Unraveling Neurophysiological Attentional Habituation Dynamics of Food and Non-Food Paradigms: ERP Correlates with BMI in Response to Repetitive Visual Stimuli

Previous research indicates that human salivary responses habituate to repeated exposure to visual, olfactory, or gustatory food cues in adults and children. This study aims to delve into the neurophysiological dynamics of within-session attentional habituation and its correlation with Body Mass Index (BMI) concerning the repetition of high and low-calorie food, as well as non-food images. Event-related potentials (ERPs) were measured for both high and low BMI groups, as they repeatedly viewed the same food and non-food images. Analysis of ERPs on trial groups within each session revealed distinct effects of repeated image exposure on the brain’s attentional responses to food and non-food stimuli for both BMI groups. The result indicates that habituation effects and significance were observed in the parietal area of the brain for both BMI groups. Specifically, ERP responses to non-food image declined in motivation and attention over time, with significant changes observed within the 170-310 ms and 180-320 ms onset time windows for low and high BMI groups, respectively. However, no significant habituation effect was observed for both low/high caloric images in either BMI group. Additionally, ERP results indicated that high-calorie images exhibited a slower habituation rate, followed by low-calorie and non-food images across both BMI groups. In conclusion, this ERP study revealed that a habituation-like mechanism modulates attention towards repeated non-food images, while food images had a negligible effect in both groups. This suggests that the enhanced reward value associated with high-energy foods might lead to prolonged attention and diminished habituation, potentially contributing to obesity risks in individuals across different BMI groups.