It is a matter of perspective: Attentional focus rather than dietary restraint drives brain responses to food stimuli.

Brain responses to food are thought to reflect food's rewarding value and to fluctuate with dietary restraint. We propose that brain responses to food are dynamic and depend on attentional focus. Food pictures (high-caloric/low-caloric, palatable/unpalatable) were presented during fMRI-scanning, while attentional focus (hedonic/health/neutral) was induced in 52 female participants varying in dietary restraint. The level of brain activity was hardly different between palatable versus unpalatable foods or high-caloric versus low-caloric foods. Activity in several brain regions was higher in hedonic than in health or neutral attentional focus (p < .05, FWE-corrected). Palatability and calorie content could be decoded from multi-voxel activity patterns (p < .05, FDR-corrected). Dietary restraint did not significantly influence brain responses to food. So, level of brain activity in response to food stimuli depends on attentional focus, and may reflect salience, not reward value. Palatability and calorie content are reflected in patterns of brain activity.

Effects of a health versus hedonic mindset on daily-life snacking behaviour.

BACKGROUND: In today's obesogenic environment high-caloric palatable foods are omnipresent, making it hard for many to reach and maintain a healthy body weight. This study investigates the effects of a health versus hedonic mindset on daily-life snacking behaviour. The hypothesis is that a health mindset leads to reduced snacking behaviour compared to a hedonic mindset. This effect is expected to be most pronounced with high dietary restraint and least pronounced with high trait self-control. METHODS: For 3 weeks, degree of craving and amount of snacks that were craved and consumed were assessed four times a day, using smartphone Ecological Momentary Assessment (EMA). A total of 111 female participants (body mass index range: 20-23.5) were randomly assigned to a 1-week health (n = 53) or hedonic (n = 58) mindset, occurring in week 2 of the EMA protocol. The mindset manipulations consisted of text messages, focusing either on the enjoyment of tasty food (hedonic) or on healthy living and eating (health). RESULTS: contrary to our hypotheses, mindset did not affect snacking behaviour. Instead, degree of craving and intake of snacks reduced significantly over time, not moderated by mindset, dietary restraint (Restraint Scale) or trait self-control (Brief Self-Control Scale). Importantly, this was not due to reduced compliance. Possibly, the reduced craving and snacking behaviour were due to monitoring and/or socially desirable answering tendencies. Additional time point analyses showed that craving was strongest in the late afternoon (3:30-5:00 PM), and-across mindset conditions-degree of craving correlated negatively with trait self-control. CONCLUSIONS: future studies could manipulate degree of monitoring and design individually tailored manipulations.

More complex than you might think: Neural representations of food reward value in obesity.

Obesity reached pandemic proportions and weight-loss treatments are mostly ineffective. The level of brain activity in the reward circuitry is proposed to be proportionate to the reward value of food stimuli, and stronger in people with obesity. However, empirical evidence is inconsistent. This may be due to the double-sided nature of high caloric palatable foods: at once highly palatable and high in calories (unhealthy). This study hypothesizes that, viewing high caloric palatable foods, a hedonic attentional focus compared to a health and a neutral attentional focus elicits more activity in reward-related brain regions, mostly in people with obesity. Moreover, caloric content and food palatability can be decoded from multivoxel patterns of activity most accurately in people with obesity and in the corresponding attentional focus. During one fMRI-session, attentional focus (hedonic, health, neutral) was manipulated using a one-back task with individually tailored food stimuli in 32 healthy-weight people and 29 people with obesity. Univariate analyses (p < 0.05, FWE-corrected) showed that brain activity was not different for palatable vs. unpalatable foods, nor for high vs. low caloric foods. Instead, this was higher in the hedonic compared to the health and neutral attentional focus. Multivariate analyses (MVPA) (p < 0.05, FDR-corrected) showed that palatability and caloric content could be decoded above chance level, independently of either BMI or attentional focus. Thus, brain activity to visual food stimuli is neither proportionate to the reward value (palatability and/or caloric content), nor significantly moderated by BMI. Instead, it depends on people's attentional focus, and may reflect motivational salience. Furthermore, food palatability and caloric content are represented as patterns of brain activity, independently of BMI and attentional focus. So, food reward value is reflected in patterns, not levels, of brain activity.

Effects of Mindset and Dietary Restraint on Attention Bias for Food and Food Intake.

Evidence for attention bias (AB) for food in restrained eaters is inconsistent. A person's mindset related to food - that is, whether someone focuses on the hedonic or health aspects of food - might be an overlooked influence on AB for food, possibly explaining the inconsistency in the literature. Fluctuations between a hedonic versus a health mindset might be strongest in restrained eaters, who have a conflicted relationship with food. We investigated the effect of mindset and dietary restraint on AB for food and food intake. We hypothesized that AB for food, as reflected in eye-movement measures and manual response latencies, as well as food intake, would be larger in the hedonic than in the health mindset, most strongly in participants scoring high on dietary restraint. Moreover, we expected a positive correlation between AB for food and food intake, especially in the hedonic mindset. We used short video clips to induce either a health or hedonic mindset. Subsequently, participants (n = 122) performed a modified additional singleton task with pictures of high-caloric food vs neutral pictures as irrelevant distractors. Next, food intake was measured in a bogus taste test. We found no evidence for an AB towards food, nor any moderation by either mindset or dietary restraint. Food intake tended to be higher for participants scoring higher on dietary restraint, but effects were not moderated by mindset. Response-latency based AB for food tended to correlate positively with food intake in the hedonic mindset. Taken together, our hypotheses regarding AB for food were largely not confirmed. We provide suggestions on how to improve upon the specific implementations of our AB task and mindset manipulation, to strengthen future research in this field.

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

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