Objective: Determine the influence of experience with consistent or inconsistent relationships between the sensory properties of snack foods and their caloric consequences on the control of food intake or body weight in rats. Design: Rats received plain and BBQ flavored potato chips as a dietary supplement, along with ad lib rat chow. For some rats the potato chips were a consistent source of high fat and high calories (regular potato chips). For other rats, the chips provided high fat and high calories on some occasions (regular potato chips) and provided no digestible fat and fewer calories at other times (light potato chips manufactured with a fat substitute). Thus, animals in the first group were given experiences that the sensory properties of potato chips were strong predictors of high calories, while animals in the second group were given experiences that the sensory properties of potato chips were not predictors of high calories. Subjects: Juvenile and adult male Sprague-Dawley rats. Measurements: Following exposure to varying potato chip-calorie contingencies, intake of a novel, high-fat snack food and subsequent chow intake were assessed. Body weight gain and body composition as measured by DEXA were also measured. Results: In juvenile animals, exposure to a consistent relationship between potato chips and calories resulted in reduced chow intake, both when no chips were provided and following consumption of a novel high-fat, high-calorie snack chip. Long-term experience with these contingencies did not affect body weight gain or body composition in juveniles. In adult rats, exposure to an inconsistent relationship between potato chips and calories resulted in increased consumption of a novel high-fat, highcalorie snack chip premeal along with impaired compensation for the calories contained in the premeal. Conclusion: Consumption of foods in which the sensory properties are poor predictors of caloric consequences may alter subsequent food intake.

This article presents student and faculty ratings of electronic editing (EE) functions (i.e., track changes, insert comments, highlighting) as used for e-feedback on written assignments. Students reported increased convenience, clarity of expectations, amount of feedback, and writing ability as well as substantial improvement in EE skills compared to paper-based methods. Also, ratings and use of e-feedback were positively correlated with final report grades. To further explore the role of e-feedback in psychology education, a survey indicated that faculty rated e-feedback as similar to paper-based methods for time and effort but potentially more beneficial for learning. In addition, faculty with more e-feedback experience reported higher educational value for EE skills. Advantages and disadvantages from the student and instructor perspectives are discussed.

Adult male rats have been demonstrated to increase food intake in response to administration of drugs that interfere with oxidation of fatty acids (e.g. methyl palmoxirate and mercaptoacetate [MA]), effects that are larger in animals maintained on a high-fat diet. In contrast, while administration of MA has been reported to stimulate food intake in pre-pubertal female rats, food intake is not stimulated by MA in adult female rats. Instead, administration of MA to adult females results in changes in reproductive behavior and physiology. The present experiments were designed to examine the effects of administration of MA on food intake in adult female rats. The results demonstrated that, as previously reported, food intake was stimulated by MA in adult male rats on low-fat and high-fat diets, but food intake was not stimulated by MA in gonadally-intact adult female rats on either low-fat or high-fat diet. Further, MA did not stimulate food intake in female rats ovariectomized as adults. However, when females were ovariectomized prior to the onset of puberty (postnatal day 25-28), food intake was stimulated by administration of MA in adulthood. Finally, cyclic injections of 17-beta-estradiol benzoate given to females ovariectomized prior to the onset of puberty abolished the stimulatory effects of MA on food intake in adult females. Taken together, the data suggest that exposure to estrogens during the time of puberty in female rats can persistently alter adult ingestive responding to signals related to changes in energy utilization.

The present study examined the effects of dietary manipulation on the age of onset of weaning in rat pups. In Experiment 1, female rats were placed on a standard chow (SC) or high-fat (HF) diet 1 week following mating. Pups were weighed daily from birth to Day 12, then animals were placed into specialized cages for separate recording of food intake of pups and dams. Pups were offered the same diet as their dam, and food intake and body weight were determined twice daily until Day 25. The results demonstrated that pups reared by dams fed the HF diet initiated independent ingestion on Day 16, approximately 24 hr before pups reared by dams fed the SC diet. There were no differences in body weight in pups across the two diets. While few differences were noted across diets in pups' or dams' behavior, HF pups appeared to demonstrate a delay in the establishment of circadian patterns of food intake. In Experiment 2, all dams were maintained on an SC diet until the day after parturition. At that time, dams and litters were placed into specialized cages and divided into four groups: HF/HF, HF/SC, SC/SC, and SC/HF (dam's diet/pup's diet, respectively). The results demonstrated that dams given the HF diet had pups that initiated food intake approximately 2 days before the pups of dams given the SC diet. In addition, pups offered the HF diet, independent of the dam's diet, initiated food intake approximately 0.8 days prior to pups offered the SC diet. Further, by Day 12, HF dams had pups that were heavier than SC dams. The results suggest that the onset of weaning in rats is affected by maternal diet and the weaning diet available to the pup.

In adult rats, the rate of gastric emptying is modulated by properties of the diet, including its caloric content and osmotic properties. In developing pups, there is little known about the modulation of gastric emptying, despite evidence that volume of gastric contents may play a significant role in modulating intake in young rats. The present experiments examined gastric emptying of oral infusions of corn oil emulsions or glucose solutions in pups aged 6 or 15 days of age and their effects on independent ingestion. The results demonstrated that pups as young as 6 days of age modulate the rate of gastric emptying in response to changes in the concentration of a corn oil or glucose diet. However, oral infusions of corn oil emulsions failed to produce differences in subsequent intake of a milk diet, while oral infusions of a glucose diet did suppress subsequent intake. Taken together, the results support different ontogenetic courses for the development of mechanisms modulating gastric emptying of lipid versus carbohydrate diets, and suggest that gastric fill plays a limited role in modulation of intake in young pups.