Food-Related Attentional Bias in Individuals with Normal Weight and Overweight: A Study with a Flicker Task

The primary purpose of the present study was to investigate attentional biases for food-related stimuli in individuals with overweight and normal weight using a flicker paradigm. Specifically, it was tested whether attention allocation processes differ between individuals with overweight and normal weight using transient changes of food-related and neutral pictures. Change detection latencies in objects of central interest (CI) or objects of marginal interest (MI) were measured as an index of attention allocation in a sample of fifty-three students with overweight/obesity and sixty students with normal weight during a flicker paradigm with neutral, hypercaloric and hypocaloric food pictures. Both groups of participants showed an attentional bias for food-related pictures as compared to neutral pictures. However, the bias was larger in individuals with overweight than in individuals with normal weight when changes were of marginal interest, suggesting a stronger avoidance of the food-related picture. This study showed that food-related stimuli influence attention allocation processes in both participants with overweight and normal weight. In particular, as compared to individuals with normal weight, those with overweight seem to be characterised by a stronger attentional avoidance of (or smaller attention maintenance on) food-related stimuli that could be considered as a voluntary strategy to resist food consumption.

Seeing through the Eyes of Others: Social Interaction Perception in Normal and Schizophrenia Subjects

What cognitive processes specify understanding of humans’ behavior in communicative situations? 51 healthy controls and 50 schizophrenia patients were presented with social “silent” video clips and then they performed flicker task and predicted characters’ behavior. During the experiment eye movements were recorded. Observers, who have made successful predictions, evaluated the characters’ actions, specified how they categorized the objects and events, and then profiled the objects’ features, on which just these categorizations were based. Information about these features remained in working memory and directed a communicative situation’s perception. Observers noticed the events, relevant to the viewpoints of the characters, and understood their gazes, gestures and actions. Those, who have made unsuccessful predictions, advanced hypotheses about how the characters categorized the objects and events, but they did not profile the objects’ features, on which categorizations were based. They demonstrated “blindness” to the events, relevant to the viewpoints of the characters, and did not understand a coherence of their actions.