Instrumental responding following reinforcer devaluation

In two experiments, hungry rats were given instrumental lever-press training for an appetitive reinforcer and, in addition, were exposed to another type of food which was not contingent on lever pressing. In the first experiment, exposure to each type of food was on separate days, whereas in the second experiment rats were exposed to each type of food in strict alternation within each session. Subsequently, a food aversion was conditioned to the reinforcer for the experimental group and to the non-contingent food for the control group. In both experiments, animals with an aversion to the reinforcer responded less in an extinction test than animals with an aversion to the non-contingent food. Subsequent reacquisition tests confirmed that the aversion to the non-contingent food in the control group was of comparable strength with that to the reinforcer in the experimental group. The results were discussed in terms of whether the reinforcer is encoded in the associative structure set up by exposure to an instrumental contingency.     

A quantitative analysis of the relationship between the Cook-Medley Hostility Scale and traditional coronary artery disease risk factors.

One possible explanation for the association between Cook-Medley Hostility Scale (Ho Scale; W. W. Cook & D. M. Medley, 1954) scores and premature coronary artery disease (CAD) morbidity and mortality is that hostile persons also have elevations on CAD risk factors. Meta-analyses with fixed and random-effects models were used to evaluate the relationship between Ho Scale scores and CAD risk factors in the empirical literature. Ho Scale scores were significantly related to body mass index, waist-to-hip ratio, insulin resistance, lipid ratio, triglycerides, glucose, socioeconomic status (SES), alcohol consumption, and smoking. Although there was also heterogeneity among study outcomes, the results of conservative random effects models provide confidence in the obtained relationships. On the basis of available evidence, researchers might give attention to obesity, insulin resistance, damaging health behaviors, and SES as potential contributing factors in understanding the association between Ho Scale scores and CAD.     

Drinking and Driving: Perceptions and Evaluations as a Function of Level of Intoxication and Weather

Over the past decade, drinking and driving has been a major social problem causing deaths and injuries. The present study examined factors that may encourage this potentially self-destructive behavior. Three hundred and seventy-eight subjects were presented with scenarios describing a night of drinking with friends. Scenarios differed with respect to three levels of intoxication (not at all, slight, and very) and two levels of weather (clear and rain). Subjects were asked to estimate the proportion of their peers who would drive home or choose an alternative form of transportation. Subjects were also asked to evaluate the target who drove home or took an alternative in terms of likability, cautiousness, skillfulness and independence. Driving home was found to be the most common mode of transportation, regardless of state of drunkenness or weather conditions. Alternatives to driving home were seen as being utilized only under extreme conditions (e.g., very intoxicated and rainy weather). Moreover, persons taking one of the more cautious alternatives were perceived as overly cautious and also low in skillfulness. The practical implications for the findings are discussed with respect to enhancing education efforts.     

Studies of psychosocial influences on coronary artery atherogenesis in cynomolgus monkeys

The cynomolgus macaque provides a suitable primate model for studying how psychosocial factors contribute to coronary artery atherogenesis. Important interactions with diet, sex, and behaviorally elicited cardiovascular reactivity are described.     

Effects of Perceived Group Effectiveness and Group Role on Attributions of Group Performance1

Cadets at the U.S. Military Academy completed a questionnaire describing their experiences in Cadet Basic Training (CBT) and Cadet Field Training (CFT). Analyses of variance examined the impact of Group Role (Leader vs. Follower) and Perceived Group Effectiveness (High vs. Low) on group member perceptions of the extent to which each of six factors affected group performance. Significant main effects for Perceived Effectiveness were interpreted in terms of the egodefensive bias. Role main effects indicated that leaders tended to make stronger dispositional attributions than did followers. There were no signifcant Group Role × Perceived Effectiveness interaction effects. Findings support, in part, hypotheses concerning the operation of an attributional bias within the leader-member relationship.