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281.
Presented are specific parameters of visual information intake in pilots on the job. The role of eye movements in the process of visual stimulus reception is discussed. Our own study on a MIG-23 flight simulator is presented. The method of oculographic testing of pilots performing professional assignments differing in workload is presented, and the practical implications of oculographic research are discussed.  相似文献   
282.
Three conceptions of general education developed under the titles ‘general,’‘generalist,’ and ‘generalizing’ are matched with appropriate strategies for teaching the Bible. These provide the basis for two points relevant to teaching the Bible in colleges and universities: first, that the prime object of attention is not the Bible, but rather a corporate agreement regarding an educational project; and second, that the ways in which the Bible might be taught will vary, appropriately, according to the ways in which that educational enterprise is understood. A corollary is stated: teachers of the Bible need to be as informed about research in teaching as they are in biblical research.  相似文献   
283.
Bizarre visual symptoms and absurd verbal responses to questions, in a 32-year-old man recovering from a severe asthma episode, suggested a possible conversion disorder with Ganser-like symptoms. Positron Emission Tomography (PET)revealed bilateral lesions involving occipital association cortex and posterior temporal and parietal lobes, most likely infarcts from hypoxia. PET permitted correlation of the patient's specific cortical lesions with his unusual perceptual, cognitive, and speech symptoms, including Ganser-like state, to a degree not previously possible in such cases.  相似文献   
284.
How do stimulus size and item number relate to the magnitude and direction of error on center estimation and line cancellation tests? How might this relationship inform theories concerning spatial neglect? These questions were addressed by testing twenty patients with right hemisphere lesions, eleven with left hemisphere lesions and eleven normal control subjects on multiple versions of center estimation and line cancellation tests. Patients who made large errors on these tests also demonstrated an optimal or pivotal stimulus value, i.e., a particular size center estimation test or number of lines on cancellation that either minimized error magnitude relative to other size stimuli (optimal) or marked the boundary between normal and abnormal performance (pivotal). Patients with right hemisphere lesions made increasingly greater errors on the center estimation test as stimuli were both larger and smaller than the optimal value, whereas those with left hemisphere lesions made greater errors as stimuli were smaller than a pivotal value. In normal subjects, the direction of errors on center estimation stimuli shifted from the right of true center to the left as stimuli decreased in size (i.e., the crossover effect). Right hemisphere lesions exaggerated this effect, whereas left hemisphere lesions diminished and possibly reversed the direction of crossover. Error direction did not change as a function of stimulus value on cancellation tests. The demonstration of optimal and pivotal stimulus values indicates that performances on center estimation and cancellation tests in neglect are only relative to the stimuli used. In light of other studies, our findings indicate that patients with spatial neglect grossly overestimate the size of small stimuli and underestimate the size of large stimuli, that crossover represents an “apparent” shift in error direction that actually results from normally occurring errors in size perception, and that the left hemisphere is specialized for one aspect of size estimation, whereas the right performs dual roles.  相似文献   
285.
286.
A field experiment was conducted in which a single male, a single female, or a male-female couple attempted to hitch rides at four different traffic locations, under conditions in which the hitchhikers either stared at or looked away from oncoming drivers. It was found that staring increased the probability of a driver stopping from .03 to .067 (z = 2.96, p = .003). The female was a more successful hitchhiker than either the male or the couple, (z = 2.215, p = .026; z = 1.861, p .063, respectively).  相似文献   
287.
A demonstration of cell-specific patterns of development in the immature CNS is provided by examples of characteristic, cellspecific time-courses of enzyme development in different classes of brain cells isolated in highly purified form by bulk-separation from the cerebral and cerebellar cortex of the growing rat. The enzymatic analysis was carried out at the level of the nerve and glial cell lysosomes and mitochondria, two subcellular organelles crucial to the economy of all cells. The findings reveal rather similar developmental patterns for the lysosomal hydrolase N-acetyl-β-D-glucosaminidase in neurons and glial cells of the cerebral cortex as well as in two different cerebellar nerve cell types, the Purkinje and the granule cell. However, significant differences in the post-natal chronology of development of the mitochondrial enzyme α-glycerophosphate dehydrogenase were noted between cortical nerve and glial cells, the glial enzyme exhibiting 6-fold higher levels of activity than the neuronal one throughout the first month of postnatal life. The findings emphasize the feasibility as well as the necessity of studies aimed at the elucidation of the cell-specific aspects of the biochemistry of developing nerve and glial cells.  相似文献   
288.
Data in the literature indicate that conditioned responses (CRs) generated by repeated pairing of conditional stimulus (CS) with administration of a neurotropic drug may resemble its unconditional effects or they may be opposite in direction; furthermore, the CRs may change as such pairings are continued. In explanation, it is hypothesized that as in conditioning of physiological reflexes, a CS repeatedly paired with administration of a neurotropic drug eventually comes to activate central“processing” events that are evoked by the“stimulus” properties of the drug,i.e., the effects of the drug at receptor sites inside or outside the pia mater which lie in the afferent arms of“reflex” neural circuits; or, the CS comes to activate central processing events that are evoked by centripetal feedback responses to the effects of the drug at receptor sites in the processing or efferent arms of reflex neural circuits. Depending on the receptor site action of the drug, the conditioned autonomic and/or neuromuscular responses that are observed may be in the same direction as, or opposite in direction to the unconditioned effects of the drug. With continued pairings of CS and drug, the unconditioned processing events evoked by the stimulus properties of the drug, and hence the CRs also, change in consequence of compensatory (sometimes“overshooting”) biochemical alterations proximal to the receptor site of action of the drug, induced by negative or positive neuronal feedback mechanisms. These concepts are utilized in a theory of opiate addiction and relapse.  相似文献   
289.
The continuum of solutions constituting the bargaining set for n-person games in characteristic function form (n ≥ 4) reflects various degrees of determinateness to form a coalition, different requirements of stability, or different levels of competition among the players. At one end of this continuum is the kernel solution. A new solution, called the competitive bargaining set, constitutes the other extreme. It incorporates the concept of a multiobjection, which is based on the idea that threats may be perceived and considered simultaneously even though their simultaneous implementation is impossible.For the simple homogeneous majority games [n ? 2, 1, 1, …, 1] the competitive bargaining set (1) yields unique outcomes for each coalition structure, (2) coincides with von Neumann and Morgenstern's main simple solution for certain coalition structures, and (3) converges to Shapley value as n → ∞ when the grand coalition forms.Mathematical and experimental implications of the new solution are discussed briefly.  相似文献   
290.
The purpose of this research was to determine the specific behaviors and cues which 104 assessors perceived as indicating the presence of psychological variables shown to be related to competent job behavior. The cue systems utilized were found to be reminiscent of theory Y conceptions of effective job behavior. Implications of the lack of correlation of cue utilization with assessor characteristics are discussed.  相似文献   
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