times in the Stop-Signal Test), and impulsive decision-making (reduced modulation of behavior as a function of risk in the Cambridge Gamble Test). Even accounting for potential confounding variables, obesity was significantly predicted by female gender, older age, more maladaptive gambling behaviors, and worse inhibitory control (stop-signal reaction times).

CONCLUSION

Obesity is associated with several dissociable forms of impulsivity in young people, especially gambling and impulse dyscontrol. Family doctors should screen for gambling problems in obese young adults. Successful treatment of nicotine dependence in young obese people is likely to require intensive weight management support. Neuropsychological deficits relating to impulsivity occur in obese people in early adulthood, and may represent vulnerability markers rather than being due to chronic untoward metabolic effects on brain function.