Concurrent visuo-spatial processing reduces food cravings in prescribed weight-loss dieters

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

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

The effect of a mindfulness-based decentering strategy on chocolate craving

According to the elaborated-intrusion theory of desire, strategies that load visual working memory will reduce cravings. According to the grounded cognition theory of desire, cravings will be reduced with mindfulness-based decentering strategies that encourage individuals to see their thoughts as thoughts. However, decentering strategies also tend to load visual working memory making it difficult to test the latter prediction. This study addressed this issue by matching visualization across decentering and guided imagery tasks. Male and female participants (n = 101) underwent a chocolate craving induction before listening to a 4-min audio recording that guided them to (a) decenter from their thoughts and feelings, (b) engage in visualization, or (c) let their mind wander. Participants reported on chocolate craving before and after the craving induction and following the 4-min recording. They also provided retrospective reports of craving during the recording, reported on the extent to which they had adhered to the audio instructions and briefly indicated what they had been thinking about during the recording. Results showed a significant reduction in cravings to baseline following the recording across all three conditions (p < .001), but no significant differences between conditions or in the retrospective reports of craving. There was some evidence to suggest that participants in the mind wandering condition had been thinking about alternate goals, which may have inhibited thoughts about chocolate and been just as effective at reducing craving as the imagery and decentering strategies. Exploratory analyses showed a trend toward decentering being more effective than imagery where participants reported higher task adherence throughout the 4 min (p = .067). This raises the possibility that decentering effects may be improved with better strategy adherence, which might be achieved through practice or increased motivation.

Dynamic fMRI networks predict success in a behavioral weight loss program among older adults

More than one-third of adults in the United States are obese, with a higher prevalence among older adults. Obesity among older adults is a major cause of physical dysfunction, hypertension, diabetes, and coronary heart diseases. Many people who engage in lifestyle weight loss interventions fail to reach targeted goals for weight loss, and most will regain what was lost within 1-2 years following cessation of treatment. This variability in treatment efficacy suggests that there are important phenotypes predictive of success with intentional weight loss that could lead to tailored treatment regimen, an idea that is consistent with the concept of precision-based medicine. Although the identification of biochemical and metabolic phenotypes are one potential direction of research, neurobiological measures may prove useful as substantial behavioral change is necessary to achieve success in a lifestyle intervention. In the present study, we use dynamic brain networks from functional magnetic resonance imaging (fMRI) data to prospectively identify individuals most likely to succeed in a behavioral weight loss intervention. Brain imaging was performed in overweight or obese older adults (age: 65-79 years) who participated in an 18-month lifestyle weight loss intervention. Machine learning and functional brain networks were combined to produce multivariate prediction models. The prediction accuracy exceeded 95%, suggesting that there exists a consistent pattern of connectivity which correctly predicts success with weight loss at the individual level. Connectivity patterns that contributed to the prediction consisted of complex multivariate network components that substantially overlapped with known brain networks that are associated with behavior emergence, self-regulation, body awareness, and the sensory features of food. Future work on independent datasets and diverse populations is needed to corroborate our findings. Additionally, we believe that efforts can begin to examine whether these models have clinical utility in tailoring treatment.

Desensitizing Addiction: Using Eye Movements to Reduce the Intensity of Substance-Related Mental Imagery and Craving

Eye movement desensitization and reprocessing (EMDR) is an effective treatment for posttraumatic stress disorder. During this treatment, patients recall traumatic memories while making horizontal eye movements (EM). Studies have shown that EM not only desensitize negative memories but also positive memories and imagined events. Substance use behavior and craving are maintained by maladaptive memory associations and visual imagery. Preliminary findings have indicated that these mental images can be desensitized by EMDR techniques. We conducted two proof-of-principle studies to investigate whether EM can reduce the sensory richness of substance-related mental representations and accompanying craving levels. We investigated the effects of EM on (1) vividness of food-related mental imagery and food craving in dieting and non-dieting students and (2) vividness of recent smoking-related memories and cigarette craving in daily smokers. In both experiments, participants recalled the images while making EM or keeping eyes stationary. Image vividness and emotionality, image-specific craving and general craving were measured before and after the intervention. As a behavioral outcome measure, participants in study 1 were offered a snack choice at the end of the experiment. Results of both experiments showed that image vividness and craving increased in the control condition but remained stable or decreased after the EM intervention. EM additionally reduced image emotionality (experiment 2) and affected behavior (experiment 1): participants in the EM condition were more inclined to choose healthy over unhealthy snack options. In conclusion, these data suggest that EM can be used to reduce intensity of substance-related imagery and craving. Although long-term effects are yet to be demonstrated, the current studies suggest that EM might be a useful technique in addiction treatment.

Playing Tetris decreases drug and other cravings in real world settings

Most research on cognitive processes in craving has been carried out in the laboratory and focuses on food craving. This study extends laboratory findings to real world settings and cravings for drugs or activities as well as food. Previous laboratory research has found that playing Tetris reduces craving strength. The present study used an ecological momentary assessment protocol in which 31 undergraduate participants carried iPods for a week and were prompted 7 times each day, by SMS message, to use their iPod to report craving. Participants reported craving target and strength (0-100), whether they indulged their previous craving (yes/no), and whether they were under the influence of alcohol (yes/no). Those randomly assigned to the intervention condition (n=15) then played Tetris for 3min and reported their craving again. Those in the monitoring-only control condition (n=16) provided baseline craving data to test if Tetris reduced the incidence and strength of spontaneous cravings across the week. Playing Tetris decreased craving strength for drugs (alcohol, nicotine, caffeine), food and drink, and activities (sex, exercise, gaming), with a mean reduction of 13.9 percentage points, effect size f(2)=0.11. This effect was consistent across the week. This is the first demonstration that visual cognitive interference can be used in the field to reduce cravings for substances and activities other than eating.

The Elaborated Intrusion Theory of desire: a 10-year retrospective and implications for addiction treatments

INTRODUCTION

Ten years after the publication of Elaborated Intrusion (EI) Theory, there is now substantial research into its key predictions. The distinction between intrusive thoughts, which are driven by automatic processes, and their elaboration, involving controlled processing, is well established. Desires for both addictive substances and other desired targets are typically marked by imagery, especially when they are intense. Attention training strategies such as body scanning reduce intrusive thoughts, while concurrent tasks that introduce competing sensory information interfere with elaboration, especially if they compete for the same limited-capacity working memory resources.

CONCLUSION

EI Theory has spawned new assessment instruments that are performing strongly and offer the ability to more clearly delineate craving from correlated processes. It has also inspired new approaches to treatment. In particular, training people to use vivid sensory imagery for functional goals holds promise as an intervention for substance misuse, since it is likely to both sustain motivation and moderate craving.

Drive for consumption, craving, and connectivity in the visual cortex during the imagery of desired food

There is considerable interest in understanding food cravings given the obesogenic environment of Western Society. In this paper we examine how the imagery of palatable foods affects cravings and functional connectivity in the visual cortex for people who differ on the power of food scale (PFS). Fourteen older, overweight/obese adults came to our laboratory on two different occasions. Both times they ate a controlled breakfast meal and then were restricted from eating for 2.5 h prior to scanning. On 1 day they consumed a BOOST(®) liquid meal after the period of food restriction, whereas on the other day they only consumed water (NO BOOST(®) condition). After these manipulations, they had an fMRI scan in which they were asked to image both neutral objects and their favorite snack foods; they also completed visual analog scales for craving, hunger, and the vividness of the imagery experiences. Irrespective of the BOOST(®) manipulation, we observed marked increases in food cravings when older, overweight/obese adults created images of favorite foods in their minds as opposed to creating an image of neutral objects; however, the increase in food craving following the imagery of desired food was more pronounced among those scoring high than low on the PFS. Furthermore, local efficiency within the visual cortex when imaging desired food was higher for those scoring high as compared to low on the PFS. The active imagery of desired foods seemed to have overpowered the BOOST(®) manipulation when evaluating connectivity in the visual cortex.

Examining the relationship between food thought suppression and binge eating disorder

Food thought suppression, or purposely attempting to avoid thoughts of food, is related to a number of unwanted eating- and weight-related consequences, particularly in dieting and obese individuals. Little is known about the possible significance of food thought suppression in clinical samples, particularly obese patients who binge eat. This study examined food thought suppression in 150 obese patients seeking treatment for binge eating disorder (BED). Food thought suppression was not associated with binge eating frequency or body mass index but was significantly associated with higher current levels of eating disorder psychopathology and variables pertaining to obesity, dieting, and binge eating.

Olfactory stimulation curbs food cravings

Based on the logic of mutual competition between cravings and odours for limited-capacity resources, this study investigated whether a simple olfactory task, involving a brief odour exposure, could reduce food cravings. In support, Experiment 1 showed that smelling a neutral unfamiliar odorant reduced cravings for highly desired food items, relative to a comparison auditory task and a no-task control condition. Experiment 2 replicated these findings specifically for chocolate cravings, which can be particularly problematic. Thus olfactory stimulation offers potential scope for curbing unwanted food cravings.

Factor structure and clinical correlates of the Food Thought Suppression Inventory within treatment seeking obese women with binge eating disorder

Prior research on the relations among eating behaviors and thought suppression is limited to a measure of general thought suppression, the White Bear Suppression Inventory. To address this limitation, researchers recently validated the Food Thought Suppression Inventory (FTSI). Analyses using this measure suggest that food thought suppression is distinct from and is more predictive of eating disorder psychopathology than is general thought suppression. The FTSI, however, has not yet been validated in clinical samples. The purpose of the current study is to examine the factor structure and clinical correlates of the FTSI within treatment seeking obese women with binge eating disorder (BED; N=128). Analyses revealed a valid and reliable one-factor measure of food thought suppression that was related to higher levels of eating and general psychopathology. The findings provide evidence for the use of the FTSI with obese women with BED. Future research should examine the psychometric properties of the FTSI within larger and more diverse samples.

Desire

Traditionally, self-control research has put a strong focus on the mechanisms that support the control of behavior in the face of temptation. This emphasis in the field has led to some neglect of desire as an impelling force that needs to be controlled. However, the focus appears to be shifting, as recent research has led to novel insights into the nature of desire. In this review, we integrate these insights into how desire emerges, how it operates, and how it may best be controlled. Drawing on competitive-access models of working memory and dynamical reprocessing models, we highlight, among other factors, the role of top-down attentional resources in preventing the early conscious processing and subsequent escalation of desire.

Food thought suppression: a matched comparison of obese individuals with and without binge eating disorder

Preliminary studies of non-clinical samples suggest that purposely attempting to avoid thoughts of food, referred to as food thought suppression, is related to a number of unwanted eating- and weight-related consequences, particularly in obese individuals. Despite possible implications for the treatment of obesity and eating disorders, little research has examined food thought suppression in obese individuals with binge eating disorder (BED). This study compared food thought suppression in 60 obese patients with BED to an age-, gender-, and body mass index (BMI)-matched group of 59 obese persons who do not binge eat (NBO). In addition, this study examined the associations between food thought suppression and eating disorder psychopathology within the BED and NBO groups and separately by gender. Participants with BED and women endorsed the highest levels of food thought suppression. Food thought suppression was significantly and positively associated with many features of ED psychopathology in NBO women and with eating concerns in men with BED. Among women with BED, higher levels of food thought suppression were associated with higher frequency of binge eating, whereas among men with BED, higher levels of food thought suppression were associated with lower frequency of binge eating. Our findings suggest gender differences in the potential significance of food thought suppression in obese groups with and without co-existing binge eating problems.

Intentional weight loss in overweight and obese individuals and cognitive function: a systematic review and meta-analysis

High adiposity in middle age is associated with higher dementia risk. The association between weight loss and cognitive function in older adults is still controversial. A meta-analysis was undertaken to estimate the effectiveness of intentional weight loss on cognitive function in overweight and obese adults. A structured strategy was used to search randomized and non-randomized studies reporting the effect of intentional and significant weight loss on cognitive function in overweight and obese subjects. Information on study design, age, nutritional status, weight-loss strategy, weight lost and cognitive testing was extracted. A random-effect meta-analysis was conducted to obtain summary effect estimates for memory and attention-executive domains. Twelve studies met inclusion criteria. Seven were randomized trials and the remaining five included a control group. A low-order significant effect was found for an improvement in cognitive performance with weight loss in memory (effect size 0.13, 95% CI 0.00-0.26, P=0.04) and attention/executive functioning (effect size 0.14, 95% CI 0.01-0.27, P<0.001). Studies were heterogeneous in study design, sample selection, weight-loss intervention and assessment of cognitive function. Weight loss appears to be associated with low-order improvements in executive/attention functioning and memory in obese but not in overweight individuals.

A Cognitive Experimental Approach to Understanding and Reducing Food Cravings

Food cravings are a common everyday experience. Yet, they can pose significant health risks for some people. Following initial investigations into the phenomenology, antecedents, and consequences of food cravings, recent scientific interest has turned to the underpinnings of the actual craving experience. In this article, we outline a conceptual framework for studying food cravings that is grounded in cognitive experimental psychology and describe our corresponding program of research. In particular, we present converging evidence from a number of seemingly disparate lines of research into the cognitive processes that underlie food cravings with a view to developing a craving-reduction technique.

Visuospatial tasks suppress craving for cigarettes

The Elaborated Intrusion (EI) theory of desire posits that visual imagery plays a key role in craving. We report a series of experiments testing this hypothesis in a drug addiction context. Experiment 1 showed that a mental visual imagery task with neutral content reduced cigarette craving in abstaining smokers, but that an equivalent auditory task did not. The effect of visual imagery was replicated in Experiment 2, which also showed comparable effects of non-imagery visual working memory interference. Experiment 3 showed that the benefit of visual over auditory interference was not dependent upon imagery being used to induce craving. Experiment 4 compared a visuomotor task, making shapes from modeling clay, with a verbal task (counting back from 100), and again showed a benefit of the visual over the non-visual task. We conclude that visual imagery supports craving for cigarettes. Competing imagery or visual working memory tasks may help tackle craving in smokers trying to quit.

Intrusive images in psychological disorders: characteristics, neural mechanisms, and treatment implications

Involuntary images and visual memories are prominent in many types of psychopathology. Patients with posttraumatic stress disorder, other anxiety disorders, depression, eating disorders, and psychosis frequently report repeated visual intrusions corresponding to a small number of real or imaginary events, usually extremely vivid, detailed, and with highly distressing content. Both memory and imagery appear to rely on common networks involving medial prefrontal regions, posterior regions in the medial and lateral parietal cortices, the lateral temporal cortex, and the medial temporal lobe. Evidence from cognitive psychology and neuroscience implies distinct neural bases to abstract, flexible, contextualized representations (C-reps) and to inflexible, sensory-bound representations (S-reps). We revise our previous dual representation theory of posttraumatic stress disorder to place it within a neural systems model of healthy memory and imagery. The revised model is used to explain how the different types of distressing visual intrusions associated with clinical disorders arise, in terms of the need for correct interaction between the neural systems supporting S-reps and C-reps via visuospatial working memory. Finally, we discuss the treatment implications of the new model and relate it to existing forms of psychological therapy.

Managing anxiety in eating disorders with knitting

OBJECTIVE

Recovery from anorexia nervosa (AN) is often confounded by intrusive, anxious preoccupations with control of eating, weight and shape. These are distressing and represent a potential barrier to psychological change. Theoretical and empirical evidence suggests that performing a concurrent visuospatial task reduces the emotional intensity of distressing images. We assessed whether the visuospatial task of knitting influences the anxious preoccupation experienced by inpatients with AN.

METHOD

Prospective interventional cohort.

SUBJECTS

Thirty-eight women with AN admitted to a specialized eating disorder unit.

INTERVENTION

All subjects were given knitting lessons and free access to supplies.

MEASURE

Subjects were asked to report the qualitative effects of knitting on their psychological state using a self-report questionnaire.

RESULTS

Patients reported a subjective reduction in anxious preoccupation when knitting. In particular, 28/38 (74%) reported it lessened the intensity of their fears and thoughts and cleared their minds of eating disorder preoccupations, 28/38 (74%) reported it had a calming and therapeutic effect and 20/38 (53%) reported it provided satisfaction, pride and a sense of accomplishment.

DISCUSSION

This preliminary data suggests that knitting may benefit inpatients with eating disorders by reducing their anxious preoccupations about eating, weight and shape control. The specificity of this effect is yet to be determined. This preliminary outcome requires further controlled study in AN subjects. From a clinical perspective, knitting is inexpensive, easily learned, can continue during social interaction, and can provide a sense of accomplishment. The theoretical and empirical rationale for this observation, and implications for deriving alternative strategies to augment treatment in AN, are discussed.