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261.
Prehension movements of the right hand were recorded in a right-handed man (AC), with an injury to the left posterior parietal cortex (PPC) and with a section of the left half of the splenium. The kinematic analysis of AC's grasping movements in direct and perturbed conditions was compared to that of five control subjects. A novel effect in prehension was revealed--a hemispace effect--in healthy controls only. Movements to the left hemispace were faster, longer, and with a smaller grasp aperture; perturbation of both object position and distance resulted in the attenuation of the direction effect on movement time and the time to velocity peak, with a reverse pattern in the time to maximum grip aperture. Nevertheless, the correlation between transport velocity amplitude and grasp aperture remained stable in both perturbed and non-perturbed movements, reflecting the coordination between reaching and grasping in control subjects. In contrast, transport and grasp, as well as their coordination in both direct and perturbed conditions, were negatively affected by the PPC and splenium lesion in AC, suggesting that transport and grasp rely on two functionally identifiable subsystems.  相似文献   
262.
The Schön misconduct case has been widely publicized in the media and has sparked intense discussions within and outside the scientific community about general issues of science ethics. This paper analyses the Report of the official Committee charged with the investigation in order to show that what at first seems to be a quite uncontroversial case, turns out to be an accumulation of many interesting and non-trivial questions (of both ethical and philosophical interest). In particular, the paper intends to show that daily scientific practices are structurally permeated by chronic problems; this has serious consequences for how practicing scientists assess their work in general, and scientific misconduct in particular. A philosophical approach is proposed that sees scientific method and scientific ethics as inextricably interwoven. Furthermore, the paper intends to show that the definition of co-authorship that the members of the Committee use, although perhaps clear in theory, proves highly problematic in practice and raises more questions that it answers. A final plea is made for a more self-reflecting attitude of scientists as far as the moral and methodological profile of science is concerned as a key element for improving not only their scientific achievements, but also their assessment of problematic cases.  相似文献   
263.
Over the last 25 years, a small but growing body of research on research behavior has slowly provided a more complete and critical understanding of research practices, particularly in the biomedical and behavioral sciences. The results of this research suggest that some earlier assumptions about irresponsible conduct are not reliable, leading to the conclusion that there is a need to change the way we think about and regulate research behavior. This paper begins with suggestions for more precise definitions of the terms "responsible conduct of research," "research ethics," and "research integrity." It then summarizes the findings presented in some of the more important studies of research behavior, looking first at levels of occurrence and then impact. Based on this summary, the paper concludes with general observations about priorities and recommendations for steps to improve the effectiveness of efforts to respond to misconduct and foster higher standards for integrity in research.  相似文献   
264.
The neural bases of timing mechanisms in the second-to-minute range are currently investigated using multidisciplinary approaches. This paper documents the involvement of the supplementary motor area (SMA) in the encoding of target durations by reporting convergent fMRI data from motor and perceptual timing tasks. Event-related fMRI was used in two temporal procedures, involving (1) the production of an accurate interval as compared to an accurate force, and (2) a dual-task of time and colour discrimination with parametric manipulation of the level of attention attributed to each parameter. The first study revealed greater activation of the SMA proper in skilful control of time compared to force. The second showed that increasing attentional allocation to time increased activity in a cortico-striatal network including the pre-SMA (in contrast with the occipital cortex for increasing attention to colour). Further, the SMA proper was sensitive to the attentional modulation cued prior to the time processing period. Taken together, these data and related literature suggest that the SMA plays a key role in time processing as part of the striato-cortical pathway previously identified by animal studies, human neuropsychology and neuroimaging.  相似文献   
265.
This article provides a critical assessment of evidence for the claim of experienced clinicians that proper body alignment will ameliorate the feeding problems of patients with cerebral palsy and related neuromotor disorders and reduce the risk of aspiration. While there is evidence that alignment reduces extensor tone and improves feeding, further research is needed to determine whether this population's high risk for aspiration can be reduced by alignment.  相似文献   
266.
This study investigated gender differences on memory processing using event-related potentials (ERPs). Behavioral data and ERPs were recorded in 16 males and 10 females during a recognition memory task for faces. The behavioral data results showed that females performed better than males. Gender differences on ERPs were evidenced over anterior locations and involve the modulation of two spatially and temporally distinct components. These results are in general accordance with the view that males and females differ in the cognitive strategies they use to process information. Specifically, they could differ in their abilities to maintain information over interference and in the processing of the intrinsic contextual attributes of items, respectively, associated with the modulation of two anterior components. These interpretations lend support to the view that processing in females entails more detailed elaboration of information content than in males. Processing in males is more likely driven by schemas or overall information theme.  相似文献   
267.
The present study examines controlled and automatic uses of memory in clinically depressed patients by applying the Process Dissociation Procedure developed by Jacoby (1991) to a stem completion memory task with short and long retention intervals. The results show that the contribution of controlled processes is lower in depressed patients than in controls, especially for the longest retention interval, whereas the contribution of automatic processes is equivalent in both groups and unaffected by the length of the retention interval. These findings are discussed in a cognitive control framework.  相似文献   
268.
269.
Because of very real practical constraints, conditions in animal shelters are often reminiscent of those in early primate deprivation studies. Dogs are frequently surrendered to shelters because of behavior problems, and aspects of the shelter environment may induce anomalous behavior, increasing the chances that adopted dogs will be returned to the shelters. Comparative psychologists, psychobiologists, and other behavioral scientists possess the knowledge and techniques to help shelters intervene in this cycle. Experience suggests human interaction and the application of basic conditioning procedures can reduce the impact of the shelter environment, and ease the transition into the adoptive home. A program developed to meet these goals is described. Shelters can provide opportunities both for the training of students in animal-related exercises and for limited applied research. Behavioral scientists stand in a unique position to help transform conditions in animal shelters to the benefit of all involved.  相似文献   
270.
In this paper I use the concept of forbidden knowledge to explore questions about putting limits on science. Science has generally been understood to seek and produce objective truth, and this understanding of science has grounded its claim to freedom of inquiry. What happens to decision making about science when this claim to objective, disinterested truth is rejected? There are two changes that must be made to update the idea of forbidden knowledge for modern science. The first is to shift from presuming that decisions to constrain or even forbid knowledge can be made from a position of omniscience (perfect knowledge) to recognizing that such decisions made by human beings are made from a position of limited or partial knowledge. The second is to reject the idea that knowledge is objective and disinterested and accept that knowledge (even scientific knowledge) is interested. In particular, choices about what knowledge gets created are normative, value choices. When these two changes are made to the idea of forbidden knowledge, questions about limiting or forbidding lines of inquiry are shown to distract attention from the more important matters of who makes and how decisions are made about what knowledge is produced. Much more attention should be focused on choosing directions in science, and as this is done, the matter of whether constraints should be placed on science will fall into place.  相似文献   
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