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891.
The role of memory in the Tower of London task 总被引:5,自引:0,他引:5
The Tower of London (TOL) task is widely used as a neuropsychological test of planning. Relatively little is known of the cognitive components of the task, and in particular the role of memory in performance. The current studies on normal adults looked at the role of verbal and spatial working memory in the TOL. The effects of verbal and visuospatial dual-task manipulations on TOL performance were examined in an experiment with 36 participants. Both verbal and visuospatial executive secondary tasks caused poorer performance on the TOL; however, concurrent articulatory suppression enhanced performance. The results suggest that executive and spatial components are important in the task, and raise questions about the role of preplanning in the TOL. 相似文献
892.
K V Sudakov Y V Uryvaev G A Petrov 《Integrative Physiological and Behavioral Science》1999,34(3):150-154
The blood coagulation time as an integral sign of human homeostasis is revealed to be influenced by conscious or unconscious olfactory stimuli through autonomic mechanisms. The hemostasis of subjects with predominance of sympathetic activity is more sensitive to the olfactory stimuli than that of subjects with vagal prevalence. The effects of the olfactory stimuli upon hemostasis in humans support the viewpoint that simultaneous information and physico-chemical processes act together in parallel to play and important role in life activities of human organism (Simonov, 1981; Sudakov, 1995). Emotions, therefore, are essential in the transfer of information from the environment (Anokhin, 1966; Miltner et al., 1994). It is not excluded that even very weak stimuli which are subthreshold for conscious perception might be informational for the organism as those engaging emotional response. 相似文献
893.
Intravenous injection of histamine to rabbits was used as a prototype in an investigation of the mechanism of sudden death due to anaphylaxis and other causes. The "dive" reflex, bradycardia due to activation of the ophthalmic branch of the fifth cranial nerve, was induced in thirty-seven of the animals while they inhaled a very small amount of cigarette smoke. Associated with the resulting bradycardia were lowered blood pH and increased serum content of lactic acid and potassium and increased peripheral arterial constriction with elevation of diastolic blood pressure. Intravenous injection of 1 ml of histamine in the presence of the dive reflex induced potentially fatal ventricular arrhythmia, but no cardiac disturbance when administered while the dive reflex was inactive, thereby strongly suggesting that sudden death in anaphylaxis may involve an overzealous response to a normally protective neural reflex. 相似文献
894.
Sidarta Ribeiro Vikas Goyal Claudio V. Mello Constantine Pavlides 《Learning & memory (Cold Spring Harbor, N.Y.)》1999,6(5):500-508
In most mammalian species studied, two distinct and successive phases of sleep, slow wave (SW), and rapid eye movement (REM), can be recognized on the basis of their EEG profiles and associated behaviors. Both phases have been implicated in the offline sensorimotor processing of daytime events, but the molecular mechanisms remain elusive. We studied brain expression of the plasticity-associated immediate-early gene (IEG) zif-268 during SW and REM sleep in rats exposed to rich sensorimotor experience in the preceding waking period. Whereas nonexposed controls show generalized zif-268 down-regulation during SW and REM sleep, zif-268 is upregulated during REM sleep in the cerebral cortex and the hippocampus of exposed animals. We suggest that this phenomenon represents a window of increased neuronal plasticity during REM sleep that follows enriched waking experience. 相似文献
895.
The research reported in this paper follows the perspective that decision making is a meaningful act that conveys information. Furthermore, the potential meanings associated with decision options may affect the decisions themselves. This idea is examined in the contexts of compensation, donation, and exchange. In general, judgments were relation dependent and meaning dependent. Furthermore, the results show nonmonotonicities and limited substitutability in a pattern that challenges straightforward ways of mapping decisions onto a common currency of utility. 相似文献
896.
Further evidence for feature correlations in semantic memory. 总被引:4,自引:0,他引:4
K McRae G S Cree R Westmacott V R de Sa 《Revue canadienne de psychologie expérimentale》1999,53(4):360-373
The role of feature correlations in semantic memory is a central issue in conceptual representation. In two versions of the feature verification task, participants were faster to verify that a feature (< is juicy >) is part of a concept (grapefruit) if it is strongly rather than weakly intercorrelated with the other features of that concept. Contrasting interactions between feature correlations and SOA were found when the concept versus the feature was presented first. An attractor network model of word meaning that naturally learns and uses feature correlations predicted those interactions. This research provides further evidence that semantic memory includes implicitly learned statistical knowledge of feature relationships, in contrast to theories such as spreading activation networks, in which feature correlations play no role. 相似文献
897.
Research misconduct—Have we reached the turning point at last? 总被引:1,自引:0,他引:1
Jay P 《Science and engineering ethics》1999,5(1):119-122
The laissez-faire attitude towards dishonesty in research has simply created an environment for widespread escalation of the problem. Can we now believe anything we read? Why should we have confidence in an author because of his eminence? Should we automatically accept that clinical trials are always conducted with total integrity? Why have we been afraid to tackle this crisis head-on? 相似文献
898.
Peter B. Clarke 《Journal of Contemporary Religion》1999,14(2):203-216
Brazil's ‘new’ style of Catholicism, essentially the creation of a group of young, charismatic clergy—'pop‐star priests’ or ‘stars of the altar’, as they have become known—appears to have set in train a reversal, in that Latin American country at least, of the ‘walkout’ to evangelical Protestantism that David Martin analysed in Tongues of Fire: The Explosion of Pentecostalism in Latin America (1990). In that volume Martin described the rapid development of Protestantism in Latin America in the twentieth century and particularly from the 1960s as “... an explosion of conservative evangelical religion, a shift toward Pentecostalism, a rejection of ecumenism, and the manifestation among many of those involved of the evangelical capacity to unite modern technology with political conservatism”; (Martin, 1990: 54). During the past year millions of lapsed Catholics, and former Catholics some of whom were part of that ‘explosion’, have become involved in the ‘new’ Catholicism whose emergence illustrates the indispensable role of the media in religious reform and conversion in contemporary society. The article examines the superstructural elements of the ‘new’ Catholicism and compares its positive ‘cosmology’ and worldview with the emphasis on demonization in the teaching and ritual of the controversial, but highly successful evangelical Protestant Church, the Igreja Universal do Reino de Dens (the Universal Church of the Reign of God). This presentation also considers the various responses to the ‘new’ Catholicism which, although responsible for the return to worship of millions of Catholics, has been strongly criticised by both Liberation Theology and the more theologically and liturgically conservative wing within the Roman Catholic Church in Brazil. 相似文献
899.
Peter van Inwagen 《The Journal of Ethics》1999,3(4):343-351
In his classic paper, The Principle of Alternate Possibilities, Harry Frankfurt presented counterexamples to the principle named in his title: A person is morally responsible for what he has done only if he could have done otherwise. He went on to argue that the falsity of the Principle of Alternate Possibilities (PAP) implied that the debate between the compatibilists and the incompatibilists (as regards determinism and the ability to do otherwise) did not have the significance that both parties had attributed to it -- since moral responsibility could exist even if no one was able to do otherwise. I have argued that even if PAP is false, there are other principles that imply that moral responsibility entails the ability to do otherwise, and that these principles are immune to Frankfurt-style counterexamples. Frankfurt has attempted to show that my arguments for this conclusion fail. This paper is a rejoinder to that reply; I argue that he has failed to show this. 相似文献
900.
Tyler S. Lorig David G. elmes David H. Zald Jose V. Pardo 《Behavior research methods》1999,31(2):370-375
A design for an inexpensive and reliable olfactometer is presented. The design has several advantages for fMRI and electrophysiology investigators. These advantages include relatively rapid odorant rise times, computer control, multiple odor administration, and no ferrous materials near the subjects. In addition, the device is contamination resistant, and, because the air is neither warmed nor humidified, it is unlikely to become an incubator for bacteria. The olfactometer is constructed of off-the-shelf chromatography parts that require little modification. 相似文献