Incentive properties of sucrose and saccharin under different deprivation conditions

In Expt 1 it was found that hungry rats developed a 100% preference for 8% sucrose over water in a maze-choice situation, whereas thirsty rats developed no preference. When deprivation conditions for the two groups were reversed the pattern of preference relations also reversed. In a 2nd experiment nondeprived rats developed a preference for either 8% sucrose or 0.2% saccharin over water while thirsty Ss did not develop a preference for either of these over water. The results are discussed in terms of incentive theory.     

Analysis of activity preferences as a function of differential consequences

Individuals who do not possess the verbal skills to express meaningful choice in the absence of its consequences may have difficulty indicating their preference for protracted activities that are unavailable until some time in the future (e.g., taking a walk, riding a bike). When we examined the preferences of 4 individuals with developmental disabilities by showing them pictorial representations of various activities, their initial choices showed no clear preferences. In a subsequent condition, selecting a photograph resulted in brief access to the depicted activity. When selections produced differential consequences (i.e., access to the activity), clear preferences emerged. In addition, 3 individuals' preferences were later shifted to an initially less preferred but more socially desirable option by superimposing additional reinforcement contingencies for engaging in the less preferred activity. Results are discussed in terms of the conditions under which choice functions as an indicator of preference and how those conditions may be altered to improve the quality of choice making without limiting access to preferred options.     

Autoshaping as a function of prior food presentations

Young chickens were given 1, 10, 100, or 1000 presentations of grain in a hopper. Subsequently, the key was illuminated before each presentation of grain to study autoshaping of the key-peck response. The number of keylight-grain pairings before a bird first pecked the lighted key was found to be a U-shaped function of the number of prior food-only presentations, with pecks occurring significantly sooner after 100 food-only trials than after any of the other values. Two of five chicks at the 100-trial value pecked on the first illumination of the key. Experiment II showed further that when a series of food-only trials (no keylight) preceded keylight-only trials (no food) 30% of the chicks pecked the illuminated key. Experiment III extended the generality of first-trial pecking to pigeons. After preliminary training with food-only, two of five pigeons pecked on the first illumination of a key. The results suggest a close relationship between autoshaping and pseudo-conditioning.     

Changing food preference as a function of mood

The authors investigated the effect of mood on food selection. Participants (N = 98) indicated the likelihood of general eating and the likelihood of eating specific foods after reading and projecting themselves onto the events and emotions described in a sad and a happy vignette. Both men and women believed they were more likely to consume food following a happy versus a sad event, and men believed they were significantly more likely to eat than did women. However, the type of food men and women believed they would consume interacted with the type of event experienced. Vegetarian snack foods were more likely to be consumed following a happy versus a sad event, with men more likely to eat snack foods. Men did not significantly change in likelihood of consuming sweet foods as their mood changed. However, women believed they were more likely to consume sweet foods following a sad event. The authors discuss the results in terms of a self-medication hypothesis and the effect of carbohydrates on central serotonin and endogenous opioids. Overall, results demonstrated that mood influences belief in the likelihood of food selection.     

Response to cigarette deprivation as a function of oral fantasy.

The role of oral fantasy in reactions of heavy smokers to smoking deprivation was studied. Experimental subjects were first evaluated with the Holtzman Inkblot Test to measure amount of oral fantasy. They also evaluated themselves on a number of Semantic Differential continua. Smoking deprivation followed. Retest Holtzman blots and Semantic Differential rating scales were then administered. Subjects also indicated number of somatic symptoms and body image distortions produced by deprivation. Control subjects followed the same paradigm except they smoked throughout the procedure. It was found that the greater the orality of experimental subjects the greater the number of somatic symptoms and body distortions they experienced following deprivation; and the more they viewed self as having shifted in a less favorable and less potent direction. Such relationships were absent in the control group.     

Experimental analysis of preschool playmate preferences as a function of smiles and sex

Differential emotions theory (DET) (The face of emotion. Appleton‐Century‐Crofts: East Norwalk, CT, 1971) posits that the smile functions in part to communicate and/or reflect social affiliation and plays an important role in children's social development. While children's positive emotion expressions have received attention from peer relations researchers in observational studies and within correlational designs, there is almost no experimental evidence for the impact of the smile. Building on existing studies, the present study examined DET predictions within an experimental design. More specifically, we examined the impact smiles have on lower‐income preschool children's nominations for preferred playmates. Both boys and girls tended to nominate unfamiliar playmates who smiled. Additionally, some evidence suggested that preference for smiling playmates seemed more critical to girls' than boys' social functioning. Unlike among boys, teachers rated girls who exhibited a greater preference for smiling playmates as higher in social competence. Copyright © 2008 John Wiley & Sons, Ltd.     

Potency of food deprivation intensity cues as discriminative stimuli.

Rats were trained to use stimuli arising from 0 and 24 hr without food as discriminative signals for shock. In Experiment 1, one group was shocked under 0-hr food deprivation and not shocked under 24-hr food deprivation. Another group received the reverse contingency. The groups received only 3 training trials under each deprivation level. Learning was revealed in a test phase when greater extinction of freezing was observed under the nonshocked than under the shocked deprivation level for both groups. A similar pattern of results was obtained in Experiment 2 when auditory cues were also relevant throughout training. Furthermore, prior training with food deprivation cues seemed to reduce learning about auditory cues subsequently trained in compound with deprivation stimuli. The results indicate that food deprivation intensity cues can be potent discriminative stimuli. The idea that deprivation cues function as conditioned modulatory stimuli cues is also discussed.