ERPs to stimulus identification in persons with restrained eating behavior.

Restrained eating is an eating behavior in which hunger and satiety are not the only triggers for starting or ending a meal. Rather, cognitive factors control food consumption in these persons. The present study served to investigate cortical stimulus processing in restrained and unrestrained eaters by means of event-related potentials (ERPs). ERPs should differ between these two groups and this difference should vary according to food intake. ERPs were recorded from 20 female restrained and 20 female unrestrained eaters in a word identification task in which food-related and food-unrelated words were repeatedly presented tachistoscopically. Half of the participants of each group were tested after food intake, the other half after food deprivation. Although, there were no differences between the ERPs of food-related and food-unrelated words, ERPs were more positive going in restrained eaters compared with unrestrained eaters. Food intake led to a decrease of the P2-amplitude in restrained eaters while increasing it in unrestrained eaters, regardless of stimulus-type. The results suggest that restrained eaters generally differ in their cortical stimulus processing from unrestrained eaters and that a preload has opponent effects in both groups of participants in the early states of stimulus processing.