Temporal pattern of agonist-antagonist EMG activity during rapid limb movements in man

Analysis of elbow-extension movements, executed at maximal velocity, show positive correlations of timing of agonist-antagonist EMG activity with both movement velocity and displacement. Results indirectly support the notion that the antagonist musculature provides a braking force to arrest rapid limb movements.     

Book Reviews

The Psychological Record -     

Book Notes

The Psychological Record -     

In search of the false-uniqueness phenomenon: fear and estimates of social consensus

An examination of the social perception literature yields little evidence for the false-uniqueness phenomenon (Valins & Nisbett, 1972), the perception that one's attributes are more unique than is the case. In contrast, the tendency for individuals to project their own characteristics onto other people and assume that more people are like themselves is a robust phenomenon. One reason researchers may not have found false uniqueness is that they have not looked at the accuracy of consensus estimates. A close look at the results of Tabachnik, Crocker, and Alloy (1983) and Sanders and Mullen (1983), who did assess accuracy, suggests that people possessing undesirable attributes over-estimate consensus, whereas people holding desirable attributes underestimate consensus. The latter pattern is a form of false uniqueness. In this study we looked at the accuracy of social consensus estimates in the context of psychological fears. A sample of subjects filled out an abbreviated version of a fear survey and made estimates of consensus. The results showed that both high- and low-fear respondents overestimated the incidence of high fear among their peers, but high-fear subjects were more inaccurate in their estimates. A false-uniqueness effect was found on the part of low-fear subjects, as they tended to underestimate the incidence of low fear among their peers. These findings are consistent with a motivational interpretation that emphasizes the individual's need to justify or normalize stigmatized behavior and to bolster perceived self-competence.     

A conditional approach to dispositional constructs: the local predictability of social behavior

A conditional approach to dispositions is developed in which dispositional constructs are viewed as clusters of if-then propositions. These propositions summarize contingencies between categories of conditions and categories of behavior rather than generalized response tendencies. A fundamental unit for investigating dispositions is therefore the conditional frequency of acts that are central to a given behavior category in circumscribed situations, not the overall frequency of behaviors. In an empirical application of the model, we examine how people's dispositional judgments are linked to extensive observations of targets' behavior in a range of natural social situations. We identify categories of these social situations in which targets' behavior may be best predicted from observers' dispositional judgements, focusing on the domains of aggression and withdrawal. One such category consists of subjectively demanding or stressful situations that tax people's performance competencies. As expected, children judged to be aggressive or withdrawn were variable across situations in dispositionally relevant behaviors, but they diverged into relatively predictable aggressive and withdrawn actions in situations that required the social, self-regulatory, and cognitive competencies they lacked. Implications of the conditional approach for personality assessment and person perception research are considered.     

Social support versus companionship: effects on life stress, loneliness, and evaluations by others

In recent years, much interest has focused on delineating and contrasting specific functions of social relationships that contribute to psychological well-being. Five studies contrasted the roles of companionship and social support in buffering the effects of life stress, in influencing feelings of loneliness and social satisfaction, and in affecting others' judgments. Study 1 analyzed data from a community survey and found that companionship had a main effect on psychological well-being and a buffering effect on minor life stress, whereas social support had only a buffering effect on major life stress. Studies 2, 3, and 4 analyzed data from two college student samples and a different community survey to evaluate how companionship and social support contributed to relationship satisfaction and feelings of loneliness. The results of these studies indicated that companionship was the strongest predictor of these dimensions of social satisfaction. Study 5 used an experimental design to test the hypothesis that a deficit of companionship elicits more negative reactions from others than does a deficit of social support. This hypothesis received partial support. Considered together, the results of these studies suggest that companionship plays a more important and more varied role in sustaining emotional well-being than previous studies have acknowledged.     

Seeking medical care for a breast cancer symptom: determinants of intentions to engage in prompt or delay behavior

This study examined the cognitive structures underlying women's intentions to delay or not delay seeking medical care for a breast cancer symptom. Middle-aged women imagined that they had just discovered a particular change in their breast, and they completed a questionnaire that assessed variables specified by Ajzen and Fishbein's theory of reasoned action with respect to two alternative courses of action: immediately calling the doctor (i.e., prompt behavior) and monitoring the breast change on one's own (i.e., delay behavior). Also assessed were variables external to the theory that were drawn from previous research on cancer delay. Results showed that intentions to delay were positively associated with having favorable attitudes toward delay and with perceived social pressure to delay; the attitudinal factor, however, was more influential than the social factor in determining intentions. Underlying favorable attitudes toward delay were beliefs that delay would be likely to result in maintaining control over and avoiding the disruption of one's own and others' lives but would be unlikely to result in negative health outcomes. No external variable was found to contribute to intentions to delay above and beyond attitudinal and normative considerations.     

Prevalence of weight reducing and weight gaining in adolescent girls and boys

This is a survey of the prevalence of weight reducing and weight gaining in high school children. Our sample of 1,373 high school girls and boys was geographically, racially, and economically diverse. On the day of the survey, 63% of the girls and 16.2% of the boys reported being on weight reducing regimens; 9.1% of the girls and 28.4% of the boys were trying to gain weight. Most female reducers and male gainers were already normal weight. Compared to other racial groups, whites and Hispanics were more likely to be reducing, whereas blacks were more likely to be gaining. Exercise and moderate caloric reduction were most popular for weight reducing, and a small but significant number were regularly using fasting, vomiting, laxatives, and appetite suppressants. The direction of weight modification for girls and boys conformed to stereotyped physical ideals. The rate of weight reducing in female high school adolescents has increased significantly since similar surveys of American youths 20 years ago.