Development and Evaluation of a Virtual Reality Puzzle Game to Decrease Food Intake: Randomized Controlled Trial.

BACKGROUND: Virtual reality (VR) has gained popularity in daily life, and VR food cues seem to elicit food cravings, similar to real food cues. However, little is known about the impact of VR food cues on actual food intake. OBJECTIVE: In real life (RL), exposure to food cues in a situation in which the desire to eat food interferes with the completion of a food-related task reduces the subsequent food intake (ie, the pre-exposure effect). In this study, we examine, on the one hand, whether the pre-exposure effect could be replicated in RL and, on the other hand, whether this effect could be extended to VR contexts. METHODS: The study used a 2 (stimulus type: food vs nonfood) × 2 (mode: VR vs RL) between-subject design (n=175). Participants were randomly assigned to 1 of the 4 conditions. RESULTS: We found the main effect of mode on food intake, with a higher food intake after both VR conditions than after RL conditions (P=.02). In addition, among female participants, we found that exposure to both food cues (ie, VR and RL) resulted in lower food intake than exposure to both nonfood cues (P=.05). In contrast, this effect was not observed among male participants (P=.34). Additionally, VR and RL cues generated similar emotional and behavioral responses (eg, arousal and game difficulty). CONCLUSIONS: We were unable to replicate the exposure effect in our complete sample. Subgroup analyses, however, showed that for women, exposure to food cues (either in VR or in RL) reduces food intake, indicating that a VR pre-exposure procedure may effectively be applied exclusively for women. TRIAL REGISTRATION: ClinicalTrials.gov NCT05169996; https://clinicaltrials.gov/ct2/show/NCT05169996.

A Multilab Replication of the Ego Depletion Effect.

There is an active debate regarding whether the ego depletion effect is real. A recent preregistered experiment with the Stroop task as the depleting task and the antisaccade task as the outcome task found a medium-level effect size. In the current research, we conducted a preregistered multilab replication of that experiment. Data from 12 labs across the globe (N = 1,775) revealed a small and significant ego depletion effect, d = 0.10. After excluding participants who might have responded randomly during the outcome task, the effect size increased to d = 0.16. By adding an informative, unbiased data point to the literature, our findings contribute to clarifying the existence, size, and generality of ego depletion.

Pre-exposure to Tempting Food Reduces Subsequent Snack Consumption in Healthy-Weight but Not in Obese-Weight Individuals.

Obesity has become a severe worldwide problem. Compared to healthy-weight individuals, obese individuals seem to show an increased sensitivity to tempting food. In the present study, we test the pre-exposure effect, which implies that consumption of tempting food is decreased after exposure to tempting food cues in a context of a task that discourages food consumption. Healthy-weight and obese-weight participants were recruited via social media and university channels. Participants took part in a scrabble task with either candy letters or foam letters and subsequently engaged in a taste test. Results showed that in healthy-weight participants, consumption was reduced after solving the scrabble task with candy letters in comparison to foam letters. In obese-weight participants, consumption was reduced in the condition using foam letters (in comparison with healthy-weight participants). The pre-exposure effect was replicated in healthy-weight participants, but could not be observed in participants with obesity, since consumption was reduced in general in this group. Our results suggest that more work should be done to understand how food nudges work in the context of obesity.