Dynamic changes in the food-cue processing of obese adolescents: A controlled eye-tracking study from a dual-system perspective

An advance in novel intelligent sensory technologies: From an implicit-tracking perspective of food perception

Food sensory evaluation mainly includes explicit and implicit measurement methods. Implicit measures of consumer perception are gaining significant attention in food sensory and consumer science as they provide effective, subconscious, objective analysis. A wide range of advanced technologies are now available for analyzing physiological and psychological responses, including facial analysis technology, neuroimaging technology, autonomic nervous system technology, and behavioral pattern measurement. However, researchers in the food field often lack systematic knowledge of these multidisciplinary technologies and struggle with interpreting their results. In order to bridge this gap, this review systematically describes the principles and highlights the applications in food sensory and consumer science of facial analysis technologies such as eye tracking, facial electromyography, and automatic facial expression analysis, as well as neuroimaging technologies like electroencephalography, magnetoencephalography, functional magnetic resonance imaging, and functional near-infrared spectroscopy. Furthermore, we critically compare and discuss these advanced implicit techniques in the context of food sensory research and then accordingly propose prospects. Ultimately, we conclude that implicit measures should be complemented by traditional explicit measures to capture responses beyond preference. Facial analysis technologies offer a more objective reflection of sensory perception and attitudes toward food, whereas neuroimaging techniques provide valuable insight into the implicit physiological responses during food consumption. To enhance the interpretability and generalizability of implicit measurement results, further sensory studies are needed. Looking ahead, the combination of different methodological techniques in real-life situations holds promise for consumer sensory science in the field of food research.

Food stimuli decrease activation in regions of the prefrontal cortex related to executive function: an fNIRS study

PURPOSE

Overweight/obese individuals show impairments in executive functions such as inhibitory control. However, the neural mechanisms underlying these disturbances-and specifically, whether or not they involve altered activation of the specific prefrontal cortex regions-are not yet fully understood.

METHODS

The motivational dimensional model of affect suggests that high approach-motivated positive affect (e.g., desire) may impair executive function. In the present study, we investigated individual differences in neural responses to videos of food stimuli, and examined brain activity during a cognitive task in an approach-motivated positive state using functional near-infrared spectroscopy (fNIRS). In Experiment 1, in 16 healthy young adults, we tested whether prefrontal cortex activation differed during a food video clip versus a neutral video clip. Then, after viewing each video clip, we tested for differences in executive function performance and prefrontal cortex activation during a Stroop task. Experiment 2 was the same, except that we compared 20 overweight/obese with 20 healthy young adults, and it incorporated only the food video clip.

RESULTS AND CONCLUSIONS

The results of both experiments indicated that food stimuli decrease activation in regions of the prefrontal cortex related to executive function. This study also suggests that overweight/obese might consciously suppress their responses to a desired stimulus, yet here it seems that effect was less pronounced than in healthy controls.

LEVEL OF EVIDENCE

Level II, Cohort Studies.

Effect of body-related information on food attentional bias in women with body weight dissatisfaction

Women with body weight dissatisfaction (BWD) have long-term negative assessments of their body weight, which are often associated with poor eating behavior. In this study, we investigated the effect of body-related information on the food cue processing and attention of women with BWD. Sixty-eight women were recruited and assigned to either a BWD (NPSS-F > 2) (n = 32) or a no body weight dissatisfaction (NBWD) group (NPSS-F < 1) (n = 36). We measured attentional bias to food cues (high- and low-calorie) with a food probe task after exposure to body-related information and recorded eye tracking data. Body-related images were presented prior to a pair of stimulus images (food-neutral or neutral-neutral). Body-related information and food type were repeated measure factors in our study. Our results showed that the first fixation duration bias for high-calorie foods was significantly longer than for low-calorie foods after exposure to overweight cues in the BWD group. Compared with the NBWD group, the BWD group showed longer first fixation duration bias for high-calorie foods after exposure to overweight cues. The direction for high-calorie foods was significantly more often than that for low-calorie foods in the BWD group after exposure to body-related information. Our findings suggest that compared to women with NBWD, women with BWD may be more susceptible to body-related information, resulting in increased attention to high-calorie foods.