A 2007 study by the University at Buffalo showed that overweight children habituate to food more slowly than those of a normal weight. In this study, children were allowed to "earn" 100 calorie portions of a cheeseburger or fries by pressing buttons on a computer. They were told that at any time, if they no longer wanted to work towards a food reward, they could go to another table and play age-appropriate games. Obese children stayed to earn more calories than children who were of normal weight...unless the food stimulus was french fries, in which case the results were about the same.
Habituation to food stimuli is clearly a critical part of the process when it comes to our food choices. Much of the purpose of marketing and advertising is to reduce our ability to habituate by presenting the product in ways that engage us. I'll be curious to see if the Carnegie-Mellon continues this line of research, and publishes a dietary version of Professor Harold Hill's musical Think System.