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31.
Previously reported experiments demonstrated changes in the relation of visual direction to retinal locus for stimulation during voluntary saccades as compared to this relation before saccade initiation. The quantitative features of these results led to the prediction, confirmed in the present experiments, that there are shifts in visual direction for stimulation presented before the saccade itself. In the present report, monotonically increasing shifts were mapped with stimuli presented as early as 240 msec before the saccade up to the saccade itself. Such shifts cannot be accounted for readily by “inflowing” processes, and while “outflowing” processes seem to be implicated, their quantitative characteristics would need to be considerably different from those required by classical outflow theories. 相似文献
32.
Summary The effect of mental arithmetic (standard multiplication, with eyes closed) and eye-opening on the power spectral density of the EEG (recorded bipolarly from occipital and parietal regions) have been compared. The EEG was recorded on magnetic tape from normal subjects, (medical students) in a constant environment and subsequently analysed by an analogue computer (Noratom Instrument for Statistical Analysis and Computation, ISAC).Absolute measurements made from 15 subjects with eyes closed have shown that peaks of power at 10 Hz vary from 9 to 46 V2 per Hz. Qualitatively, suppression of power at 10 Hz is greater due to eye-opening than mental arithmetic.Analysis of pooled power spectral density functions from 11 subjects showed that the effect of eye-opening differed significantly from the effect of mental arithmetic at 2.5 and 12.5 Hz. Suppression of lower frequency alpha activity was more pronounced during calculation than during eye-opening. Compared with the eyes closed condition, eye-opening showed a highly significant suppression at 10 and 12.5 Hz (alpha activity) and from 15 to 25 Hz (beta activity). Mental arithmetic induced significant suppression at 7.5 and 10 Hz and from 15 to 30 Hz. Eye-opening enhanced lower frequency activity which calculation suppressed.Variation was greater between first, second and third calculations in pooled power spectral densities than between corresponding eye-opening epochs. It is suggested that these differences in effects of eye-opening and mental arithmetic reflect differences in underlying cerebral activity, rather than that an underlying factor common to both effects may be orbital in origin. 相似文献
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34.
There is evidence that adaptation to chronic illness may be affected by psychological factors, especially how patients appraise and cope with the stress of their illness. The purpose of the present study was to examine the relationship of stress appraisal and coping responses to multiple behavioral indices of illness adjustment among patients with diverse chronic medical conditions. One hundred and one patients admitted to a multidisciplinary medicine/psychiatry unit completed measures of functional impairment, depression, symptom severity, and the Ways of Coping Checklist--Revised. Hierarchical regression analyses indicated that emotion-focused coping was positively related to poor psychosocial adjustment and depression after controlling for physician rated disease severity. Appraising chronic illness as holding one back predicted greater emotion-focused coping responses and poorer adjustment to illness. The use of problem-focused coping strategies was generally unrelated to illness adjustment. These findings suggest the presence of an emotion-focused coping triad consisting of wishful thinking, self blame, and avoidance, all of which appear to be maladaptive strategies when coping with chronic medical conditions. Implications for coping skills training and the need for longitudinal research is discussed. 相似文献
35.
Rodger Beehler 《Studies in Philosophy and Education》1990,10(4):315-335
The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise. 相似文献
36.
Jordan Howard Sobel 《The Philosophical quarterly》1997,47(186):55-72
A theory of right action is implicit in Hume's delineation of the virtues. It gives qualified priority to 'rules of justice' as Hume's remarks on 'that species of utility which attends this virtue' require. It is a useful actual-rule, not an ideal possible-rule, purely utilitarian theory that discounts rules of justice in 'extraordinary cases', has a problem when rules conflict, and invites the question 'Why not hark directly to the supreme law of utility in every case?'. It does not reflect contractarian considerations of mutuality of interests evident in Hume's texts, which while sometimes relevant to what is reasonable, are in his view never also relevant to what is moral. 相似文献
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38.
Jörg R. J. Schirra 《Kognitionswissenschaft》1997,6(4):177-195
How can we explain that an assertion on something perceived can be understood in the same manner by somebody who cannot perceive that scene? This problem bases the interest in computational linguistics in how listener modeling could possibly be harmonized with reference semantics. Mental images substituting real perception appear as a way out. The architecture of the listener model has to be adapted to the creation and use of such pictorial data structures. Furthermore, the relation between the latter and a verbal (i. e., propositional) representation must be understood. The resulting architecture of a listener model with reference semantics can be employed to solve communicational problems from three general classes in a better way, as is demonstrated by an example implementation. 相似文献
39.
Jordan Howard Sobel 《Synthese》1996,108(1):11-61
A person who does not have good intellectual reasons for believing in God can, depending on his probabilities and values for consequences of believing, have good practical reasons. Pascalian wagers founded on a variety of possible probability/value profiles are examined from a Bayesian perspective central to which is the idea that states and options are pragmatically reasonable only if they maximize subjective expected value. Attention is paid to problems posed by representations of values by Cantorian infinities. An appendix attends to Robinsonian hyperreals. Another appendix presents for comparison Newcomb's Problem and a problem in some ways like it suggested, I think, by ideas of John Calvin. 相似文献
40.
T Jordan 《Perceptual and motor skills》1978,46(2):667-674
30 elderly subjects were matched with 30 young subjects and tested on a kinesthetic short-term memory task which required the replication of criterion moves after a variable retention interval under conditions of either rest, differing interpolated movement tasks, or mental activity. A visual control condition was used. Differing interference and temporal decrements were observed. Both old and young subjects differed significantly between sighted and blindfold conditions; however, there was no difference between the performance of the old and the young in the blindfold (kinesthetic) condition. These findings were discussed with respect to practical implications for the retraining of old subjects on certain motor tasks. 相似文献