Motivational Effects of Hunger on Time Estimation and Delay of Gratification in Obese and Nonobese Boys

Time estimates and ability to delay gratification of obese and nonobese boys were compared by a 2x2x2 factorial experiment in which hunger and edibility of incentives were manipulated. Hunger did not affect estimates of the obese boys, while it significantly shortened estimates made by the nonobese boys when the hunger drive was made either specific or nonspecific by varying incentive conditions. Although estimates of the nonobese boys were significantly shorter in the edible than nonedible incentive condition, edibility of incentives did not affect the estiamtes of the obese, suggesting a general rather than food-specific arousal in the nonobese and a general lack of response to internal cues in the obese. Immediate rewards were chosen significantly more often by obese than nonobese Ss. However, delay gratification in both obese and nonobese was unaffected by the hunger and edibility of incentive manipulations. This was attributed to uncontrolled cognitive variables.