A psychophysical analysis of perceived satiety: Its relation to consumatory behavior and degree of overweight

The psychophysical technique of cross-modal matching was used to scale perceived satiety. In three experiments, a total of 108 subjects matched the changing level of perceived satiety by adjusting the length of a metal tape at 2-min intervals while eating a fixed-amount meal and filling out a questionnaire afterwards. Perceived satiety rose linearly during the meal at a rate of 4% a minute, reaching 40% of maximum satiety in the 6-min meal time. Perceived satiety fell after the meal at a rate of 1% a minute for at least 10 min. Normal weight subjects did not differ from overweight subjects in initial satiety level or in the rate at which satiety changed either during or after the meal. The close tie between perceived satiety and the act of eating points to the importance of consummatory behavior in determining feelings of satiety; the slow fall of satiety after the meal indicates that it is also dependent on internal states that persist after eating. Thus satiety seems to depend both on oropharyngeal cues and on some quickly occurring but relatively long lasting internal changes caused by ingestion. Longer-term changes in satiety following ingestion remain to be assessed.