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91.
Abstract

Measures of attitude concerning exposure to the sun, and judgements of risk and other beliefs concerning skin cancer and four other problems (stomach cancer, deafness, AIDS and sunstroke) were obtained from a questionnaire completed by 176 university students. Subjects also estimated the incidence of each problem using one of three response formats. The highest incidence estimates were obtained when subjects were asked to guess at an absolute number, and the lowest when they used a scale which differentiated between lower frequencies, while grouping higher frequencies into a single response category. The effect of the response scale format, however, did not generalize to other ratings of personal risk. Subjects' ratings of their personal risk, compared with their peers, showed an optimistic bias over the five problems as a whole, particularly for AIDS, but not reliably so in the case of skin cancer. Optimism was inversely related to the amount of thought given to each problem. Men and women did not differ overall in their optimism regarding their own risk of skin cancer. However, differences as a function of gender and optimism were found on various behavioural attitudes. The results are discussed in relation to a tendency of disregard base-rates in subjective risk judgements, unrealistic optimism, and implications for health education.  相似文献   
92.
The present study explored the influence of dispositional perfectionism (i.e. perfectionistic concerns and perfectionistic strivings) on tension and performance under low or high experimentally induced stress. Results support the moderating role of perfectionism concerning tension and indicate that stress-related processes underlie the vulnerability of perfectionistic concerns. In addition, buffering effects of perfectionistic strivings were found, supporting the 2 × 2 model of dispositional perfectionism by Gaudreau and Thompson (2010). No evidence was found for the moderating role of perfectionistic strivings concerning performance, but results provide evidence for positive effects of perfectionistic concerns on performance.  相似文献   
93.
In this article we examine whether the distribution of function across the right and left cerebral hemispheres for lexical processing is influenced by the global context within which words are presented. A review of previously published studies indicates that the ubiquitous right visual field (RVF)/left hemisphere advantage for word recognition may be reduced or eliminated for nouns, content words, or high image words, but only when such items are presented along with verbs, function words, or low image words. However, paradoxically, when the former items are presented in more homogeneous contexts, the RVF advantage is uniformly observed. We propose that the processing efficiency of a hemisphere for a given stimulus depends on that item's relation to the other stimuli provided, that is, the global context. This was examined in a visual half-field experiment that varied whether high and low image nouns were presented in homogeneous (blocked lists) or heterogeneous (mixed lists) contexts. An unvarying RVF advantage was observed for high image words in homogeneous contexts, but this advantage was eliminated when the same items were presented in heterogeneous contexts. We suggest that stimulus heterogeneity maximizes reliance on differing, but complementary, computational biases across hemispheres. Hence, the extent to which the left and right hemispheres are recruited for the recognition of individual word types can vary dynamically with variation in the stimulus environment.  相似文献   
94.
Three studies examined how people maintain their self-images when they face threat to interpersonal aspects of the self. In Studies 1 and 2, we found evidence that low self-esteem people lower their estimates of their performance when they expect immediate feedback in order to protect themselves from the interpersonal threat inherent in such feedback, and that self-affirmation reduces this tendency among low self-esteem people. In Study 3, we found that when people are self-affirmed they are more likely to engage in upward social comparisons and less likely to engage in downward social comparisons. Together these findings suggest that people can cope with threats to interpersonal aspects of the self by affirming other important aspects of the self.  相似文献   
95.
The current study examined the contributions of maternal and peer support to depressive symptoms in early to mid-adolescence and variation in these contributions across age, gender, and race. Five waves of data on maternal support, peer support, and depressive symptoms were collected on rural youth (N = 3,444) at 6 month intervals. Multilevel modeling was used to evaluate within and between-person effects of maternal and peer support on depressive symptoms. Within-person effects of peer support did not vary by age, gender, or race. At the between-person level, peer support predicted levels of depressive symptoms at age 12, but this effect became nonsignificant after controlling for maternal support. Within-person effects of maternal support did not vary with age but were qualified by gender and race. Between-person effects of maternal support on depressive symptom levels at age 12 and slopes varied across race and gender, respectively. Findings highlight the robustness of the protective effects of maternal and peer support during adolescence among girls and white youth.  相似文献   
96.

Aim

This study examined whether the predictors of self-reported aggressive driving perpetration and victimization vary across age groups.

Method

Based on data from a general-population telephone survey conducted from July 2002 through June 2005, three groups of drivers were examined: 18–34 year-olds (N = 1522), 35–54 year-olds (N = 2726), and 55 years of age or older (N = 1883). For each age group sample, logistic regression analyses examined self-reported aggressive driving perpetration and victimization in the last 12 months by measures of driving exposure, heavy drinking, cannabis use, and drinking-driving, while controlling for demographic factors.

Results

The prevalence of aggressive driving perpetration within the past year was highest for the youngest age group (51%), followed by the middle-aged group (37%), and then the oldest age group (18%). The same pattern of results was found for prevalence of aggressive driving victimization (54%, 47%, and 31%, respectively). Controlling for demographic factors, the predictors of perpetration were generally consistent across the age groups. The logistic regression model for the youngest drivers revealed that those who reported stressful driving, heavy drinking, and cannabis use had significantly increased odds of reporting perpetration of aggressive driving. For middle-aged and older drivers, stressful driving, driving on busy roads, cannabis use, and driving after drinking were associated with perpetration. In addition, increased mileage contributed to perpetration in the oldest group. The findings for victimization by aggressive driving were similar. The logistic regression model for the youngest age group identified stressful driving, cannabis use, and higher annual mileage as being associated with victimization. For the oldest age group, these same variables were significant predictors of victimization, in addition to driving on busy roads. The logistic regression for the middle-aged group identified the same predictors as that of the oldest age group; however, interestingly driving after drinking was found to predict lower victimization among middle-aged drivers.

Conclusions

Although the prevalence of aggressive driving perpetration and victimization declined with age, the factors that contributed to aggressive driving remained generally stable across the lifespan. The results suggest that efforts to reduce aggressive driving among young drivers may prove to be effective for drivers from all age groups.  相似文献   
97.
Voltage-gated potassium channels (Kv) are critically involved in learning and memory processes. It is not known, however, whether the expression of the Kv1.1 subunit, constituting Kv1 channels, can be specifically regulated in brain areas important for learning and memory processing. Radioactive in situ hybridization was used to evaluate the content of Kv1.1 α-subunit mRNA in the olfactory bulb, ventral, and dorsal hippocampus at different stages of an odor-discrimination associative task in rats. Naive, conditioned, and pseudoconditioned animals were sacrificed at different times either prior to a two-odor significance learning or after odor discrimination was established. Important decreases of Kv1.1 mRNA levels were transiently observed in the ventral hippocampus before successful learning when compared with the pseudoconditioned group. Moreover, temporal group analysis showed significant labeling alterations in the hippocampus of conditioned and pseudoconditioned groups throughout the training. Finally, Kv1.1 mRNA levels in the hippocampus were positively correlated with odor-reward association learning in rats that were beginning to discriminate between odors. These findings indicate that the Kv1.1 subunit is transiently down-regulated in the early stages of learning and suggest that Kv1 channel expression regulation is critical for the modification of neuronal substrates underlying new information acquisition.  相似文献   
98.
The psychological orientation treats semantics as a matter of idealized computation over symbolic structures, and semantic relations like denotation as relations between linguistic expressions and these structures. I argue that results similar to Gödel’s incompleteness theorems and Tarski’s theorem on truth create foundational difficulties for this view of semantics.  相似文献   
99.
We conducted six experiments to examine how manipulating perception versus action affects perception–action recalibration in real and imagined blindfolded walking tasks. Participants first performed a distance estimation task (pretest) and then walked through an immersive virtual environment on a treadmill for 10 min. Participants then repeated the distance estimation task (posttest), the results of which were compared with their pretest performance. In Experiments 1a, 2a, and 3a, participants walked at a normal speed during recalibration, but the rate of visual motion was either twice as fast or half as fast as the participants' walking speed. In Experiments 1b, 2b, and 3b, the rate of visual motion was kept constant, but participants walked at either a faster or a slower speed. During pre- and posttest, we used either a blindfolded walking distance estimation task or an imagined walking distance estimation task. Additionally, participants performed the pretest and posttest distance estimation tasks in either the real environment or the virtual environment. With blindfolded walking as the distance estimation task for pre- and posttest, we found a recalibration effect when either the rate of visual motion or the walking speed was manipulated during the recalibration phase. With imagined walking as the distance estimation task, we found a recalibration effect when the rate of visual motion was manipulated, but not when the walking speed was manipulated in both the real environment and the virtual environment. Discussion focuses on how spatial-updating processes operate on perception and action and on representation and action.  相似文献   
100.
Online social networking is vastly popular and permits its members to post their thoughts as microblogs, an opportunity that people exploit, on Facebook alone, over 30 million times an hour. Such trivial ephemera, one might think, should vanish quickly from memory; conversely, they may comprise the sort of information that our memories are tuned to recognize, if that which we readily generate, we also readily store. In the first two experiments, participants’ memory for Facebook posts was found to be strikingly stronger than their memory for human faces or sentences from books—a magnitude comparable to the difference in memory strength between amnesics and healthy controls. The second experiment suggested that this difference is not due to Facebook posts spontaneously generating social elaboration, because memory for posts is enhanced as much by adding social elaboration as is memory for book sentences. Our final experiment, using headlines, sentences, and reader comments from articles, suggested that the remarkable memory for microblogs is also not due to their completeness or simply their topic, but may be a more general phenomenon of their being the largely spontaneous and natural emanations of the human mind.  相似文献   
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