Neural Correlates of Attentional Bias to Food Stimuli in Obese Adolescents

You eye what you eat: BMI, consumption patterns, and dieting status predict temporal attentional bias to food-associated images

People know that overconsumption of high-fat high-sugar (HFHS) foods have negative consequences for physical and cognitive wellbeing but continue to consume these foods in excess, leading to recent proposals to model obesity as an addiction disorder. The current experiment tested, in a large undergraduate sample (N = 306), the hypothesis that obesity and overconsumption is linked with an oversensitivity to rewards that drives attentional biases towards foods and food-associated cues. Using a modified emotion-induced blindness task with food-related distractors, we examined the extent to which attentional biases to images of HFHS foods were accounted for by BMI, HFHS food intake, self-reported hunger, time since last meal, diet status, food preferences, and attentional control. We also examined whether the same individual differences predicted attentional priority to cues that have a learned association with HFHS foods (i.e., images of food logos). Contrary to our predictions, higher BMI predicted less attentional priority for images of food and food logos. At the same time, increased consumption of HFHS foods predicted increased attentional priority for food images, whereas dieting predicted increased attentional priority for food logo images. Our results suggest that different people may preferentially attend to food versus food logo imagery based on their relationships with food. More broadly, our results support the theoretical perspective that attentional biases to food-associated stimuli can be affected by various competing, state-related factors.

Event-related potentials of food-induced blindness in the rapid serial visual presentation paradigm

Emotion-induced blindness is known as the impairment in the identification of targets that follow shortly after emotional distractors in the rapid serial visual presentation (RSVP) paradigm. Besides negative or erotic stimuli, food distractors have also been found to elicit a similar effect. This indicates an attentional bias for food stimuli in the temporal dimension of visual attention, which is highly relevant in the context of eating behaviour. So far, the neural mechanisms of this food-induced blindness are widely unknown. In the present study (N = 53), we investigated event-related potentials (ERPs) in response to food distractors and non-food targets in a single-target RSVP task. Automatic capture of visual attention by task-irrelevant food distractors was evident in enhanced Distractor Negativity (N2) and Early Food Positivity (P1). However, food distractors did not elicit a P3b. Thus, apparently, not the encoding of food distractors in working memory but alternative attentional processes are responsible for the food-induced blindness. Reduced target P3b reflected errors in target identification but was unaffected by the preceding distractor. In contrast, target N2 was specifically reduced for unidentified targets preceded by food distractors. Presumably, the attentional capture of food distractors may have caused a reduction of target N2, thereby contributing to the impairment in target identification. However, future research is needed to confirm this assumption and bridge the gap between the food-induced blindness on the behavioural level and the attentional capture of food stimuli reflected in the distractor ERPs.

High-Calorie Food-Cues Impair Conflict Control: EEG Evidence from a Food-Related Stroop Task

Long-term excessive intake of high-calorie foods might lead to cognitive impairments and overweight or obesity. The current study aimed to examine the effects of high-calorie foods on the behavioral and neurological correlates of food-related conflict control ability. A food-related Stroop task, which asked the participants to respond to the food images and ignore the calorie information, were employed. A total of 61 individuals were recruited and who completed the food-related Stroop task with event-related potentials (ERPs). Participants exhibited a slower reaction time and lower accuracy in high-calorie food stimuli than that in low-calorie food stimuli. The ERP results exhibited a reduction in N2 amplitudes when responding to high-calorie food stimuli compared to when responding to low-calorie food stimuli. In addition, time-frequency analysis revealed that theta power induced by low-calorie food stimuli was significantly greater than that of high-calorie food stimuli. The findings indicated that high-calorie foods impair food-related conflict control. The present study expands on the previous studies of the neural correlates of food cues and provides new insights into the processing and resolving of conflicting information for eating behavior and weight control.

Auditory and cross-modal attentional bias toward positive natural sounds: Behavioral and ERP evidence

Recently, researchers have expanded the investigation into attentional biases toward positive stimuli; however, few studies have examined attentional biases toward positive auditory information. In three experiments, the present study employed an emotional spatial cueing task using emotional sounds as cues and auditory stimuli (Experiment 1) or visual stimuli (Experiment 2 and Experiment 3) as targets to explore whether auditory or visual spatial attention could be modulated by positive auditory cues. Experiment 3 also examined the temporal dynamics of cross-modal auditory bias toward positive natural sounds using event-related potentials (ERPs). The behavioral results of the three experiments consistently demonstrated that response times to targets were faster after positive auditory cues than they were after neutral auditory cues in the valid condition, indicating that healthy participants showed a selective auditory attentional bias (Experiment 1) and cross-modal attentional bias (Experiment 2 and Experiment 3) toward positive natural sounds. The results of Experiment 3 showed that N1 amplitudes were more negative after positive sounds than they were after neutral sounds, which further provided electrophysiological evidence that positive auditory information enhances attention at early stages in healthy adults. The results of the experiments performed in the present study suggest that humans exhibit an attentional bias toward positive natural sounds.