Differential attention to food images in sated and deprived subjects.

DOI: 10.5176/2251-1865_CBP13.48

Authors: David N. Velázquez-Martínez, Anna L Toscano-Zapién, Daniel Velázquez-López

Abstract:

When deprived of food, subjects decrease their latency to find a dot that appears after a word or food image compared to the latency to locate the dot after a non-food word or image (Dot Probe Task). We recorded fixation time to relevant areas in the screen (Areas of interest: AOI) and pupil diameter as a more direct evaluation of attention to food stimulus. Participants with a mild food deprivation (4h) were instructed to fixate their gaze at a central point in a screen before being confronted with a pair of images; thereafter they had to match the color of a key with the colored dot that followed one of the images. Images used were stationery items or images of “light”, carbohydrate- or fat-rich content food. Images were presented in pairs of all possible combination-location and the time to fixation, the pupil diameter and the duration of each gaze at each image presented were recorded. No differences were observed in the fixation times or when the two stimuli presented belonged to the same stimulus category. When one stimulus was an image of an office item or “light” food and the other stimulus was dessert or high-fat food, subjects preferred to gaze at the dessert or high-fat food. Results confirm preferential attention to food images of carbohydrate- or fat-rich food than to office items or “light” food when subjects are food motivated by a deprivation period of 4h but not when 1h of food deprivation.

Keywords: Differential attention, food intake, saccadic eye movement.