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Experiments were designed to examine the influence of criterion and feedback information in the learning of a two-dimensional drawing task. Experiment 1 showed that when the task criterion is well known to the subject, the combined presentation of criterion information and information feedback facilitates the rate of acquisition of the skill but not its overall performance level of achievement. Experiment 2 showed that when the task criterion information is not well known to the subject, presentation of criterion information facilitates both the rate of acquisition and the overall performance level and, furthermore, is essential if configuration information feedback is to be utilized effectively. Experiment 3 showed that it is the combined presentation of criterion and configuration information feedback rather than the isolate presentation of either type of information alone, that facilitates learning and performance. Collectively, the findings from the three experiments suggest an interactive effect of prior knowledge by the learner and type of augmented information in facilitating the acquisition of skill, according to the constraints imposed in the task. The data are consistent with the proposal that the degrees of freedom in the information available to support motor skill learning must match the degrees of freedom to be constraint in the perceptual-motor workspace. 相似文献
104.
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
105.
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
106.
Languages differ in their phonological structure and physcholinguists have begun to explore the conseqence, of this fact for speech perception. We review research documenting that listeners attune their perceptual processes finaly to exploit the phonological regularities of their nativ language. As a consequence, these perceptual process are fill-adapted to listening to languages that do not display such, regularities. Thus, not only do late language-learners have trouble speaking a second language, also they do not hear it as native speakers do; worse, they apply their native language listening prosedures which may actually interfere with successful processing of the non-native input. We also present data from studies on infants showing that the initial attuning occurs early in life; very yong infants are sensitive to the relevant phonological regularities which distinguish different languages, and quickly distinguish the native language of their environment from languages with different regularities. 相似文献
107.
Changes in interlimb coupling, and their role in the development of bimanual coordination, were studied longitudinally in 6- to 12-month-old infants (N = 6). Infants were observed while they were reaching for simple objects of 2 different sizes. Their use of a uni-versus bimanual strategy for reaching as well as the coupling of their bimanual movements were compared; progress in bimanual coordination of complementary movements was evaluated on 8 different bimanual tasks. The bimanual tasks involved an asymmetrical cooperation between the 2 hands. Although spatiotemporal coupling of bimanual reaching movements did not decrease during the age period studied, infants around 7 months of age used their 2 hands infrequently for reaching. Occurrences of bimanual reaching were particularly low at the session preceding the first bimanual success at a bimanual task. This suggests that the temporal coincidence between greater independence of the 2 hands and progress in bimanual coordination of complementary movements acts in 2 directions: Infants may be more at ease when using their 2 hands in differentiated patterns as the hands move less in synchrony, but, in turn, they may be less likely to move their hands in synchrony as the anticipate mirror manipulations of the object less. The frequency of bimanual reaches increased toward the end of the 1st year. This might have been caused by an increase in the repertoire of bimanual asymmetrical object manipulations and by the fact that the development of bimanual coordination allows infants to manipulate objects with complementary movements even after a bimanual approach toward the object. 相似文献
108.
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
109.
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
110.