WHAT CAUSES HUMANS TO BEGIN AND END A MEAL - A ROLE FOR MEMORY FOR WHAT HAS BEEN EATEN, AS EVIDENCED BY A STUDY OF MULTIPLE MEAL EATING IN AMNESIC PATIENTS

Although many factors have been proposed and studied as causes of onse t and termination of meals by humans, little attention has been paid t o memory for what has previously been eaten. We propose that a princip al determinant of meal onset and cessation in humans is memory of when a last meal,was eaten and how much,vas consumed. Knowledge that one h as just eaten a culturally defined complete meal may be sufficient gro unds for refusal of further food. This hypothesis was tested by studyi ng two densely amnesic patients who had almost no explicit memory for events that occurred more than a minute ago, and who, in particular us ually failed to remember that they had just eaten a meal. Both patient s (on three occasions each) readily consumed a second lunch when it wa s offered IO to 30 min after completion of the first meal, and usually began to consume a third meal when it,vas offered IO to 30 min after completion of the second meal. These findings suggest that memory for, that has recently been eaten is a substantial contributor to the onset or cessation of eating of a meal.