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991.
Complete stops at a high-traffic intersection on the campus of a public university were increased with a prompting and consequence intervention. Data were collected at two opposing stop signs (Stop A and Stop B); however, the intervention was implemented only at Stop A. During the intervention, a volunteer stood next to Stop A holding a poster that read, "Please Stop--I Care," with "Thank You For Stopping" on the reverse side. The poster was held by the volunteer so that drivers approaching Stop A could read the sign. Drivers approaching Stop B could see the volunteer but could not read the sign. When vehicles approaching Stop A made a complete stop, the volunteer flashed the "thank you" side of the poster to the driver. The strategy was evaluated using a multielement design. The intervention increased stops completed at Stop A from a baseline average of 13% to an intervention average of 52%. Stop B also showed improved stopping, from a baseline average of 6% to an intervention average of 28%. Data showed no relation between complete stops made and the drivers' use of turn signals and safety belts.  相似文献   
992.
Object parts are signaled by concave discontinuities in shape contours. In seven experiments, we examined whether 5- and 6 1/2-month-olds are sensitive to concavities as special aspects of contours. Infants of both ages detected discrepant concave elements amid convex distractors but failed to discriminate convex elements among concave distractors. This discrimination asymmetry is analogous to the finding that concave targets among convex distractors pop out for adults, whereas convex targets among concave distractors do not. Thus, during infancy, as during adulthood, concavities appear to be salient regions of shape contours. The current study also found that infants' detection of concavity is impaired if the contours that define concavity and convexity are not part of closed shapes. Thus, for infants, as for adults, concavities and convexities are defined more readily in the contours of closed shapes. Taken together, the results suggest that some basic aspects of part perception from shape contours are available by at least 5 months of age.  相似文献   
993.
Sustaining attention and successfully engaging with others in collaborative play are important accomplishments focused on in preschool classrooms and childcare centers. In addition, music is frequently used in early childhood classrooms, and even recommended as an environmental feature to motivate and regulate children's behavior. Although pretend play provides appealing opportunities for developing these social abilities, no studies to date have explored the use of music as a tool to motivate and sustain constructive and social pretend play. Results from the current study indicate that within 1 preschool classroom, more sustained play (with fewer interruptions) occurred when music played as compared to when no music played in the background. In addition, significantly more dyadic play occurred when slower music played in the background, than when no music played.  相似文献   
994.
The study was done to check replication of changes in sensitivity with a simple simulator as had been obtained in an experiment using the real road situation. Another purpose was to control simulator sickness which could have confounded data from testing with a simulator or in actual driving. Sensitivity of the drivers (72 healthy young adults, M age = 24 yr., SD = 5) while performing the driving task was measured in terms of subjective ratings of simulator sickness and affect, and physiological measures (i.e., galvanic skin responses and skin temperature) at different driving speeds and in driving mode conditions, using a simple vehicle simulator. Analysis showed measures of drivers' state, including simulator sickness, physiological indices, and subjective reports, increased with driving speed (30 --> 90 -->120 km/hr.) and driving mode change from the regular speed to sudden increasing to sudden decreasing speeds. Particularly, the results suggest that the increased autonomic nervous activation induces increase of rated simulator sickness. Based upon the same tendency in change of the simulator sickness and physiological state with driving speed and driving mode conditions, it was concluded that, if the results obtained from the simulator experiment can be generalized to the real situation, the simulator sickness must be considered a confounding factor. The results also suggest that the changes in human sensitivity are dependent upon aspects related to speed of a vehicle and driving mode.  相似文献   
995.
The grip strength of 214 independently ambulatory Chinese older adults (M age = 75.1 +/- 7.0 yr.) was measured, and preliminary mean values presented. Their previous occupations were recorded, and the physical demands of those occupations in terms of oxygen consumption and work done were classified. Grip strength generally decreased across age groups. The physical demand of individuals' previous occupations had significant associations with grip strength, for example, participants who previously worked as construction site workers had a greater grip strength than those who worked previously as office workers.  相似文献   
996.
Potential age-related differences in the memory processes that underlie visual search are examined in the present study. Using a dynamic, gaze-contingent search paradigm developed to assess memory for previously examined distractors, older adults demonstrated no memory deficit. Surprisingly, older adults made fewer refixations compared to their younger counterparts, indicating better memory for previously inspected objects. This improved memory was not the result of a speed-accuracy trade-off or larger Inhibition-of-Return effects for older than for younger adults. Additional analyses suggested that older adults may derive their benefit from finer spatial encoding of search items. These findings suggest that some of the memory processes that support visual search are relatively age invariant.  相似文献   
997.
Research on turnover in academia suggests faculty primarily resign to obtain higher salaries and for personal reasons; however, the samples of most such studies have been from research institutions. Correlates were examined for turnover intentions among 190 faculty members at a university that emphasized teaching. Although current turnover intention was low, seven measures of satisfaction explained 31.5% of the variability in turnover intent, and satisfaction with pay, work itself, and teaching/service load together explained 26% of the variance. Findings support the hypothesis that salary is an important element in explaining turnover consideration at teaching institutions. Although satisfaction with collegial relations was related significantly to turnover intent, it was not as important as some of the other characteristics.  相似文献   
998.
There is great interest in the relationships between memory span tasks and cognitive abilities. However, the causes underlying their correlation remain unknown. In the present article, five key data sets were reanalyzed according to two criteria: They must consider complex span tasks (so-called working memory [WM] tasks) and simple span tasks (so-called short-term memory [STM] tasks), and they must comprise cognitive ability measures. The obtained results offer several points of interest. First, memory span tasks should be conceived from a hierarchical perspective: They comprise both general and specific components. Second, the general component explains about four times the variance explained by the specific components. Third, STM and WM measures are closely related. Fourth, STM and WM measures share the same common variance with cognitive abilities. Finally, the strong relationship usually found between memory span tasks and cognitive abilities could be tentatively interpreted by the component shared by STM and WM--namely, the capacity for temporarily preserving a reliable memory representation of any given information.  相似文献   
999.
It is difficult to perform two tasks at the same time. Such performance limitations are exemplified by the psychological refractory period (PRP): when participants make distinct motor responses to two stimuli presented in rapid succession, the response to the second stimulus is increasingly slowed as the time interval between the two stimuli is decreased. This impairment is thought to reflect a central limitation in selecting the appropriate response to each stimulus, but not in perceptually encoding the stimuli. In the present study, it was sought to determine which brain regions are specifically involved in response selection under dual-task conditions by contrasting fMRI brain activity measured from a response selection manipulation that increased dual-task costs, with brain activity measured from an equally demanding manipulation that affected perceptual visibility. While a number of parieto-frontal areas involved in response selection were activated by both dual-task manipulations, the dorsal pre-motor cortex, and to a lesser extent the inferior frontal cortex, were specifically engaged by the response selection manipulation. These results suggest that the pre-motor cortex is an important neural locus of response selection limitation under dual-task situations.  相似文献   
1000.
P. G. Roma, A. Silberberg, A. M. Ruggiero, and S. J. Suomi (2006) noted that the results S. F. Brosnan and F. B. M. de Waal (2003) attributed to inequity aversion could also be explained as a frustration effect. Roma et al. redressed this confound by designing a procedure that could have supported either of these interpretations. Nevertheless, they found that only a frustration effect accounted for both their data and those of Brosnan and de Waal (2003). The criticisms Brosnan and de Waal (2006) offered of Roma et al. ignored the fact that Brosnan and de Waal's (2003) research design was not capable of offering an unequivocal demonstration of inequity aversion. This conclusion holds no matter what the claimed inadequacies of Roma et al.'s procedures might have been. Caution is urged in inferring the existence of inequity aversion in nonhuman primates.  相似文献   
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