Varieties of groups and the perception of group entitativity.

Three studies examined perceptions of the entitativity of groups. In Study 1 (U.S.) and Study 2 (Poland), participants rated a sample of 40 groups on 8 properties of groups (e.g., size, duration, group member similarity) and perceived entitativity. Participants also completed a sorting task in which they sorted the groups according to their subjective perceptions of group similarity. Correlational and regression analyses were used to determine the group properties most strongly related to entitativity. Clustering and multidimensional scaling analyses in both studies identified 4 general types of groups (intimacy groups, task groups, social categories, and loose associations). In Study 3, participants rated the properties of groups to which they personally belonged. Study 3 replicated the results of Studies 1 and 2 and demonstrated that participants most strongly valued membership in groups that were perceived as high in entitativity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Target entitativity: Implications for information processing about individual and group targets.

It is hypothesized that perceptions of entitativity (i.e., seeing social targets as possessing unity and coherence) have important implications for how one organizes information about, and forms impressions of, individual and group targets. When perceivers expect entitativity, they should form an integrated impression of the target, resulting in on-line judgments. However, when perceivers expect little entitativity, they should not process target-relevant information in an integrative fashion, resulting in memory-based judgments. Although many factors affect perceptions of entitativity, the current study focused on expectations of similarity and behavioral consistency. It was predicted that in general, perceivers expect greater entitativity for individual than group targets. However, when explicitly provided with similar expectancies of entitativity, information processing would be similar for both individual and group targets. Two experiments supported these predictions, using recall, memory-judgment correlation, and illusory correlation measures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Quality of group judgment.

Examined the quality of group judgment in situations in which groups have to express an opinion in quantitative form. To provide a measure for evaluating the quality of group performance (which is defined as the absolute value of the discrepancy between the judgment and the true value), 4 baseline models are considered. These models provide a standard for evaluating how well groups perform. The 4 models are: (a) randomly picking a single individual; (b) weighting the judgments of the individual group members equally (the group mean); (c) weighting the 'best' group member (i.e., the one closest to the true value) totally where the best is known, a priori , with certainty; (d) weighting the best member totally where there is a given probability of misidentifying the best and getting the 2nd, 3rd, etc, best member. These 4 models are examined under varying conditions of group size and "bias." Bias is defined as the degree to which the expectation of the population of individual judgments does not equal the true value (i.e., there is systematic bias in individual judgments). A method is then developed to evaluate the accuracy of group judgment in terms of the 4 models. The method uses a Bayesian approach by estimating the probability that the accuracy of actual group judgment could have come from distributions generated by the 4 models. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Perceived entitativity, stereotype formation, and the interchangeability of group members.

The authors investigated the effects of perceived entitativity of a group on the processing of behavioral information about individual group members and the extent to which such information was transferred to other group members. The results of 3 experiments using a savings-in-relearning paradigm showed that trait inferences about a group member, based on that member's behavior, were stronger for low entitative groups and for collections of individuals. However, the transference of traits from 1 group member to other members of the group was stronger for high entitative groups. These results provide strong evidence that the perception of high entitativity involves the abstraction of a stereotype of the group and the transfer of that stereotype across all group members. Implications for group impression formation and stereotyping are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Associations between physical activity and susceptibility to cancer: possible mechanisms

Physical activity is associated with a reduced risk of all-cause and colonic cancers, and it seems to exert a weaker effect on the risk of breast, lung and reproductive tract tumours. This review examines possible mechanisms behind the observed associations. Restriction of physical activity by pre-existing disease may contribute to the association with lung cancers, but seems a less likely explanation for other types of tumour. Indirect associations through activity-related differences in body build or susceptibility to trauma seem of minor importance. Potential dietary influences include overall energy balance and energy expenditure, the intake and/or bioavailability of minerals, antioxidant vitamins and fibre, and the relative proportions of protein and fat ingested. Links between regular exercise and other facets of lifestyle that influence cancer risks are not very strong, although endurance athletes are not usually smokers, and regular leisure activity is associated with a high socioeconomic status which tends to reduce exposure to airborne carcinogens, both at work and at home. Overall susceptibility to cancer shows a 'U'-shaped relationship to body mass index (mass/height2) reflecting, in part, the adverse influences of cigarette smoking and a tall body build for those with low body mass indices and, in part, the adverse effect of obesity at the opposite end of the body mass index distribution. Obesity seems a major component in the exercise-cancer relationship, with a particular influence on reproductive tract tumours; it alters the pathways of estradiol metabolism, decreases estradiol binding and facilitates the synthesis of estrogens. Among the hormonal influences on cancer risk, insulin-like growth factors promote tumour development and exercise-mediated increases in cortisol and prostaglandin levels may depress cellular components of immune function. However, the most important change is probably the suppression of the gonadotropic axis. Apparent gender differences in the benefits associated with regular exercise reflect gender differences in the hormonal milieu and also a failure to adapt activity questionnaires to traditional patterns of physical activity in females. The immune system is active at various stages of tumour initiation, growth and metastasis. However, acute and chronic changes in immune response induced by moderate exercise are rather small, and their practical importance remains debatable. At present, the oncologist is confronted by a plethora of interesting hypotheses, and further research is needed to decide which are of practical importance.     

The Nutrition Attitude Survey: Associations with dietary habits, psychological and physical well-being, and coronary risk factors.

Developed a nutrition attitude survey (NAS) to measure attitudes pertaining to the adoption of a low-fat, low-cholesterol diet. Factor analysis identified 4 primary attitudinal factors: (a) Helpless and Unhealthy, (b) Food Exploration, (c) Meat Preference, and (d) Health Consciousness. For a community sample of 357 healthy men and women, relationships were examined among these attitudinal factors and dietary habits, family food patterns, medical and psychological symptoms (as assessed by the Cornell Medical Index and SCL-90—Revised), and traditional coronary risk factors. Findings provide initial support for the reliability and predictive validity of the NAS and underscore the importance of addressing the attitudes and preferences of participants in dietary intervention programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Person perception and the bounded rationality of social judgment.

In this article, we develop a bounded rationality view of the relation between person perception and social behavior. Two theses of this approach are that behaviors vary in their significance to observers, and that observers pursue bounded rather than global utility in forming personality impressions. Observers are expected to be sensitive to targets' overall behavioral tendencies and to the variability of their behavior across situations, but both sensitivities are bounded, being greater for behaviors that directly affect observers' outcomes. In two investigations involving extensive hourly and 6-s observations, we examined the bounded utility of people's impressions of personality, demonstrating how impression accuracy is linked to the significance of behaviors. Observers were sensitive to the organization of aggressive behaviors, but less sensitive to the organization of withdrawn behaviors, even when the consistency of those behaviors was comparable. The results clarify the relation between people's inferential shortcomings in laboratory paradigms and the bounded utility of person perception in the natural environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stereotypes and social judgment: The consequences of group variability.

The present investigation examined the effects of group variability on judgments of single group members. Male and female participants formed impressions of a group of 50 men or women on the basis of their performance on a test of perceptual-motor skills. The variability of group performance varied across conditions. Participants then made speeded typicality judgments and ability ratings of several "new" group members whose performance varied in its discrepancy from the group. Compared with participants in the high variability condition, participants in the low variability condition were (a) more likely to judge discrepant group members as atypical and (b) faster to assess their atypicality. This latter effect decreased the probability that participants in the low variability condition used the group as a basis for judging atypical group members. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Social categorization and perceptual judgment of size: When perception is social.

Social knowledge may affect not only people's thoughts and judgments but also their actual perceptions of physical magnitude. The physical magnitude of a stimulus is perceived in a relative way, comparing the magnitude of the target surrounding context stimuli. Because similar objects invite comparison processes more easily than dissimilar objects ("similarity breeds comparability"), social knowledge can affect judgments of physical magnitude by determining what is perceived as (dis) similar. In Experiment 1, the authors show that social categorizations that are based on physical cues (e. g., gender) may affect the magnitude of perceptual contrast effects (the Ebbinghaus illusion). More important, in Experiment 2, the influence of social categorizations that have no physical bases is shown to affect the magnitude of perceptual contrast effects. Implications of these findings for theories of social knowledge effects are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differences between caregivers and noncaregivers in psychological health and physical health: A meta-analysis.

Providing care for a frail older adult has been described as a stressful experience that may erode psychological well-being and physical health of caregivers. In this meta-analysis, the authors integrated findings from 84 articles on differences between caregivers and noncaregivers in perceived stress, depression, general subjective well-being, physical health, and self-efficacy. The largest differences were found with regard to depression (g = .58), stress (g = .55), self-efficacy (g = .54), and general subjective well-being (g = -.40). Differences in the levels of physical health in favor of noncaregivers were statistically significant, but small (g = .18). However, larger differences were found between dementia caregivers and noncaregivers than between heterogeneous samples of caregivers, and noncaregivers. Differences were also influenced by the quality of the study, relationship of caregiver to the care recipient, gender, and mean age of caregivers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Projection in group counseling: The relationship between members' interpersonal problems and their perception of the group leader.

Explored projection in group counseling by examining the relationship between the group members' interpersonal problems and their perception of the group leader. Before participation, 118 personal-growth group members filled out the Inventory of Interpersonal Problems by L. M. Horowitz et al (see record 1989-10599-001) and after each session they filled out the Trainer Behavior Scale (L. Bolman, 1971). A latent variable analysis revealed that during the 1st 10 group sessions, overly dominant group members perceived the group leaders as more dominant and overly cold group members perceived the group leaders as less affiliative. There was less relationship between group members' interpersonal problems and ratings for group leaders over time. Implications of these results are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Predicting judgment time from measures of psychological proximity.

Pathfinder networks are evaluated in terms of their ability to predict Ss' response time in category and size judgment tasks. For both tasks, pairwise proximities derived from the network representation of relatedness estimates predicted response times independently of the original relatedness estimates. These results indicate that Pathfinder proximities represent psychological proximity as measured by judgment time better than Ss' own estimates of relatedness. Pathfinder's predictive ability is derived from a focus on relatedness estimates from the more sensitive related end of the rating scale. Evidence supporting this account is presented, and an explanation for sensitivity differences among ratings is proposed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Computer simulation and psychological theories of perception.

Computer simulations of perceptual processes have often not related directly to questions of concern to the psychology of perception and, in particular, have regarded perception as a sensory, as opposed to a sensorimotor or active, process. Some of the psychological literature which is relevant to the issue of perception as a passive vs. an active process is reviewed and differences between these alternative conceptions of perception and gains to be derived from using the active-perceiver model are spelled out. Past computer models are reviewed in the light of such theories. A different simulation program based explicitly on the active-perceiver model of perception is then sketched in broad outlines and its potential for doing research upon psychological problems is reviewed. (50 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Links between physical fitness and cardiovascular reactivity and recovery to psychological stressors: A meta-analysis.

A meta-analysis of published studies with adult human participants was conducted to evaluate whether physical fitness attenuates cardiovascular reactivity and improves recovery from acute psychological stressors. Thirty-three studies met selection criteria; 18 were included in recovery analyses. Effect sizes and moderator influences were calculated by using meta-analysis software. A fixed effects model was fit initially; however, between-studies heterogeneity could not be explained even after inclusion of moderators. Therefore, to account for residual heterogeneity, a random effects model was estimated. Under this model, fit individuals showed significantly attenuated heart rate and systolic blood pressure reactivity and a trend toward attenuated diastolic blood pressure reactivity. Fit individuals also showed faster heart rate recovery, but there were no significant differences in systolic blood pressure or diastolic blood pressure recovery. No significant moderators emerged. Results have important implications for elucidating mechanisms underlying effects of fitness on cardiovascular disease and suggest that fitness may be an important confound in studies of stress reactivity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dependence on external influence: Correlates in perception, attitudes, and judgment.

The hypothesis that people have a generalized tendency to accept or reject external influence is tested in perceptual and conformity situations, using 53 college males as S's. The results show that S's who are highly influenced by the field in one perceptual test perform similarly in other perceptual tests, conformity measures are not significantly interrelated, and field dependent perceptual behavior is associated with high conformity in other tests, particularly autokinetic and attitude change measures. It is suggested that while perceptual performance reflects central tendencies of the person, his performance in specific conformity situations is subject to greater fluctuation as a result of more peripheral factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stereotypes and social judgment: The effects of typicality and group heterogeneity.

Two experiments showed that when subjects believed a group to be heterogeneous, they based their liking for a particular group member on their liking for the group as a whole, independently of and in addition to the target's behavior, and regardless of the target's typicality. When they believed the group to be homogeneous, however, they treated the target's typicality as a favorable or unfavorable attribute, which affected their evaluation. The latter subjects used their group stereotype as a standard of comparison in judging the implications of the target's behavior for a trait to which it was relevant. All subjects' stereotypes had a positive influence on judgments of stereotype-related traits for which the target's behavior was uninformative. A conceptualization is proposed to account for these findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Symptom perception in children with asthma: Cognitive and psychological factors.

Objective: This study tested the differential effects of several cognitive and psychological variables on children's perception of asthma symptoms by use of an Asthma Risk Grid. Children's subjective and objective assessments of PEFR (peak expiratory flow rate) were characterized as representing perceptual accuracy, symptom magnification, and/or underestimation of asthma symptoms. Design: The study included 270 children with asthma (ages 7–17) and their primary caregivers who completed measures assessing cognitive and psychological factors and a 5 to 6 week symptom perception assessment. Main Outcome Measures: Children's symptom perception scores by use of the Asthma Risk Grid. Results: Children's attentional abilities had more of a bearing on their symptom monitoring abilities than their IQ estimates and psychological symptoms. The more time children took on Trails and Cancellation Tasks and the fewer errors they made on these tasks, the more likely they were to perceive their asthma symptoms accurately. More time on these tasks was associated with more symptom magnification scores, and fewer errors were related to fewer symptom magnification scores. More errors and higher total scores on the Continuous Performance Task were associated with a greater proportion of scores in the danger zone. Conclusion: Statistical support was provided for the utility of attentional-based instruments for identifying children who may have problems with perceptual accuracy, and who are at risk for asthma morbidity. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cancer patients psychological adjustment and perception of illness: cultural differences between Belgium and Turkey

Little is known about cultural differences in psychological adjustment and perception of illness (PI) during medical procedures in general and radiotherapy in particular. This study compares a Turkish (TP) and a French speaking Belgian (BP) population. A group of 296 consecutive patients attending the radiotherapy clinic of Institut Jules Bordet, Brussels, (n = 172) and Oncology Institute, Capa-Istanbul, (n = 124) were interviewed and assessed by a symptom checklist, the SCL-90-R, at the beginning and at the end of the radiotherapy. PI, derived from a semi-structured interview, was assessed at the beginning of radiotherapy by a five-point observer-rating scale derived from the Omega Vulnerability Rating Scale. Differences in SCL-90-R scores, taking into account country, age, gender, level of education and PI as potential explanatory variables, have been tested by a multivariate analysis of variance with a design of repeated measures using the SCL-90-R scores as dependent variables. Mainly a time effect and a country effect have been found. Some interactions between both effects have also been found. Globally, all the SCL-90-R scores decrease between the beginning and the end of the radiotherapy. The effect of country is noticeable for most of the SCL-90-R components, with higher scores in the BP, except for the positive symptom total score where the TP showed higher scores. The interaction between country and time is not significant, the scores of both the BP and TP decreasing over time, except for somatization scores (P < 0.001) where the scores of the BP were stable over time while the scores of the TP decreased considerably, and for paranoid ideation scores (P = 0.001) where the scores of the BP decreased while the scores of the TP increased. Results showed a higher rate of correct perception in the BP compared to the TP (P = 0.0001). A PI effect has been found for somatization (P = 0.02), anxiety (P = 0.01) and Global Severity Index scores (P = 0.05), with higher mean scores for the correct perception category. No interaction with time was found. A significant interaction effect between country and PI has been found for anxiety scores with higher scores in the correct perception category in the BP and in the denial of implications category in the TP (P < 0.001). Results highlight cultural differences in psychological adjustment and/or in the responses to self-report questionnaires: greater weight was given to items by the BP, more numerous items were scored by the TP, and greater weight was given to the somatization subscale compared to the psychological subscales by the TP. This study suggests that psychosocial distress is expressed differently in Belgium and Turkey, where patients express mostly somatic complaints. Finally PI, a culture-dependent factor, appears to influence psychological adjustment very differently, a correct perception of illness leading to more anxiety in the BP compared to the TP.