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895.
Peter D. Mott 《Theoretical medicine and bioethics》1990,11(2):95-102
The issues involved in decision making about the aggressiveness of future medical care for older persons are explored. They are related to population trends, the heterogeneity of older persons and a variety of factors involved in individual preferences. Case studies are presented to illustrate these points, as well as a review of pertinent literature. The argument is offered that, considering these many factors, a system of flexible, individualized care by informed patient preference, is more rational than the rationing of technological services by age. 相似文献
896.
C. D. L. Wynne 《Behavior research methods》1990,22(1):27-33
A system of interfaces for the Commodore 64 (C-64) microcomputer for use in the operant laboratory is described. This system frees the experimenter from limitations on the number of I/O lines available on the user port of the C-64 and offers the control of operant chambers for a low cost. Subroutines in machine code to control the interfaces, offering millisecond timing of external events, are presented. A sample BASIC program demonstrates how the subroutines are called from BASIC to run a simple discrimination experiment. 相似文献
897.
The orienting response (OR) is a specific behavioral act directed towards extraction of information from the environment. Head and eye movements represent only the tip of the iceberg of internal responses, which includes vascular modifications, EEG changes, and event-related potentials. Two mechanisms of the OR have to be differentiated: voluntary and involuntary. In the event-related potential, such a differentiation is expressed in mismatch negativity (involuntary effect) and processing negativity (voluntary effect). Single unit studies have shown that hippocampal neurones are simulating specific features of the OR as a response to novelty. Repeated presentation of stimuli results in a selective habituation of novelty detectors in hippocampus and of the OR. The trace of a standard stimulus formed at the level of hippocampal neurones matches the features of the standard stimulus and can be called a “neuronal model of the stimulus.” The OR is triggered by mismatch between the test stimulus and the elaborated neuronal model, and is activated by verbal instruction, by reinforcement during the initial stage of conditioned reflex elaboration, and by differentiation of signal and non-signal stimuli. A promising new area of practical application of the OR lies in the evaluation of a corridor of optimal functional state for efficient computer-based learning. Registration of the OR and defensive responses can be used for an objective evaluation of the functional state of the student, or, in a wider sense, of the industrial operator. New avenues of OR research are opened by recent techniques that isolate single-trial event related potentials, and their correlation with autonomic and behavioral manifestations of the OR. The combination of single unit recording with such isolated event related potentials can elucidate the neuronal basis of OR generation. Intracellular recording combined with dye injection can be used for analysis of the synaptic contacts involved in generation of the OR. Integration of macro and micro levels of OR organization can be achieved in a computerized model that can be used for simulation and planning of experiments. A step-by-step improvement of the model will accumulate knowledge about the OR as an important mechanism of information processing. 相似文献
898.
The Word Speaks to the Faustian Man. Som Raj Gupta. Delhi, Motilal Banarsidass. 455+xvi pp., Rs. 500
A History of Indian Buddhism, From Sākyamuni to Early Mahāyāna. Hirakawa Akira, translated and edited by Paul Groner, 1990. Asian Studies at Hawaii, No. 36. Honolulu, HI, University of Hawaii Press. xix +402, £33.25
The Doctrine of the Upanisads and the Early Buddhism. Hermann Oldenberg, translated by Shridhar B. Shrotri, 1991. Delhi, Motilal Banarsidass. Rs. 225
Evil and the Mystics’ God: Towards a Mystical Theodicy. Michael Stoeber. London, Macmillan. x+225 pp., £40 相似文献
899.
Abstract— In our discussion of the articles in this Special Section, we ask how well the various methods employed in these investigations can be made to converge on a common issue. We review how current evidence from positron emission tomography, studies of event-related potentials, cognitive methods, lesion studies, and network models relates to the mental processing of an ambiguous word. While many puzzles remain, we are impressed by the promising possibility of bringing these different methods together to deal with an issue central to cognition. 相似文献
900.
Diana D. Raymond Peter W. Dowrick Chris L. Kleinke 《Counselling psychology quarterly》1993,6(3):193-200
Despite the growing popularity of watching oneself on videotape, little systematic research has been conducted determine viewers' affective responses to video replay. This study addresses the question: what affective responses do women have when they view themselves for the first time on unedited videotape, in comparison to their responses when they view a peer or nature scenes on videotape? Affective responses were measured in three ways: self-report, physiological, and behavioral. Subjects who viewed themselves reported more negative feelings and anxiety, and smiled more frequently than subjects who watched another person or nature scenes on video. Subjects with high private self-consciousness had higher mean arterial blood pressures when viewing themselves than did subjects with low private self-consciousness. Overall, the implications for seeing oneself on video point to potential embarrassment but generally moderate effects. 相似文献