Use of an operant task to estimate food reinforcement in adult humans with and without BED.
OBJECTIVE
The purpose of this study was to demonstrate the utility of food-reinforced operant task performance in modeling binge-eating disorder (BED). We hypothesized that food reinforcement after a caloric preload would be related to BED status, but not hunger.


METHODS
We investigated the association between reports of hunger, binge tendency, and food reinforcement in a sample of 18 women (12 non-BED, 7 lean, 5 obese, and 6 obese BED). Participants completed two sessions of operant task performance after consuming 600 ml of flavored water or 600 ml of a 1 kcal/ml liquid meal.


RESULTS
Under the water condition, food reinforcement did not differ between the non-BED and BED groups, and was positively correlated with hunger ratings across all participants (r = 0.55, P = 0.023). Under the liquid meal condition, food reinforcement was significantly decreased compared with the water condition in the non-BED group (t = -2.6, P = 0.026). There was also a significant difference between the non-BED and BED groups in the fed condition (41 +/- 40, 117 +/- 60, F = 10.3, P = 0.005, non-BED vs. BED, respectively, mean +/- s.d.). The correlation between food reinforcement and hunger remained significant only in the non-BED group (r = 0.69, P = 0.011).


CONCLUSIONS
Our results support the hypothesis that food reinforcement measured after a caloric preload is related to BED status but not hunger in those subjects with BED. The data also suggest that operant task performance can be useful in modeling BED criteria such as "eating when not physically hungry."
Nasser
Jennifer A
JA
New York Obesity Research Center, St Luke's-Roosevelt Hospital Center, Columbia University, New York, New York, USA. jnasser@att.net
Evans
Suzette M
SM
Geliebter
Allan
A
Pi-Sunyer
F Xavier
FX
Foltin
Richard W
RW
D000328:Adult; D052018:Bulimia Nervosa / Q000523:psychology*; D003216:Conditioning, Operant; D005247:Feeding Behavior / Q000523:psychology*; D005260:Female; D006801:Humans; D006815:Hunger; D008875:Middle Aged; D012054:Reinforcement, Psychology; D013647:Task Performance and Analysis