Food-Pics_Extended-An Image Database for Experimental Research on Eating and Appetite: Additional Images, Normative Ratings and an Updated Review

Encouraging online consumers into making better food choices: The power of nature exposure on healthy food choices

BACKGROUND

online environments can influence food desire and choices. We tested if online calming nature and stressful street environments can affect desire for healthy and unhealthy foods.

METHOD

we asked 238 participants (40 ± 14 yrs) to rate their desire (100 mm VAS) for 7 low calorie nutrient rich foods (Healthy) and 7 high calorie nutrient poor foods (Unhealthy), and perceived stress (state anxiety in STAI), before and after imagining themselves in a control, nature park, or busy street condition.

RESULTS

participants who imagined themselves being in a nature park had a significant higher desire for Healthy foods, than participants in the busy street condition (p < 0.05). Participants in the busy street condition decreased their desire for Healthy foods after they imagined themselves in a busy street (p < 0.05)). However, perceived stress did not impact the association between condition and desire for low calorie foods nor high calorie foods.

CONCLUSION

this study suggests that online environments can have an impact on healthy food desires, which could be of importance for the increased number of food choices which are made in online environments.

Creation and validation of a NOVA scored picture set to evaluate ultra-processed foods

There has been a rapid shift in the modern food environment towards increased processing in foods consumed in the United States (US) and globally. The NOVA system (not an acronym) for classifying food on degree of processing currently has the most empirical support. Consumption of foods in the NOVA 4 category, ultra-processed foods (UPF), is a risk factor for a host of poor health outcomes including heart disease, stroke, and cancer. Despite these poor health outcomes, UPF make up 58% of calories consumed in the US. Methodologies for assessing the reinforcing and rewarding properties of these foods are necessary tools. The Becker-DeGroot-Marschak auction paradigm (BDM) is a well validated tool for measuring value and is amenable to neuromonitoring environments. To allow for the testing of hypotheses based on level of food processing, we present a picture set of 14 UPF and 14 minimally-processed foods (MPF) matched on visual properties, food characteristics (fat, carbohydrate, cost, etc.), and rated perceptual properties. Further, we report our scoring of these foods using the NOVA classification system and provide additional data from credentialed nutrition professionals and on inter-rater reliability using NOVA, a critique of the system. Finally, we provide all pictures, data, and code used to create this picture set as a tool for researchers.

Seeing is misbelieving: Consumers wrongly believe that unhealthy food tastes better when there is more of it

Recent studies have shown that people can believe that unhealthy foods taste better, even if healthy and unhealthy foods are equally as tasty. Specifically, when tasty and unhealthy foods are frequent in one context but rare in another, people perceive unhealthy foods to taste better, even if health and taste are unrelated. Given that people often consume food in one context, the current study investigated whether false beliefs about the health-taste relationship in foods can also occur in just one single context, in which either healthy or unhealthy foods are predominant, when there is no contrasting context where the respective other food is predominant. In two experiments (N = 342), we presented participants with pictures of meals from a single context and varied the frequency of healthy and unhealthy foods between participants. Although healthy and unhealthy foods tasted equally as good, participants believed that (un)healthy foods tasted better when there were more of them. This research demonstrates that health-taste beliefs might be changed by increasing the relative frequency of healthy foods in the environment overall, not by just offering some healthy and tasty foods.

Time-restricted feeding can increase food-related impulsivity: a randomized controlled trial

OBJECTIVES

Although an increasing number of studies show that time-restricted feeding may improve metabolic health, studies examining the behavioral effects of this eating pattern are limited. This study examined the effect of time-restricted feeding on impulsivity in adults.

METHODS

Thirty adults aged 25-41 years participated in this randomized controlled trial. The intervention group followed time-restricted feeding for 4 weeks and there was no energy restriction in the intervention group (n = 15) or control group (n = 15). Impulsivity was assessed before and after the intervention with the Barratt Impulsiveness Scale and the Go/NoGo task.

RESULTS

The compliance rate (the percentage of days when participants had a feeding time of ≤ 8 hours/day) of the intervention group to the time-restricted feeding pattern was 92.38 ± 4.24%. The Barratt Impulsiveness Scale-11 total score of the intervention group increased from 55.53 ± 6.37 to 59.47 ± 7.67 (p = 0.02). During the Go/NoGo task, an indicator of inhibitory control, the reaction time to food and non-food stimuli was significantly shortened in the intervention group (respectively; p = 0.009, p = 0.01). In the control group, no significant change was detected in impulsivity determined by the BIS-11 or Go/NoGo task.

DISCUSSION

This study showed that although time-restricted feeding may reduce body weight, it can lead to increased impulsivity and impaired inhibitory control.Trial registration: ClinicalTrials.gov identifier: NCT04960969.

Individuals vary in their overt attention preference for positive images consistently across time and stimulus types

What humans look at strongly determines what they see. We show that individual differences in the tendency to look at positive stimuli are stable across time and across contents, establishing gaze positivity preference as a perceptual trait that determines the amount of positively valence stimuli individuals select for visual processing. Furthermore, we show that patients with major depressive disorder exhibit consistently low positivity preference before treatment. In a subset of patients, we also assessed the positivity preference after two months of treatment in which positivity gaze preference increased to levels similar to healthy individuals. We discuss the possible practical diagnostic applications of these findings, as well as how this general gaze-related trait may influence other behavioral and psychological aspects.

Effects of (non)deceptive placebos on reported sleep quality and food cue reactivity

A lack of sleep can increase appetite, particularly for high-calorie food. The current study tested the effects of an open-label placebo for improving sleep quality and reducing food cue reactivity. In open-label placebo interventions, placebo recipients are informed that they are receiving a placebo without a pharmacologically active substance. Participants (n = 150) were randomly allocated to one of three groups that received either an open-label placebo to improve sleep quality, a deceptive placebo ("melatonin"), or no placebo. The placebo was administered daily before bedtime for 1 week. Sleep quality and reactivity to high-calorie food cues (appetite, visual attention to food images) were assessed. The deceptive placebo (but not the open-label placebo) reduced reported sleep-onset latency. The open-label placebo decreased perceived sleep efficiency. The placebo interventions did not change food cue reactivity. This study demonstrated that open-label placebos do not present an alternative to deceptive placebos for improving sleep quality. The undesirable open-label placebo effects found warrant further exploration.

The impact of food stimuli and fasting on cognitive control in task switching

Previous research demonstrated motivation-control interactions in task switching. However, motivational effects on switch costs have been mostly examined using monetary rewards. Here, we investigated whether stimulus material linked to food and fasting affect control processes in task switching. We predicted that switching to the task comprising food stimuli would be facilitated, which should result in lower switch costs for this task, and that these effects would be stronger with higher motivational salience of the food stimuli, i.e. in hungry individuals and/or individuals with restrictive eating. Participants switched between categorising food items as sweet or savoury and digits as odd or even in two task-switching paradigms: an alternating runs and a voluntary task switching. Hunger was induced by 14 h fasting in the experimental compared to the control group. Results showed lower switch costs for the motivational-affective food task in both task-switching paradigms and in both groups. Switch costs for the neutral digit task were significantly higher in the fasting group compared to the control group in alternating runs task switching only. Individual differences in restrictive eating were related negatively but not significantly to the size of the switch costs. All in all, the results demonstrate an impact of motivational-affective stimuli on cognitive control in task switching and suggest a potential modulatory role of motivational states, though the findings need to be replicated.

Naturalistic food categories are driven by subjective estimates rather than objective measures of food qualities

Food-related studies often categorize foods using criteria such as fat and sugar content (e.g., high-fat, high-sugar foods; low-fat, low-sugar foods), and use these categorizations for further analyses. While these criteria are relevant to nutritional health, it is unclear whether they agree with the ways in which we typically group foods. Do these objective categories correspond to our subjective sense? To address this question, we recruited a group of 487 online participants to perform a triplet comparison task involving implicit object similarity judgements on images of 36 foods, which varied in their levels of fat and sugar. We also acquired subjective ratings of other food properties from another set of 369 online participants. Data from the online triplet task was used to generate a similarity matrix of these 36 foods. Principal Components Analysis (PCA) of this matrix identified that the strongest determinant of food similarity (the first PC) was most highly related to participants' judgements of how processed the foods were, while the second component was most related to estimates of sugar and fat content. K-means clustering analysis revealed five emergent food groupings along these PC axes: sweets, fats, starches, fruits, and vegetables. Our results suggest that naturalistic categorizations of food are driven primarily by knowledge of the origin of foods (i.e., grown or manufactured), rather than by their sensory or macronutrient properties. These differences should be considered and explored when developing methods for scientific food studies.

Effects of hunger and calorie content on visual awareness of food stimuli

Calorie content and hunger are two fundamental cues acting upon the processing of visually presented food items. However, whether and to which extent they affect visual awareness is still an open question. Here, high- and low-calorie food images administered to hungry or satiated participants were confronted in a breaking-Continuous Flash Suppression paradigm (Experiment 1), measuring the time required to access to visual awareness, and in a Binocular Rivalry paradigm (Experiment 2), quantifying the dominance time in visual awareness. Experiment 1 showed that high-calorie food accessed faster visual awareness, but mostly in satiated participants. Experiment 2 indicated that high-calorie food dominated longer visual awareness, regardless the degree of hunger. We argued that the unconscious advantage (Experiment 1) would represent a default state of the visual system towards highest-energy nutrients, yet the advantage is lost in hunger so to be tuned towards an increased need for any nutritional category. On the other hand, the conscious advantage of high-calorie food (Experiment 2) would represent a conscious perceptual and attentional bias towards highest energy-dense food useful for the actual detection of these stimuli in the environment.

Imagine chocolate: The craving experience questionnaire in the food domain

Measurement of food craving has gained relevance in the current obesity epidemic. The Craving Experience Questionnaire (CEQ) considers not only craving intensity but also cognitive intrusiveness and imagery vividness as separate craving factors and could thus refine food craving assessment. It is available in two versions with ten items each. The CEQ-F assesses craving frequency across specific time periods and the CEQ-S time-point specific craving strength. Across three independent studies, N = 533 participants completed the German chocolate CEQ-F referenced at the past year to operationalise trait-like craving. Among them, N = 402 also completed the German chocolate CEQ-S referenced at the current moment to operationalise state-like craving. Four-week test-retest reliability was measured. For external validity, we assessed self-reported chocolate consumption, body-mass-index, trait approach motivation, general imagery vividness, and the most widely used food craving questionnaire, namely the Food Cravings Questionnaires in a trait (FCQ-T-r) and state version (FCQ-S), as well as behavioural approach bias (reaction time-based measurement). The three-factor structure was replicated with excellent internal consistency for both CEQ-F and CEQ-S. Test-retest reliability was moderate for both CEQ versions. CEQ-F scores were related to higher levels of chocolate consumption, approach motivation, and FCQ-T-r scores, but not to body-mass-index, imagery vividness, or approach bias. CEQ-S scores were associated with FCQ-S scores and partly with approach bias, but not with approach motivation and imagery vividness. The current results support the factor structure, validity and reliability of the German chocolate CEQ-S and CEQ-F with questions remaining regarding the ability of the CEQ-S to measure state craving. Thus, CEQ-F and CEQ-S usefully contribute to food craving assessment.

The role of visual working memory in capacity-limited cross-modal ensemble coding

Ensemble coding refers to the brain's ability to rapidly extract summary statistics, such as average size and average cost, from a large set of visual stimuli. Although ensemble coding is thought to circumvent a capacity limit of visual working memory, we recently observed a VWM-like capacity limit in an ensemble task where observers extracted the average sweetness of groups of food pictures (i.e., they could only integrate information from four out of six available items), thus suggesting the involvement of VWM in this novel form of cross-modal ensemble coding. Therefore, across two experiments we investigated if this cross-modal ensemble capacity limit could be explained by individual differences in VWM processing. To test this, observers performed both an ensemble task and a VWM task, and we determined 1) how much information they integrated into their ensemble percepts, and 2) how much information they remembered from those displays. Interestingly, we found that individual differences in VWM capacity did not explain differences in performance on the ensemble coding task (i.e., high-capacity individuals did not have significantly higher "ensemble abilities" than low-capacity individuals). While our data cannot definitively state whether or not VWM is necessary to perform the ensemble task, we conclude that it is certainly not sufficient to support this cognitive process. We speculate that the capacity limit may be explained by 1) a bottleneck at the perceptual stage (i.e., a failure to process multiple visual features across multiple items, as there are no singular features that convey taste), or 2) the interaction of multiple cognitive systems (e.g., VWM, gustatory working memory, long term memory). Our results highlight the importance of examining ensemble perception across multiple sensory and cognitive domains to provide a clearer picture of the mechanisms underlying everyday behavior.

Consequences of positive vs. negative information concerning the amount of sugar consumption on appetite, mood, and visual food cue attention: Findings from two online interventions

BACKGROUND

Eating too much sugar is associated with many negative health effects. Two brief online interventions were carried out to investigate whether information about the negative consequences of eating high-sugar food vs. positive consequences of eating low-sugar food can change reported appetite, mood, and visual food cue attention.

METHOD

For Study I, participants (n = 201) were allocated to one of three groups: Two groups were asked to list either the negative consequences of high-sugar consumption (negative focus) or the positive consequences of low-sugar consumption (positive focus). The third group carried out a control task (writing a shopping list). For Study II, 200 participants took part in a quiz with questions focusing on either positive, negative, or neutral consequences of high vs. low sugar consumption. Participants evaluated their appetite and mood before and after all interventions (list, quiz) and additionally completed a visual probe task with images depicting high vs. low-sugar food.

RESULTS

In Study I, the positive focus increased appetite for low-sugar food. The negative focus reduced participants' positive mood but did not change reported appetite. In Study II, all quiz conditions decreased appetite for high-sugar foods but did not affect mood. None of the interventions influenced visual attention to the food images.

CONCLUSION

Focusing on negative consequences of a high-sugar diet is less pleasant and is less effective in changing people's appetite than considering the positive aspects of a low-sugar diet. Thus, future interventions should instead spotlight the positive outcomes of a healthy diet.

Emotional food-cue-reactivity in anorexia nervosa and bulimia nervosa: An electroencephalography study

OBJECTIVE

Food-cue-reactivity entails neural and experiential responses to the sight and smell of attractive foods. Negative emotions can modulate such cue-reactivity and this might be central to the balance between restrictive versus bulimic symptomatology in Anorexia Nervosa (AN) and Bulimia Nervosa (BN).

METHOD

Pleasantness ratings and electrocortical responses to food images were measured in patients with AN (n = 35), BN (n = 32) and matched healthy controls (HC, n = 35) in a neutral state and after idiosyncratic negative emotion induction while electroencephalography (EEG) was recorded. The EEG data were analyzed using a mass testing approach.

RESULTS

Individuals with AN showed reduced pleasantness for foods compared to objects alongside elevated widespread occipito-central food-object discrimination between 170 and 535 ms, indicative of strong neural cue-reactivity. Food-object discrimination was further increased in the negative emotional condition between 690 and 1200 ms over centroparietal regions. Neither of these effects was seen in individuals with BN.

DISCUSSION

Emotion modulated food-cue-reactivity in AN might reflect a decreased appetitive response in negative mood. Such specific (emotion-)regulatory strategies require more theoretical work and clinical attention. The absence of any marked effects in BN suggests that emotional cue-reactivity might be less prominent in this group or quite specific to certain emotional contexts or food types.

PUBLIC SIGNIFICANCE

Negative affectivity is a risk factor for the development of eating disorders and individuals with eating disorders experience problems with emotion regulation. To better understand the effects of negative emotions, the present study investigated how they affected neural correlates of food perception in anorexia nervosa and bulimia nervosa.

Strategic avoidance of food stimuli in patients with restrictive anorexia nervosa: An eye-tracking evaluation

OBJECTIVE

A biased attentional processing of food stimuli may represent a disorder maintenance factor in patients with anorexia nervosa (AN). The present study aimed at investigating the temporal course of attentional deployment towards both high-calorie and low-calorie foods in patients with AN using eye-tracking.

METHOD

Fifty-two patients with restrictive AN and 54 healthy controls (HC) performed a dot-probe task while their gaze was recorded with an eye-tracking system. The direction bias (percentage of trials in which the gaze was directed towards the food at first fixation, 500, and 1500 ms), and the duration bias (percentage of time spent looking at the food) were extracted.

RESULTS

Regarding the direction bias, a group by time interaction emerged (F = 3.29, p = 0.038): while in the control group the bias continued to increase over the course of the trial, patients with AN showed a reduction of the bias between the 500 and 1500 ms. No group differences were observed on the duration bias.

CONCLUSIONS

In advanced stages of attentional deployment patients with AN start to differ from HC by diverting their attention away from food stimuli, a strategic process that may contribute to food avoidance and calorie restriction.

How much is a chef's touch worth? Affective, emotional and behavioural responses to food images: A multimodal study

BACKGROUND

Food aesthetics influences affective dimensions (valence and arousal) and subsequent emotional and behavioural responses in images presented in more traditional form, almost rustic in some cases, to the signature dishes of haute cuisine. However, the visual impact of images of haute cuisine dishes on consumers' affective and emotional responses compared to traditional dishes is still understudied.

METHODS

We recorded electrodermal activity, ocular movements and self-report affect of 35 volunteers while they performed a picture viewing paradigm using images of haute cuisine food, traditional food, and non-food. Additionally, the moderating role of age was examined.

RESULTS

Our results showed that subjects had higher feelings of pleasure and arousal toward images of food (haute cuisine and traditional dishes) compared to non-food images. However, no difference in self-report affect, physiological and behavioural responses was found between haute cuisine and traditional dishes. Interestingly, a moderating effect of age was revealed, reporting that younger participants had greater feelings of pleasure and shorter eye-to-screen distance towards traditional food than haute cuisine.

CONCLUSIONS

As a whole, our findings suggest that food aesthetics could at least partially affect consumers' affective and emotional responses. Interestingly, physiological responses to food pictures seemed to be relatively independent of approach/avoidance motivational states, supporting the assumption that traditional visual restaurant menus with attractive images might be insufficient for eliciting intense positive emotions. This study also contributes to advancing the understanding of the role that age plays in emotional impact when images of haute cuisine dishes are presented to consumers.

The positive impact of mindfulness interventions on the explicit and implicit affective attitudes toward vegetarian foods

Objectives

The main goal of our intervention study was to investigate whether two conceptually different mindfulness interventions positively impacted the explicit and implicit affective evaluations of vegetarian foods. We included possible mediating variables (e.g., wellbeing) and related our results to the stage model of self-regulated behavioral change (SSBC).

Methods

We implemented a compassion and caring-based mental training (N = 31) and an adapted MBSR course (N = 34) as mindfulness interventions, and a stress-reduction course (N = 26) as the active control group. The curriculums consisted of 12 weekly group sessions á 75 min. All participants were tested pre- and post-intervention and 3 months after the last intervention session, answered questionnaires (mindfulness, compassion, wellbeing, items of the SSBC) and completed an explicit affective evaluation task and an affective priming task.

Results

There was an improvement in the explicit attitudes toward vegetarian foods regardless of the intervention group. In the SSBC, we found a link between the explicit attitudes toward vegetarian foods and the indicated stage in the model. Multiple regression analysis revealed social and personal norms and a vegetarian/vegan diet as the only significant predictors for goal intention in the SSBC.

Conclusion

The results of our study suggest that both conceptually different mindfulness interventions, as well as a stress-reduction program, have a positive impact on explicit affective attitudes toward vegetarian foods. We highlight the meaning of inner dimensions and transformation for change processes for a more sustainable diet and the role of social and personal norms.

Emotional eating: elusive or evident? Integrating laboratory, psychometric and daily life measures

PURPOSE

Emotional eating (EE) refers to eating in response to (negative) emotions. Evidence for the validity of EE is mixed: some meta-analyses find EE only in eating disordered patients, others only in restrained eaters, which suggest that only certain subgroups show EE. Furthermore, EE measures from lab-based assessments, ecological momentary assessment (EMA), and psychometric measures often diverge. This paper tested whether the covariance of these three different EE methods can be modeled through a single latent variable (factorial validity), and if so, how this variable would relate to restrained eating (construct validity), Body-Mass-Index (BMI), and subclinical eating disorder symptomatology (concurrent validity).

METHODS

102 non-eating disordered female participants with a wide BMI range completed EE measures from three methods: psychometric questionnaires, a laboratory experiment (craving ratings of food images in induced neutral vs. negative emotion) and EMA questionnaires (within-participant correlations of momentary negative emotions and momentary food cravings across 9 days). Two measures for each method were extracted and submitted to confirmatory factor analysis.

RESULTS

A one-factor model provided a good fit. The resulting EElat factor correlated positively with subclinical eating disorder symptoms and BMI but not with restrained eating.

CONCLUSIONS

The one-factor solution shows that the EE construct can validly be assessed with three different methods. Individual differences in EE are supported by the data and are related to eating and weight problem symptomatology but not to restrained eating. This supports learning accounts of EE and underscores the relevance of the EE construct to physical and mental health.

LEVEL OF EVIDENCE

II (Evidence obtained from well-designed controlled trials without randomization).

Elevated Insulin Levels Engage the Salience Network during Multisensory Perception

INTRODUCTION

Brain insulin reactivity has been reported in connection with systematic energy metabolism, enhancement in cognition, olfactory sensitivity, and neuroendocrine circuits. High receptor densities exist in regions important for sensory processing. The main aim of the study was to examine whether intranasal insulin would modulate the activity of areas in charge of olfactory-visual integration.

METHODS

As approach, a placebo-controlled double-blind within crossover design was chosen. The experiments were conducted in a research unit of a university hospital. On separate mornings, twenty-six healthy normal-weight males aged between 19 and 31 years received either 40 IU intranasal insulin or placebo vehicle. Subsequently, they underwent 65 min of functional magnetic resonance imaging whilst performing an odor identification task. Functional brain activations of olfactory, visual, and multisensory integration as well as insulin versus placebo were assessed. Regarding the odor identification task, reaction time, accuracy, pleasantness, and intensity measurements were taken to examine the role of integration and treatment. Blood samples were drawn to control for peripheral hormone concentrations.

RESULTS

Intranasal insulin administration during olfactory-visual stimulation revealed strong bilateral engagement of frontoinsular cortices, anterior cingulate, prefrontal cortex, mediodorsal thalamus, striatal, and hippocampal regions (p ≤ 0.001 familywise error [FWE] corrected). In addition, the integration contrast showed increased activity in left intraparietal sulcus, left inferior frontal gyrus, left superior frontal gyrus, and left middle frontal gyrus (p ≤ 0.013 FWE corrected).

CONCLUSIONS

Intranasal insulin application in lean men led to enhanced activation in multisensory olfactory-visual integration sites and salience hubs which indicates stimuli valuation modulation. This effect can serve as a basis for understanding the connection of intracerebral insulin and olfactory-visual processing.

When not responding to food changes food value: The role of timing

Establishing behavior change toward appetitive foods can be crucial to improve people's health. Food go/no-go training (GNG), in which people respond to some food items and not to other food items depending on the presentation of a go or no-go cue, is a means to establish behavior change. GNG changes the perceived value of food items and food consumption. After GNG, no-go items are rated as less attractive than go and/or untrained items, an empirical phenomenon called the NoGo-devaluation-effect. This effect is not always found, however. One theory-based explanation for these inconsistent results may be found in the timing of the go and no-go cues, which is also inconsistent across studies. Hence, in the present work we conducted two experiments to examine the possible role of go and no-go cue presentation timing in eliciting the NoGo-devaluation-effect. In Experiment 1, we presented the food items before the presentation of go/no-go cues, whereas we reversed this order in Experiment 2. As predicted, the NoGo-devaluation-effect was obtained in Experiment 1. This effect was absent in Experiment 2. Moreover, recognition memory for stimulus-action contingencies moderated the devaluation effect in Experiment 1, but not in Experiment 2. These results show that NoGo devaluation is dependent on the timing of the NoGo cue, which has theoretical and applied implications for understanding how and when go/no-go training influences food consumption. We propose that the value of food items is updated during go/no-go training to minimize prediction errors, and that this updating process is boosted by attention.

Attentional bias to food during free and instructed viewing in anorexia nervosa: An eye tracking study

Previous research has shown that patients with anorexia nervosa (AN) show an attentional bias to food. However, due to different conceptualizations of attentional bias and the use of various paradigms, results are inconclusive and more precise insights into the exact nature of this attentional bias are needed. Therefore, an eye-tracking paradigm with food (low and high caloric) and non-food (objects) pictures was used to investigate biases in AN patients (n = 25) compared to healthy controls (n = 22). Several indices of visual attention were examined, both during free (initial orientation, fixation frequency, fixation time) and explicitly instructed (engagement, disengagement) viewing. Our results during the free viewing phase indicated that AN patients (as compared to healthy matched controls) looked less frequently and spent less time fixating on food stimuli, compared to the comparison group. No differences between both groups (n = 47) in initial orientation could be observed. Interestingly, during the instructed viewing phase, no differences between the patient and the comparison group were observed in engagement or disengagement to food stimuli. These results suggest an (initial) attentional avoidance of food in AN patients when closely investigating spontaneous attentional processes, while this could not be observed during gaze behaviour when receiving clear instructions. Hence, future research should look into how attentional bias during spontaneous gaze patterns could serve as a potential marker of AN, and how targeting this bias could be applied in treatment interventions.

The Effect of Response Conditions on Food Images-Evoked Emotions Measured Using the Valence × Arousal Circumplex-Inspired Emotion Questionnaire (CEQ)

In 2020, a single-response-based, valence × arousal circumplex-inspired emotion questionnaire (CEQ) was developed. Using a between-participants design, previous studies have found that a multiple response (MR) condition better discriminated test samples (e.g., written food names) based on their evoked emotions than a single response (SR) condition. This research, comprising Studies 1 and 2, aimed to determine the effect of response conditions (i.e., SR vs. MR) on emotional responses to food image samples, using a within-participants design. In Study 1, 105 Korean participants were asked to select a pair of emotion terms (i.e., SR condition) or select all pairs representing their evoked emotions (i.e., MR condition) from a list of 12 pairs of emotion terms of the CEQ, in response to the 14 food images. Both SR and MR conditions were tested within a remote (online) session. To minimize both a potential carry-over effect of the "within-participants design" and an influence of environmental factors in the remote testing, Study 2 asked 64 U.S. participants to do so over two separated sessions on two different days in a controlled laboratory setting. In both Studies 1 and 2, participants selected the CEQ's emotion-term pairs in the MR condition more frequently than in the SR condition, leading to the MR condition's higher capacity to discriminate test samples. While the configurations of the correspondence analysis biplots drawn in the SR and MR conditions were similar, those in the MR condition were more likely to be similar to the configurations of the principal component analysis biplots drawn from the ratings of valence and arousal for food image samples. In conclusion, this study provides robust empirical evidence that the MR condition can perform better in capturing sample differences in food-evoked emotions, while the SR condition is also effective in characterizing emotional profiles of test samples. Our findings will provide practical insights to sensory professionals, enabling them to effectively leverage the CEQ or its variants when measuring food-evoked emotions.

Exploring the acute effects of running on cerebral blood flow and food cue reactivity in healthy young men using functional magnetic resonance imaging

Acute exercise suppresses appetite and alters food-cue reactivity, but the extent exercise-induced changes in cerebral blood flow (CBF) influences the blood-oxygen-level-dependent (BOLD) signal during appetite-related paradigms is not known. This study examined the impact of acute running on visual food-cue reactivity and explored whether such responses are influenced by CBF variability. In a randomised crossover design, 23 men (mean ± SD: 24 ± 4 years, 22.9 ± 2.1 kg/m² ) completed fMRI scans before and after 60 min of running (68% ± 3% peak oxygen uptake) or rest (control). Five-minute pseudo-continuous arterial spin labelling fMRI scans were conducted for CBF assessment before and at four consecutive repeat acquisitions after exercise/rest. BOLD-fMRI was acquired during a food-cue reactivity task before and 28 min after exercise/rest. Food-cue reactivity analysis was performed with and without CBF adjustment. Subjective appetite ratings were assessed before, during and after exercise/rest. Exercise CBF was higher in grey matter, the posterior insula and in the region of the amygdala/hippocampus, and lower in the medial orbitofrontal cortex and dorsal striatum than control (main effect trial p ≤ .018). No time-by-trial interactions for CBF were identified (p ≥ .087). Exercise induced moderate-to-large reductions in subjective appetite ratings (Cohen's d = 0.53-0.84; p ≤ .024) and increased food-cue reactivity in the paracingulate gyrus, hippocampus, precuneous cortex, frontal pole and posterior cingulate gyrus. Accounting for CBF variability did not markedly alter detection of exercise-induced BOLD signal changes. Acute running evoked overall changes in CBF that were not time dependent and increased food-cue reactivity in regions implicated in attention, anticipation of reward, and episodic memory independent of CBF.

Testing the effectiveness of a mobile approach avoidance intervention and measuring approach biases in an ecological momentary assessment context: study protocol for a randomised-controlled trial

INTRODUCTION

Unhealthy eating behaviour is a major contributor to obesity and related diseases and is associated with a behavioural bias to approach rather than avoid desired foods, as measured with reaction time tasks. Approach-avoidance interventions (AAIs) have been proposed as a way to modify food evaluations and help people to eat in accordance with their dietary goals. Mobile implementations of AAI might be easily accessible, low threshold interventions, but their effectiveness has not been established yet.

METHODS AND ANALYSIS

Participants who aim to change their eating behaviour are randomised to intervention or control groups. They complete six sessions of a smartphone-based AAI, in which they push (ie, avoid) or pull (ie, approach) personalised food images. Intervention group participants always avoid foods that they personally want to eat less often and approach foods that they personally want to eat more often. In the control group, images are paired equally often with both response directions. To evaluate contextual and dynamic intervention effects, ecological momentary assessment (EMA) is measured throughout, with questions about food intake, hunger, stress, emotions, eating intentions, food craving and impulsivity twice a day. Additional EMA preintervention and postintervention measures are administered before and after the intervention phase (4 days each) with a 1-day follow-up EMA 4 weeks after the intervention. Multilevel models will examine the temporal covariance between approach bias and self-reported variables as well as short-term and long-term intervention effects on approach bias, food intake and craving.

ETHICS AND DISSEMINATION

The study was approved by the Ethics Committee of the University of Salzburg. Results will be published in peer-reviewed scientific journals and presented at scientific conferences.

TRIAL REGISTRATION NUMBER

German Clinical Trials Register DRKS, registration number DRKS00030780.

Brain responses to food viewing in women during pregnancy and post partum and their relationship with metabolic health: study protocol for the FOODY Brain Study, a prospective observational study

INTRODUCTION

Food cravings are common in pregnancy and along with emotional eating and eating in the absence of hunger, they are associated with excessive weight gain and adverse effects on metabolic health including gestational diabetes mellitus (GDM). Women with GDM also show poorer mental health, which further can contribute to dysregulated eating behaviour. Food cravings can lead to greater activity in brain centres known to be involved in food 'wanting' and reward valuation as well as emotional eating. They are also related to gestational weight gain. Thus, there is a great need to link implicit brain responses to food with explicit measures of food intake behaviour, especially in the perinatal period. The aim of this study is to investigate the spatiotemporal brain dynamics to visual presentations of food in women during pregnancy and in the post partum, and link these brain responses to the eating behaviour and metabolic health outcomes in women with and without GDM.

METHODS AND ANALYSIS

This prospective observational study will include 20 women with and 20 without GDM, that have valid data for the primary outcomes. Data will be assessed at 24-36 weeks gestational age and at 6 months post partum. The primary outcomes are brain responses to food pictures of varying carbohydrate and fat content during pregnancy and in the post partum using electroencephalography. Secondary outcomes including depressive symptoms, current mood and eating behaviours will be assessed with questionnaires, objective eating behaviours will be measured using Auracle and stress will be measured with heart rate and heart rate variability (Actiheart). Other secondary outcome measures include body composition and glycaemic control parameters.

ETHICS AND DISSEMINATION

The Human Research Ethics Committee of the Canton de Vaud approved the study protocol (2021-01976). Study results will be presented at public and scientific conferences and in peer-reviewed journals.

Measuring food-related inhibition with go/no-go tasks: Critical considerations for experimental design

The use of go/no-go tasks to assess inhibitory control over food stimuli is becoming increasingly popular. However, the wide variability in the design of these tasks makes it difficult to fully leverage their results. The goal of this commentary was to provide researchers with crucial aspects to consider when designing food-related go/no-go experiments. We examined 76 studies that used food-themed go/no-go tasks and extracted characteristics related to participant population, methodology, and analysis. Based on our observations of common issues that can influence study conclusions, we stress the importance for researchers to design an appropriate control condition and match stimuli between experimental conditions in terms of emotional and physical properties. We also emphasize that stimuli should be tailored to the participants under study, whether at the individual or group level. To ensure that the task truly measures inhibitory abilities, researchers should promote the establishment of a prepotent response pattern by presenting more go than no-go trials and by using short trials. Researchers should also pre-specify the criteria used to identify potentially invalid data. While go/no-go tasks represent valuable tools for studying food cognition, researchers should choose task parameters carefully and justify their methodological and analytical decisions in order to ensure the validity of results and promote best practices in food-related inhibition research.

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 < 0.05, FWE-corrected). Palatability and calorie content could be decoded from multi-voxel activity patterns (p < 0.05, 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.

Touchscreen-based approach-avoidance responses to appetitive and threatening stimuli

BACKGROUND AND OBJECTIVES

Individuals are thought to be biased towards approaching positive stimuli and avoiding negative stimuli. Yet, it is unclear whether this general pattern applies to all stimulus classes or whether biases are more specific. We expected significant approach biases towards two types of positive stimuli, appetitive foods and butterflies; and avoidance biases away from two types of negative stimuli, spoiled foods and spiders.

METHODS

A touchscreen-based Approach-Avoidance Task (AAT), using hand gestures toward or away from stimuli assessed biases. Questionnaires and image ratings assessed individual differences in stimulus evaluations.

RESULTS

Approach biases for butterflies and appetitive foods were found, the latter being strongest towards individually liked foods. There was no avoidance bias for spoiled foods. An avoidance bias for spiders was found in individuals with elevated spider fear.

LIMITATIONS

Incomplete counterbalancing precluded direct comparison between both positive and negative stimuli.

CONCLUSIONS

Behavioural biases in the touchscreen AAT generally co-vary with individuals' affective evaluation of the stimuli. Approach biases were elicited by positive stimuli independently of whether they were regularly (foods) or rarely (butterflies) approached in everyday life. This may hint towards a tendency to approach positive stimuli regardless of the specific category, whereas avoidance biases may be more stimulus specific.

ERP and attachment dimensions as predictors of seeking care or food comfort in stressful situations

In this study, we aimed to test the association of the Late Positive Potential (LPP) response and attachment dimensions in the choice of care/food pictures and its reaction time (RT) in threatening versus neutral conditions. Fifty-two participants (38 females, M_age 22.62) responded to the ECR questionnaire and were exposed to adequate visual stimuli, during EEG recording. Results showed that threatening stimuli increase the choice of care, decrease RT, and increase LPP magnitude in centro-parietal areas (Cpz, Pz, P3 and P4). Food choice was lower, with increased RT. Furthermore, larger LPP magnitude in centro-parietal cluster was associated with increased RT in the choice of care. Considering the dimensions of attachment, in threatening conditions, while anxiety was not associated with RT and care/food choice, avoidance was associated with an increase in care choice and RT. In conclusion, the specific association of increased RT in care choice with high LPP magnitude centro-parietal cluster may be explained in terms of a functional interference of these areas in the choice of care, but not of food. Further, we postulate that the increased RT of avoidant individuals may reflect a more articulated choice process.

Do we know our visual preferences?

Humans differ in the amount of time they direct their gaze toward different types of stimuli. Individuals' preferences are known to be reliable and can predict various cognitive and affective processes. However, it remains unclear whether humans are aware of their visual gaze preferences and are able to report it. In this study, across three different tasks and without prior warning, participants were asked to estimate the amount of time they had looked at a certain visual content (e.g., faces or texts) at the end of each experiment. The findings show that people can report accurately their visual gaze preferences. The implications are discussed in the context of visual perception, metacognition, and the development of applied diagnostic tools based on eye tracking.

Visual processing of food stimuli: The impact of working memory load and color

Our environment is surrounded by appetizing food stimuli that contribute to an increase in health problems such as obesity and overweight. Understanding the cognitive factors underlying the processing of food stimuli can play an important role in health interventions. Recent studies showed that high-calorie food stimuli impair working memory (WM) task performance, and some individuals, such as restrained eaters, are more susceptible to this WM performance decrement. The present study investigated the effect of low and high WM load on the processing of food stimuli in restrained and unrestrained eaters. Using an n-back task, identical food (low and high calorie) and non-food (object) stimuli were presented in colored (Experiment 1A) or in grayscale (Experiment 1B) versions. Performance was assessed by reaction time (RT), d-prime, and response bias C variables. Results revealed differences in the different WM load conditions. While no effects were observed in the low load, higher WM load impaired task performance. Processing the food stimuli, compared to objects, led to longer RTs and decreased task performance, indicated by d prime and response bias, only when the stimuli were presented in color but not in grayscale. Though no difference was observed in restrained and unrestrained eaters, the role of WM load on the visual processing of the food stimuli remains to be further examined.

Nutrient scoring for the DEGS1-FFQ - from food intake to nutrient intake

BACKGROUND

While necessary for studying dietary decision-making or public health, estimates of nutrient supply based on self-reported food intake are barely accessible or fully lacking and remain a challenge in human research. In particular, detailed information on dietary fiber is limited. In this study we introduce an automated openly available approach to assess self-reported nutrient intake for research purposes for a popular, validated German food frequency questionnaire (FFQ).

METHODS

To this end, we i) developed and shared a code for assessing nutrients (carbohydrates, fat, protein, sugar, fiber, etc.) for 53 items of the quantitative, validated German DEGS1-FFQ questionnaire implementing expert-guided nutritional values of diverse sources with several raters. In a sample of individuals (n_GUT-BRAIN = 61 (21 female) overweight, omnivorous), we ii) cross-validated nutrient intake of the last 7 days and the last 24 h and iii) computed test-retest reliability across two timepoints. Further, iv) we reported newly computed nutrient intake for two independent cross-sectional cohorts with continuous weight status and different dietary habits (n_Mensa = 134 (79 female, 1 diverse), n_GREADT = 76 male). Exploratively, we v) correlated computed, energy-adjusted nutrient intake with anthropometric markers and HbA1c and vi) used linear mixed models to analyse the predictability of BMI and WHR by nutrient intake.

RESULTS

In overweight adults (n = 61 (21 female), mean age 28.2 ± 6.5 years, BMI 27.4 ± 1.6 kg/m²) nutrient intakes were mostly within recommended reference nutrient ranges for both last 7 days and last 24 h. Recommended fiber intake was not reached and sugar intake was surpassed. Calculated energy intake was significantly higher from last 24 h than from last 7 days but energy-adjusted nutrient intakes did not differ between those timeframes. Reliability of nutrient values between last 7 days and 24 h per visit was moderate (Pearson's rho_all ≥ 0.33, rho_max = 0.62) and absolute agreement across two timepoints was low to high for 7 days (Pearson's rho_min = 0.12, rho_max = 0.64,) and low to moderate for 24 h (Pearson's rho_min = 0.11, rho_max = 0.45). Associations of dietary components to anthropometric markers showed distinct sex differences, with overall higher intake by males compared to females and only females presenting a negative association of BMI with fiber intake. Lastly, in the overweight sample (but not when extending the analysis to a wider BMI range of 18.6-36.4 kg/m²), we could confirm that higher BMI was predicted by lower energy-adjusted fiber intake and higher energy-adjusted fat intake (when adjusting for age, sex and physical activity) while higher WHR was predicted by higher energy intake.

CONCLUSION

We provide an openly available tool to systematically assess nutrient intake, including fiber, based on self-report by a common German FFQ. The computed nutrient scores resembled overall plausible and reliable measures of nutrient intake given the known limitations of FFQs regarding over- or underreporting and suggest valid comparability when adjusting for energy intake. Our open code nutrient scoring can help to examine dietary intake in experimental studies, including dietary fiber, and can be readily adapted to other FFQs. Further validation of computed nutrients with biomarkers and nutrient-specific metabolites in serum, urine or feces will help to interpret self-reported dietary intake.

Differential Orbitofrontal Cortex Responses to Chocolate Images While Performing an Approach-Avoidance Task in the MRI Environment

Background: Chocolate is one of the most frequently craved foods, and it often challenges self-regulation. These cravings may be underpinned by a neural facilitation of approach behavior toward chocolate. This preregistered study investigated the behavioral and neural correlates of such a bias using functional magnetic resonance imaging (fMRI) and reaction times (RTs). Methods: A total of n = 30 frequent chocolate eaters performed a relevant-feature approach-avoidance task (AAT) in the MRI scanner using buttons to enlarge (approach) or to shrink (avoid) pictures of chocolate and inedible control objects. We tested (a) whether implicit RT-based approach biases could be measured in a supine position in the scanner, (b) whether those biases were associated with activity in reward-related brain regions such as the insula, amygdala, striatum, and orbitofrontal cortex (OFC), and (c) whether individual RT-based bias-scores correlated with measures of chocolate craving. Results: Behaviorally, we found a highly reliable approach bias toward chocolate, defined by faster RTs in the compatible conditions (approach chocolate, avoid objects) compared to the incompatible conditions (avoid chocolate, approach objects). Neurally, this compatibility effect involved activity in the left medial OFC, a neural response that was positively correlated with individual approach bias scores. Conclusions: This study shows that the relevant feature AAT can be implemented in an fMRI setting in a supine position using buttons. An approach bias toward chocolate seems related to medial OFC activation that might serve to devalue chocolate when it has to be avoided. Our demonstration of neural and behavioral approach biases for chocolate underscores the need for stimulus-specific cognitive trainings to support healthy consumption and successful self-regulation.

Challenging inhibitory control with high- and low-calorie food: A behavioural and TMS study

Most people are often tempted by their impulses to "indulge" in high-calorie food, even if this behaviour is not consistent with their goal to control weight in the long term and might not be healthy. The outcome of this conflict is strongly dependent on inhibitory control. It has already been reported that individuals with weaker inhibitory control consume more high-calorie food, are more often unsuccessful dieters, overweight or obese compared to people with more effective inhibitory control. In the present study, we aimed at investigating inhibitory control in the context of human eating behaviour. A sample of 20 healthy normal-weight adults performed a 50% probability visual affective Go/NoGo task involving food (high- and low-calorie) and non-food images as stimuli. Single-pulse transcranial magnetic stimulation (TMS) was administered over the right primary motor cortex (M1) either 300 ms after image presentation to measure corticospinal excitability during the different stimulus categories or 300 ms after the appearance of a fixation point, as a control stimulation condition. The experimental session consisted of a food target and a non-food target block. Behavioural outcomes showed a natural implicit inclination towards high-calorie food in that participants were faster and more accurate compared to the other categories. This advantage was selectively deleted by TMS, which slowed down reaction times. MEPs did not differ according to the stimulus category, but, as expected, were bigger for Go compared to NoGo trials. Participants judged high-calorie food also as more appetising than low-calorie food images. Overall, our results point to a differential modulation when targeting inhibitory control, in favour of the more palatable food category (high-calorie). Present data suggest that the activity of the motor system is modulated by food nutritional value, being more engaged by appetising food. Future work should explore to what extent these processes are affected in patients with eating disorders and should aim to better characterise the related dynamics of cortical connectivity within the motor network.

Development of Chinese food picture library for inducing food cravings

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

Adult Avoidant Attachment, Attention Bias, and Emotional Regulation Patterns: An Eye-Tracking Study

Proximity-seeking in distress situations is one of attachment theory's primary strategies; insecure individuals often also develop secondary strategies. The mechanisms implied in attachment deactivation constitute a key issue in the current debate related to their role in support-seeking. The main aim of this study is to investigate the attachment deactivation strategy and the processes of proximity/support-seeking under distress conditions by analyzing the attentional processes (i.e., an essential emotion-regulation strategy), using eye-tracking techniques. Seventy-two participants (45 female; M_age 23.9 ± 3.97) responded to the ECR-R questionnaire in order to identify their attachment style. They participated in an experimental situation in which they had to choose between pictures of care or pictures of food, following the presentation of threatening or neutral prime conditions (via the pictures' stimuli). Results showed that a care-consistency response pattern was the most frequent pattern of response, particularly under a threatening condition; on the contrary, only avoidant individuals showed a lower care-consistency response pattern by choosing food pictures. The overall findings demonstrate that avoidant individuals used the deactivation strategy to process comfort-related attachment pictures, suggesting that they considered these stimuli to be threatening. The implications for attachment theory and particularly for avoidant strategies are discussed.

Food-Induced Brain Activity in Children with Overweight or Obesity versus Normal Weight: An Electroencephalographic Pilot Study

BACKGROUND

Although increased food cue reactivity is evidenced to be crucial to the development and maintenance of pediatric obesity, virtually nothing is known about the underlying neurophysiological aspects of food cue reactivity in children with obesity. Therefore, this study aimed at investigating neural characteristics in children with overweight or obesity using electroencephalography (EEG).

METHODS

Electrophysiological brain activity was measured using EEG frequency band analysis in n = 9 children with overweight or obesity versus n = 16 children with normal weight (8-13 years) during the presentation of high- and low-calorie food pictures and images of appealing non-food stimuli.

RESULTS

Children with overweight or obesity showed significantly increased relative central beta band activity induced by high-calorie foods and appealing non-food stimuli compared to children with normal weight. Beyond significant effects of the scalp region on EEG activity, non-significant effects of stimulus category or weight status were seen for theta and alpha frequency bands.

CONCLUSIONS

This study demonstrated elevated beta band activity in children with overweight or obesity when viewing high-calorie food stimuli. Beta band activity may, thus, be a valuable target for neuromodulatory interventions in children with overweight or obesity.

Impact of obesity and diet on brain structure and function: a gut-brain-body crosstalk

Most societies witness an ever increasing prevalence of both obesity and dementia, a scenario related to often underestimated individual and public health burden. Overnutrition and weight gain have been linked with abnormal functionality of homoeostasis brain networks and changes in higher cognitive functions such as reward evaluation, executive functions and learning and memory. In parallel, evidence has accumulated that modifiable factors such as obesity and diet impact the gut-brain axis and modulate brain health and cognition through various pathways. Using neuroimaging data from epidemiological studies and randomised clinical trials, we aim to shed light on the underlying mechanisms and to determine both determinants and consequences of obesity and diet at the level of human brain structure and function. We analysed multimodal 3T MRI of about 2600 randomly selected adults (47 % female, 18-80 years of age, BMI 18-47 kg/m²) of the LIFE-Adult study, a deeply phenotyped population-based cohort. In addition, brain MRI data of controlled intervention studies on weight loss and healthy diets acquired in lean, overweight and obese participants may help to understand the role of the gut-brain axis in food craving and cognitive ageing. We find that higher BMI and visceral fat accumulation correlate with accelerated brain age, microstructure of the hypothalamus, lower thickness and connectivity in default mode- and reward-related areas, as well as with subtle grey matter atrophy and white matter lesion load in non-demented individuals. Mediation analyses indicated that higher visceral fat affects brain tissue through systemic low-grade inflammation, and that obesity-related regional changes translate into cognitive disadvantages. Considering longitudinal studies, some, but not all data indicate beneficial effects of weight loss and healthy diets such as plant-based nutrients and dietary patterns on brain ageing and cognition. Confounding effects of concurrent changes in other lifestyle factors or false positives might help to explain these findings. Therefore a more holistic intervention approach, along with open science tools such as data and code sharing, in-depth pre-registration and pooling of data could help to overcome these limitations. In addition, as higher BMI relates to increased head micro-movements during MRI, and as head motion in turn systematically induces image artefacts, future studies need to rigorously control for head motion during MRI to enable valid neuroimaging results. In sum, our results support the view that overweight and obesity are intertwined with markers of brain health in the general population, and that weight loss and plant-based diets may help to promote brain plasticity. Meta-analyses and longitudinal cohort studies are underway to further differentiate causation from correlation in obesity- and nutrition-brain research.

Decoding continuous variables from event-related potential (ERP) data with linear support vector regression using the Decision Decoding Toolbox (DDTBOX)

Multivariate classification analysis for event-related potential (ERP) data is a powerful tool for predicting cognitive variables. However, classification is often restricted to categorical variables and under-utilises continuous data, such as response times, response force, or subjective ratings. An alternative approach is support vector regression (SVR), which uses single-trial data to predict continuous variables of interest. In this tutorial-style paper, we demonstrate how SVR is implemented in the Decision Decoding Toolbox (DDTBOX). To illustrate in more detail how results depend on specific toolbox settings and data features, we report results from two simulation studies resembling real EEG data, and one real ERP-data set, in which we predicted continuous variables across a range of analysis parameters. Across all studies, we demonstrate that SVR is effective for analysis windows ranging from 2 to 100 ms, and relatively unaffected by temporal averaging. Prediction is still successful when only a small number of channels encode true information, and the analysis is robust to temporal jittering of the relevant information in the signal. Our results show that SVR as implemented in DDTBOX can reliably predict continuous, more nuanced variables, which may not be well-captured by classification analysis. In sum, we demonstrate that linear SVR is a powerful tool for the investigation of single-trial EEG data in relation to continuous variables, and we provide practical guidance for users.

The Restrain Food Database: validation of an open-source database of foods that should be eaten more or less as part of a healthy diet

Studies of food-related behaviours often involve measuring responses to pictorial stimuli of foods. Creating these can be burdensome, requiring a significant commitment of time, and with sharing of images for future research constrained by legal copyright restrictions. The Restrain Food Database is an open-source database of 626 images of foods that are categorized as those people could eat more or less of as part of a healthy diet. This paper describes the database and details how to navigate it using our purpose-built R Shiny tool and a pre-registered online validation of a sample of images. A total of 2150 participants provided appetitive ratings, perceptions of nutritional content and ratings of image quality for images from the database. We found support for differences between Food Category on appetitive ratings which were also moderated by state hunger ratings. Findings relating to individual differences in appetite ratings as well as differences between BMI weight categories are also reported. Our findings validate the food categorization in the Restrain Food Database and provide descriptive information for individual images within this investigation. This database should ease the burden of selecting and creating appropriate images for future studies.

Consumer Awareness of the Degree of Industrial Food Processing and the Association with Healthiness-A Pilot Study

Consumption of ultraprocessed foods (UPFs) has been associated with lower diet quality, obesity, and adverse health effects. Not much is known about how consumers evaluate the degree of processing of a food product and how they relate this to healthiness. An online questionnaire was completed by a total of 277 Dutch, 204 Italian, and 181 Brazilian consumers. Consumers were aged 18-65 year, mean 38 ± 13 year, 31% were males, and 71% were highly educated. Pictures of several common food products were evaluated on the degree of industrial processing and healthiness. Thirteen food categories were included, each including one minimally processed food (MPF), one High NS_UPF (Nutri-Score A or B), and one Low NS_UPF (Nutri-Score D or E). Lastly, knowledge and attitude about UPFs were assessed. Ultraprocessing was perceived as unhealthy by the majority of consumers (Dutch, Italian: 55%; Brazilian: 75%) and contributed to weight gain according to: 38% Dutch, 51% Italian, and 70% Brazilian consumers. Low NS_UPFs were correctly rated toward "processed" and "not healthy" in all countries. High NS_UPF were rated as processed but showed large variations in healthiness scores. In conclusion, consumers rated UPFs relatively low in healthiness compared with MPFs with similar Nutri-Scores within the same food category. These preliminary findings suggest that consumers incorporate, to some extent, the degree of industrial processing while assessing the healthiness of food products.

Neural responsiveness to Chinese versus Western food images: An functional magnetic resonance imaging study of Chinese young adults

Cross-cultural studies suggest that people typically prefer to eat familiar foods from their own culture rather than foreign foods from other cultures. On this basis, it is plausible that neural responsiveness elicited by palatable food images from one’s own culture differ from those elicited by food depictions from other cultures. Toward clarifying this issue, we examined neural activation and self-report responses to indigenous (Chinese) versus Western food images among young Chinese adults. Participants (33 women, 33 men) viewed Chinese food, Western food and furniture control images during a functional magnetic resonance imaging (fMRI) scan and then rated the images on “liking,” “wanting,” and “difficult resisting.” Analyses indicated there were no significant differences in self-report ratings of Chinese versus Western food images. However, Chinese food images elicited stronger activation in regions linked to cravings, taste perception, attention, reward, and visual processing (i.e., cerebellum crus, superior temporal gyrus, supramarginal gyrus, middle temporal gyrus, inferior parietal lobule, posterior insula, middle occipital gyrus; inferior occipital gyrus). Conversely, Western food images elicited stronger activation in areas involved in visual object recognition and visual processing (inferior temporal gyrus, middle occipital gyrus, calcarine). These findings underscored culture as a potentially important influence on neural responses to visual food cues and raised concerns about the ecological validity of using “standard” Western food images in neuroimaging studies of non-Western samples. Results also provide foundations for designing culturally informed research and intervention approaches in non-Westerns contexts guided by the use of external food cues that are most salient to the cultural group under study.

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.

Responding to Distress Choosing Between Care and Food: Attachment Orientation and Emotion Regulation

According to attachment theory, care-seeking is the primary coping strategy in threatening situations. However, anxious and avoidant individuals often use secondary regulation strategies. The purpose of this study was to test whether, in a potentially threatening situation, the participants' attachment orientation affects whether they prefer to resort to care or food to regulate their negative emotions. Ninety-two participants took part in an experimental situation in which they had to choose between pictures of care or food, following the presentation of threatening images randomly alternating with neutral ones. Results showed that care pictures were chosen to a greater extent in the threatening condition compared to the food pictures and the neutral condition, without distinction of attachment orientation. In addition, in threatening condition, anxious individuals chose to care less than non-anxious individuals. Finally, avoidant participants chose care pictures to a lesser extent than individuals low on avoidance in the neutral condition, but not in the threatening condition. In conclusion, attachment anxiety was associated with more difficulty in the choice of representation of care in a threatening condition, while avoidant individuals show their defensive strategies in the neutral condition rather than in the threatening condition.

A resource for assessing dynamic binary choices in the adult brain using EEG and mouse-tracking

We present a dataset combining high-density Electroencephalography (HD-EEG, 128-channels) and mouse-tracking intended as a resource for examining the dynamic decision process of semantics and preference choices in the human brain. The dataset includes resting-state and task-related (food preference choices and semantic judgments) EEG acquired from 31 individuals (ages: 18–33). Along with the dataset, we also provided the preliminary microstate analysis of resting-state EEG and the ERPs, topomap, and time-frequency maps of the task-related EEG. We believe that the simultaneous mouse-tracking and EEG recording would crack the core components of binary choices and further index the temporal dynamics of decision making and response hesitation. This publicly available dataset could support the development of neural signal processing methods in motor EEG, thus advancing research in both the decision neuroscience and brain-computer interface (BCI) applications.

Measurement(s)	brain measurement (resting/task) • mouse trajectory; binary decision-making
Technology Type(s)	high-density EEG • Experiment

Chinese Food Image Database for Eating and Appetite Studies

Modern people live in an environment with ubiquitous food cues, including food advertisements, videos, and smells. Do these food cues change people’s eating behavior? Since diet plays a crucial role in maintaining health, it has been researched for decades. As convenient alternatives for real food, food images are widely used in diet research. To date, researchers from Germany, Spain, and other countries have established food photo databases; however, these food pictures are not completely suitable for Chinese studies because of the ingredients and characteristics of Chinese food. The main goal of this research is to create a library of Chinese food images and to provide as complete a data reference as possible for future studies that use food images as experimental material. After standardized processing, we selected 508 common Chinese food pictures with high familiarity and recognizability and attached detailed classifications concerning taste, macronutrients, calories, and participants’ emotional responses to the pictures. Additionally, with food pictures as material, we conducted research on how people make dietary decisions in order to identify the variables that may affect a person’s food choices. The effects of individual perceived healthiness and palatability, gender, BMI, family income, and levels of emotional and restricted eating were examined using eating decisions based on healthiness and palatability as dependent variables. The results showed that people with low household incomes are more likely to be influenced by food taste in their dietary decision-making process, while individuals with high household incomes are more likely to consider the healthy aspects of food. Moreover, parental BMI affects what children consume, with children who have parents with higher BMIs being more prone to overlook the healthiness value of food.

Dietary Fiber and WHO Food Categories Extension for the Food-Pics_Extended Database

Well characterized databases used for experimental purposes with extensive meta-data are essential for conducting meaningful and comparable studies. The Food-pics_extended database (Blechert et al., 2019) is one example for a widely used food stimulus database (original publication Blechert et al., 2014: 285 citations, and 2019: 32 citations). Indeed, meta-data on low level and high level image characteristics is broad, yet fiber ratings are not included, limiting its use in diet-related studies. Therefore, we developed fiber ratings per item (n = 562 stimuli), based on mean values of four non-expert raters. Ratings show good reliability (ICC = 0.77) and meaningful ranges per food type (mean fiber per 100 g by food type min_beverages = 0.04 ± 0.04 g and max_{Ready–to–eatsavories} = 4.49 ± 1.58). The newly provided fiber ratings enrich the already valuable database and extend it by an important nutrient value for human and planetary health.