In Vivo Hippocampal Acetylcholine Release During Exposure to Acute Stress

Hippocampal extracellular acetylcholine (ACh) and choline levels were evaluated using in vivo microdialysis in male Fischer 344 rats before, during, and following an 80-min exposure to two different stress conditions. Measurements were taken in rats restrained and immersed in a water bath containing either 37 degreesC (normothermic-restraint) or 20 degreesC (cold-restraint) water. Results were compared to normothermic-freely-moving rats. Cold-restrained rats displayed decreased ACh levels during cold exposure relative to both normothermic-restrained and normothermic-freely-moving rats. By the end of the cold exposure period and following removal from cold, ACh levels had returned to near-baseline values. Normothermic-restrained rats had levels similar to those of normothermic-freely-moving rats, except for a marked increase in ACh following removal from restraint. Cold-restrained rats displayed a gradual elevation in choline levels during cold stress, followed by a gradual decline after stress termination, whereas both normothermic-restrained and normothermic-freely-moving rats displayed gradual decreases during the microdialysis session. These findings demonstrate that central cholinergic neurotransmission can be altered by the application of, and removal from, acute stressors. In addition, the results suggest a possible relationship between the magnitudes of both the stressor and its cholinergic consequences.     

Social Comparisons and Absenteeism: A Structural Modeling Approach1

In this study a social comparison model is constructed that predicts objectively recorded absence frequency among male Dutch blue-collar workers from a metal factory in the Netherlands. By employing LISREL, the model is developed (tested and revised) in Plant North (N = 254), and successfully cross-validated in Plant South (N= 199). The study demonstrates the impact of two social comparison processes upon absenteeism. Absenteeism is the result of: (a) the perception that one is less well-off than one's colleagues on several job aspects, and (b) the adjustment of one's personal absence norm to that of the work group. In addition, our study reveals that, rather than being absent or having tolerant absence norms, employees may develop feelings of resentment in response to perceived inequity and a tolerant group absence norm. It is concluded that social comparison theory enhances our understanding of absenteeism.     

The effect of social comparison information on the life satisfaction of frail older persons

In this study, the authors examined the effects of social comparison on the life satisfaction of 455 community-dwelling older persons. These older persons were confronted with a fictitious interview with either an upward or a downward target. After downward comparison, older persons felt more satisfied with their lives than after upward comparison, especially those who had higher levels of frailty. These effects were only found with lower levels of identification. Apparently, downward comparison only serves its self-enhancing function on life satisfaction among frail older persons when they perceive the comparison target as different from themselves.     

Neuroticism and social comparison orientation as moderators of affective responses to social comparison at work

In a study among 72 nurses, the affective consequences of social comparison were examined and related to neuroticism (N) and to social comparison orientation (SCO). Participants were confronted with a bogus interview with an upward versus a downward comparison target. Positive affect and identification were higher, and negative affect was lower, in the upward than in the downward comparison condition. Independent of their SCO, the higher individuals were in N, the less they identified with the upward comparison target, the more they identified with the downward comparison target, and the less positive affect they showed following confrontation with the upward comparison target. In contrast, independent of their level of N, the higher individuals were in SCO, the more negative affect they showed following confrontation with the downward comparison target. The effects on negative affect stayed the same when controlling for positive affect, and the effects on positive affect stayed the same when controlling for negative affect. These effects were also obtained when perceived direction was used as a predictor instead of the experimentally manipulated direction. It is concluded that, although N and SCO are correlated, these variables seem to have independent and distinct effects upon the responses to social comparison information.     

The Double-Edged Sword of Providing Information About the Prevalence of Safer Sex1

A group of 267 college students participated in an experiment to determine the effect of communicating different percentages (i.e., 12%, 36%, 64%, 88%) of the prevalence of safer sex in the student population on condom-use intention. A positive linear effect of prevalence information on condom-use intention was demonstrated, although the information that 64% engaged in safer sex seemed most effective in changing condom-use intention. This effect was independent of previous sexual behavior. Although prevalence information had a positive indirect effect on condom-use intention as a result of a change in perceived social norms, it had a negative indirect effect because of perceived risk. That is, information indicating a high prevalence of safer sex lowered the perceived risk of AIDS and, as a result, the intention to use condoms.     

The long‐term effect of social comparison on academic performance

The present study was part of a large‐scale cohort study among several thousand students in the Netherlands. The purpose of the study was to investigate the long‐term effects of comparison choice, i.e., comparison with a target performing better or worse than oneself, and academic comparative evaluation, i.e., the extent to which one thinks one's performance is better or worse than that of others, on scores on standardized tests for reading comprehension and mathematics. While controlling for earlier performance, the results showed that both comparison choice and academic comparative evaluation positively predicted test scores over a period of 2 years. Moreover, it was found that the positive effect of comparison choice only applied to students with a favorable comparative evaluation. Copyright © 2009 John Wiley & Sons, Ltd.     

Social comparison,coping and depression in people with spinal cord injury

The present study among 70 people with spinal cord injury examined the prevalence and correlates of identification (seeing others as a potential future) and contrast (seeing others in competitive terms) in social comparison as related to coping and depression. The most prevalent social comparison strategy was downward contrast (a positive response to seeing others who were worse-off), followed by upward identification (a positive response to perceiving better-off others as a potential future), downward identification (a negative response to perceiving worse-off others as a potential future), and upward contrast (a negative response to seeing others who were better-off). Those with less severe lesions reported the highest levels of upward contrast, coping through blaming others, and depression. Downward contrast was particularly related to constructive coping, and upward identification to wishful thinking. The less adaptive social comparison strategies, i.e., upward contrast and downward identification, were quite strongly related to wishful thinking and blaming others. Particularly upward contrast, i.e., feeling bad as response to seeing that others are better-off, was related to depression.     

The impact of information about the prevalence of AIDS-Preventive behavior among men and women: The mediating role of social norms

Abstract

The present study was designed to examine the effect of information about the high prevalence of safe sex on condom use intention, and to investigate the possible mediating role of the perceived social norm of friends, and the perceived social norm of future. sexual partners. Participants were provided with gender specific prevalence information, that is with the information that most men have exclusively safe sex, or with the information that most women exclusively engage in safe sexual behavior. The results show some gender differences. Information about the high prevalence of safe sex among men tends to increase women's condom use intention, and this effect seems to be mediated by the paceived social norm of future sexual partners. Men's intention, on the other hand, seems to be unaffected by high prevalence information of safe sex. Implications for research and prevention are discussed