How Male and Female detect food-related stimuli? Change detection assessed by a Food Flicker Task

INTRODUCTION In recent years many authors have investigated the attentional bias for food-related stimuli. However, to our knowledge, no study has assessed the change blindness for images of high-calorie and low-calorie food. Alike no study investigated whether males and females presented a different attentional bias for food-related stimuli. The aim of this study was to investigate, in male and female, the change blindness for different type of food-related stimuli versus neutral stimuli, using a particular version of the Flicker Task (Food Flicker Task). METHOD One-hundred fifty-eight students participated in the experiment. According to their gender, the participant were splitted into two groups: Female (N=79; Age:25,03; DS:4,31) and Male (N=79; Age:24,91; DS:3,34). In the Food Flicker Task on each trial, an original and modified version of a picture alternated repeatedly (240-ms display time), separated by a gray screen (80 ms), until the participants pressed the space bar to indicate they had detected the change. The change can be of Marginal (MA) or Central interest (CE). The images, selected from the International Affective Picture System, showed high-calorie (HC) and low-calorie (LC) food, or Neutral stimuli (NEU). RESULTS An ANOVA Group (Females, Males) x Type of Change (CE, MA) x Stimuli (HC, LC, NEU) on Response Time (RT) revealed a significant effect of Group (F1,156=9,79; p=0,002; pη2=0,06), Male are faster then Female; Location (F1,156=508,63; p<0,001; pη2=0,76), CE were identified faster than MA; and Stimuli (F2,312=576,44; p<0,001; pη2=0,78), RT were quicker in Food-related images then in NEU. The Stimuli x Type of Change (F2,312=58,39; p<0,001; pη2=0,27) showed faster RT in CE when the stimuli were HC; while the RT in MA were faster for LC. The analysis of Accuracy confirmed results on RT, excluding the presence of a trade-off effect, but it also evidences a significant interaction between Group and Type of Change(F1,156=6,76; p=0,01; pη2=0,10), revealing that Male were more accurate than Female only in MA (p=0,01). DISCUSSION Many researches investigated food attraction and attentional bias food-related in clinical samples. This study use a non-clinical sample and results revealed that there is an attentional bias for food-related stimuli, regardless of the fact that they are low-calorie foods or high-calorie foods, and this bias is more pronounced in males than in females. These findings emphasize that the Food Flicker Task can be advantageously used to investigate attentional bias in Eating Behaviors.