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251.
252.
A number of investigators have suggested that affective states influence the focus of attention. One recent proposal is that negative moods increase self-focus. This review considers the evidence that bears on this hypothesis. Conceptual issues pertaining to the construct of self-focus are discussed first. Next, the various parameters that influence attentional focus are presented in order to provide a way of organizing the mood/selffocus literature. Studies that have used state measures of mood and self-focus are considered in this context. Methodological limitations of existing studies are discussed and directions for future work provided. 相似文献
253.
I P Pavlov 《Integrative Physiological and Behavioral Science》1992,27(3):270-8; discussion 267-70
On 25 September, 1923, two days before his 74th birthday, Ivan Petrovich Pavlov stood before a class of medical students assembled in the auditorium of his Alma Mater, the Military Medical Academy in Leningrad. Pavlov, the recipient of the Nobel prize in medicine in 1904 for his work in physiology, was about to address his first class of the new academic year, and, as was his custom, he had prepared his first lecture on a general theme. This was an especially significant address, however, for in it Pavlov reviewed the impressions he had gathered during his travels in Western Europe and the United States in the summer of 1923, and he criticised the prevailing ideology of Soviet communism by attacking the ideas of Nikolai Ivanovich Bukharin, then the leading expositor of Bolshevik Marxism. An English translation of the lecture is printed below. 相似文献
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256.
James A. Bashford Keri R. Riener Richard M. Warren 《Attention, perception & psychophysics》1992,51(3):211-217
Outside of the laboratory, listening conditions are often less than ideal, and when attending to sounds from a particular source, portions are often obliterated by extraneous noises. However, listeners possess rather elegant reconstructive mechanisms. Restoration can be complete, so that missing segments are indistinguishable from those actually present and the listener is unaware that the signal is fragmented. This phenomenon, called temporal induction (TI), has been studied extensively with nonverbal signals and to a lesser extent with speech. Earlier studies have demonstrated that TI can produce illusory continuity spanning gaps of a few hundred milliseconds when portions of a signal are replaced by a louder sound capable of masking the signal were it actually present. The present study employed various types of speech signals with periodic gaps and measured the effects upon intelligibility produced by filling these gaps with noises. Enhancement of intelligibility through multiple phonemic restoration occurred when the acoustic requirements for TI were met and when sufficient contextual information was available in the remaining speech fragments. It appears that phonemic restoration is a specialized form of TI that uses linguistic skills for the reconstruction of obliterated speech. 相似文献
257.
A new method for determining the minimum number of observations per subject needed to achieve a specific generalizability coefficient is presented. This method, which consists of a branch-and-bound algorithm, allows for the employment of constraints specified by the investigator. 相似文献
258.
This paper studies a class of infinite-valued predicate logics. A sufficient condition for axiomatizability of logics from that class is given.To the memory of Jerzy Supecki 相似文献
259.
ACTH 4-9 analog can retard spatial alternation learning in brain damaged and normal rats 总被引:1,自引:0,他引:1
Thirty adult male hooded rats (Long-Evans strain) were assigned randomly to one of three lesion groups (n = 10) and prepared with medial frontal, posterior parietal, or sham neocortical injuries. Following a recovery interval of 10-12 days, access to water was limited to 30 min per day and the rats were shaped to traverse a T-maze for a reward of sweetened water. After a pretraining criterion was attained, osmotic minipumps (Alzet 2002) were installed subcutaneously. The minipumps delivered chronically for the next 14 to 15 days either 0 or 1.2 micrograms of ACTH 4-9 dissolved in bacteriostatic saline per day while the rats were trained on a reinforced spatial alternation task. Analysis of the number of errors made to a criterion of at least 80% correct alternations in two consecutive training sessions, or a ceiling of 62 errors (attained by two rats with parietal lesions), revealed that learning was impaired in the rats with parietal injuries. Contrary to our hypothesis, animals receiving ACTH 4-9 committed more errors than their counterparts receiving only saline. 相似文献
260.
Age-dependent facilitation of taste-footshock conditioning by prior exposure to the training context
Among adult rats, gustatory stimuli are easily associated with illness, but not with external unconditioned stimuli such as footshock. Recent evidence indicates, however, that this cue-to-consequence specificity may vary ontongenetically. The present studies examined the acquisition of an aversion to a taste paired with footshock in 5- and 15-day-old rats. Consistent with previous reports, 5-day-old rats avoided the taste that preceded footshock, while 15-day-old subjects did not express an aversion to the taste paired with footshock. Exposure to the training context for either 1 or 5 h prior to conditioning disrupted taste-footshock conditioning in the 5-day-old subjects. For the 15-day-old subjects, 1 h of pre-conditioning exposure to the training context had no effect on conditioning, whereas a longer duration of preexposure promoted conditioning to the taste cue. The results suggest ontogenetic differences in stimulus selection. 相似文献