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211.
212.
To investigate the nature of the frames of reference used to control an arm movement aimed at a visual target, we studied the accuracy of movements differing by the initial arm and eye positions. The results support the assumption that in darkness target location is internally represented in an egocentric frame of reference. Furthermore, when movements carried out with and without eye saccade are compared, it appears that foveating the target changes the reference used to generate the reaching arm movements, that is, the oculocentric reference is replaced by a head-trunk reference. An explanation for this phenomenon could be that a steady body-related landmark is needed to insure stable registering of the target location in the surrounding space, despite displacement of the body segments with respect to one another. 相似文献
213.
214.
Hanser examines Derek Parfit's contention in his treatise on rationalism, Reasons and Persons (Oxford University Press; 1984) that acts that are not reproductive in nature can nonetheless predictably affect the identities of future people, and that this fact has unexpected and important consequences for ethical theory. Hanser argues tht this fact is not as significant as Parfit believes it to be. The arguments of both scholars concern the morality of choices that, while causing future persons to be badly off, do not make them worse off than they would have been if the choices had not been made. Hanser concludes his essay with a discussion of responsibility for acts that will affect the health of future offspring. 相似文献
215.
Levitt M 《Science and engineering ethics》1997,3(3):305-315
Empirical research with young people in Finland, Germany, Spain and Britain was carried out as part of the BIOCULT project
funded by the European Union. The project focused on their attitudes to biotechnology and, in particular, the formation of
arguments about risk and safety. This paper looks at the responses of 14–18 year olds to a story about the so called anti-obesity
gene, in the form of advice to a friend who is taking it. The majority advised against taking it with some differences by
gender and country. Most reservations were on grounds of safety and the feeling that ‘natural’ ways to lose weight are better:
A minority questioned the idea of striving for a ‘perfect’ body. The types of arguments used by the young people reveal underlying
perspectives on the place of human beings in the world and whether they have a right to manipulate nature and their own bodies.
Marie Levitt is a sociologist with research interests in attitudes and values in relation to biotechnology, health and religion. 相似文献
216.
Peters M 《Journal of motor behavior》1997,29(4):290-296
Humans are a throwing species just as much as a talking species (Calvin, 1982), but preadaptations for throwing remain largely unexplored. The ability of undergraduate students (N = 165) to intercept a stimulus with a thrown object was determined for 10 stimulus speeds, ranging from 2 to 5 m/s. The inclusion of a condition in which the moving stimulus was intercepted. via button press allowed the role of the perceptual aspect of velocity estimation to be evaluated separately from the act of throwing. Gender differences were observed in both the button and the throwing intercept tasks: The men had smaller timing errors and higher accuracy than the women. Contrary to expectations, the male and female patterns of intercept errors as a function of stimulus speed were more similar in the throwing task than in the button intercept task 相似文献
217.
Crosbie J Williams A Lattal K Anderson M 《Journal of the experimental analysis of behavior》1997,68(2):161-175
The principal aim of the present experiments was to assess whether punishment increased or decreased the rate of unpunished behavior (contrast and induction, respectively) for which reinforcement rate was held constant, with physical and nonphysical punishers (electric shock and response cost), pigeon and human subjects, signaled and unsignaled components (multiple and mixed schedules), and the presence or absence of a blackout period between components. Across the three experiments there were 20 punishment conditions. Induction was found in nine of those, less consistent response-rate reduction was found in three, contrast was found in four, and in four there was no change in responding from conditions without punishment. Contrast occurred consistently only with multiple schedules during the first exposure to electric-shock punishment. Induction and no change, however, were found with every combination of the independent variables studied. Four conclusions regarding the interactions between punished and unpunished responding emerged from the present results: (a) Both contrast and induction occurred with the reinforcement rate held constant and a blackout between components, (b) induction was more common than contrast, (c) contrast occurred only in the presence of a stimulus different from that correlated with the punisher, and (d) contrast diminished with prolonged exposure to punishment. None of the current theoretical accounts of punishment contrast can explain the present results. 相似文献
218.
Engel JD Kane G Jones DL Lynn-McHale D Swartz M Durbin P Klingen D 《The Journal of medical humanities》1997,18(3):193-208
This study describes the results of a retrospective review of patients' charts who had an advanced directive (AD) and who were hospitalized in a tertiary, acute care teaching hospital. The purpose of the review was to understand from clinical, sociological, ethical and legal perspectives the nature and utility of ADs. Findings and implications of the review are discussed in terms of: patient demographics; diagnoses; quality of ADs; influence of ADs on clinical decisions; and legal aspects of ADs. 相似文献
219.
This paper examines ethical issues related to medical practices with children and adults who are members of a linguistic and cultural minority known as the DEAF-WORLD. Members of that culture characteristically have hearing parents and are treated by hearing professionals whose values, particularly concerning language, speech, and hearing, are typically quite different from their own. That disparity has long fueled a debate on several ethical issues, most recently the merits of cochlear implant surgery for DEAF children. We explore whether that surgery would be ethical if implants could deliver close to normal hearing for most implanted children, thereby diminishing the ranks of the DEAF-WORLD. The ethical implications of eugenic practices with the DEAF are explored, as are ethical quandaries in parental surrogacy for DEAF children, and their parallels in transracial adoption. 相似文献
220.
Mosier KL Skitka LJ Heers S Burdick M 《The International journal of aviation psychology》1997,8(1):47-63
Automated aids and decision support tools are rapidly becoming indispensable tools in high-technology cockpits and are assuming increasing control of"cognitive" flight tasks, such as calculating fuel-efficient routes, navigating, or detecting and diagnosing system malfunctions and abnormalities. This study was designed to investigate automation bias, a recently documented factor in the use of automated aids and decision support systems. The term refers to omission and commission errors resulting from the use of automated cues as a heuristic replacement for vigilant information seeking and processing. Glass-cockpit pilots flew flight scenarios involving automation events or opportunities for automation-related omission and commission errors. Although experimentally manipulated accountability demands did not significantly impact performance, post hoc analyses revealed that those pilots who reported an internalized perception of "accountability" for their performance and strategies of interaction with the automation were significantly more likely to double-check automated functioning against other cues and less likely to commit errors than those who did not share this perception. Pilots were also lilkely to erroneously "remember" the presence of expected cues when describing their decision-making processes. 相似文献