| dc.description.abstract | The purpose of this investigation was to determine the empirical relationships among percentage body weight loss, circulating free fatty acids ( FFA) , and consummatory behavior. A brief review of the literature concerning the relative merits of percentage body weight loss and duration of deprivation as antecedent deprivation conditions was presented. Percentage of body weight loss was concluded to be the empirical.ly superior measure. After a brief review of the literature concerning metabolic measures, circulating FFA concentration was chosen as the metabolic index of deprivation conditions to be investigated in this study. The investigation consisted of two experiments each a factorial design including two levels of percentage body weight loss (10 or 20%) , and four levels of teat duration (0, 30, 60, or 90 minutes). In addition two 0% body weight loss (ad lib.) groups served as controls for FFA concentrations. The blood from one control group was subjected to FFA analysis after a meal was consumed, and the blood from another control group analyzed prior to consumption of a meal. FFA measures from the experimental groups were taken at the end of 0, 30, 60, or 90 minutes of post-deprivation food consumption in Experiment I, and after 0, 30, 60, or 90 minutes of bar pressing on a two minute variable interval reinforcement schedule in Experiment II. In Experiment I, FFA concentrations were found to increase with food deprivation. Neither FFA concentrations nor food consumption were found to differ significantly as a function of percentage body weight loss (10 or 20%). Both FFA concentrations and food consumption were found to decrease as a function of increased test duration. In Experiment II, both FFA concentration and rate of bar pressing were found to differ significantly ae a function of percentage body weight loss (10 or 20%). FFA concentrations were found to decrease as a function of increased test duration, but did not decrease to as low a level as found in Experiment I. It was tentatively concluded that food consumption decreased FFA concentrations due to increased lipogenesis, while bar pressing decreased FFA concentrations due to increased FFA utilization. It was also concluded that although FFA concentrations appear to be correlated with satiation, FFA concentrations alone are not adequate as a metabolic index of deprivation conditions. Suggestions were made for further parametric investigations in which rate of FFA mobilization, amount of body fat, and blood glucose are measured, in addition to circulating FFA. | |
