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41.
This case study concerns an 18-year-old bilingual girl who suffered a radiation lesion in the left (dominant) thalamic and temporal region when she was 4 years old. Language and memory assessment revealed deficits in auditory short-term memory, auditory word comprehension, nonword repetition, syntactic processing, word fluency, and confrontation naming tasks. Both languages (English and Dutch) were found to be affected in a similar manner, despite the fact that one language (English) was acquired before and the other (Dutch) after the period of lesion onset. Most of the deficits appear to be related to verbal (short-term) memory dysfunction. Several hypotheses of subcortical involvement in memory processes are discussed with reference to existing theories in this area. 相似文献
42.
Transparent layer constancy 总被引:1,自引:0,他引:1
W Gerbino C I Stultiens J M Troost C M de Weert 《Journal of experimental psychology. Human perception and performance》1990,16(1):3-20
Perceived transparency was studied as a constancy problem. In the episcotister (E-) model of scission, luminances are partitioned into layer and background components; four luminances determine values of two layer parameters that specify constancy of a transparent layer on different backgrounds. The E-model was tested in an experiment in which 12 Ss matched 24 pairs of four-luminance patterns by adjusting two luminances of the comparison pattern. Both the standard and the comparison were perceived as a transparent layer on a checkerboard. The E-model predicts matches when layer values are identical in the two patterns. One parameter was constant, constraining the adjustment along the second dimension. Obtained values corresponded well with E-predictions. Alternative models based on local luminance or average contrast ratios accounted for less variability. Results indicate that transparency models should utilize luminance, not reflectance, as the independent variable. 相似文献
43.
44.
Molecular sequence data, made available in the last 15 years or so, have led to the classification of living cells into three phylogenetic domains: Bacteria, Archaea, and Eucarya. All the organisms that have been tested belonging to either domain were capable of mounting a stress response with essentially the same characteristics, regardless of the stressor. The protagonists in the cell's stress response are the stress genes and their protein products. Some of the latter are molecular chaperones. Under physiological conditions, these chaperones aid other cellular proteins to fold properly and achieve a native -functional- configuration, and to translocate from the place of synthesis to the cell's locale in which they will operate. In a stressed cell, the stress proteins that are chaperones protect other molecules from denaturation and help those partially damaged to regain a functional configuration. Thus, cell death is avoided and recovery is enhanced. The study of stress genes and proteins has progressed considerably in organisms belonging to the domains Bacteria and Eucarya. Less is known about the archaeal stress genes. Here, research with an organism from the Archaea is discussed, focusing on the stress genes of the hsp70 (dnaK) locus. Future perspectives for basic and applied research within the health sciences and biotechnology industries are presented. 相似文献
45.
W. M. de Muynck 《Synthese》1995,102(2):293-318
The axiomatic approaches of quantum mechanics and relativity theory are compared with approaches in which the theories are thought to describe readings of certain measurement operations. The usual axioms are shown to correspond with classes of ideal measurements. The necessity is discussed of generalizing the formalisms of both quantum mechanics and relativity theory so as to encompass more realistic nonideal measurements. It is argued that this generalization favours an empiricist interpretation of the mathematical formalisms over a realist one. 相似文献
46.
47.
Peter Suedfeld Brian de Vries Susan Bluck Alistair B. C. Wallbaum Paul W. Schmidt 《International journal of psychology》1996,31(5):177-190
Although there are measurable differences in integrative complexity among solutions that individuals generate in dealing with problems, it is uncertain to what extent people comprehend, recognize, and have preferences among different levels of complexity. Integrative complexity is a function of differentiation (the perception of several attributes within, or perspectives about, a topic) and integration (combining the differentiated characteristics in an interactive or synthesizing solution). The current paper reports two experiments dealing with how university students perceive, interpret, and choose among solutions differing in complexity. Experiment 1 showed that subjects accurately rated the complexity of described solutions differing along the continuum, but that their assessment of their own responses differed from the results of expert scoring. Their self-estimated complexity was highly correlated with their preferences, and preferred complexity was reliably higher than either expert- or self-assessed complexity of subject-generated solutions. Subjects were able to hypothesize quite accurately about environmental and endogenous factors likely to affect complexity. Experiment 2 found that in response to problem scenarios, solutions selected as being potentially most effective were consistently more complex than solutions that participants considered themselves most likely to use. The idea of complexity seems to be intuitively recognizable and understandable by untrained subjects: They can and do distinguish among problem solutions (self-generated or presented) that vary on that dimension, and are able to assess accurately the effects of relevant variables. Such subjects also share the bias shown by experts in favour of the superiority of more complex approaches. 相似文献
48.
Idsart Kingma Michiel P. de Looze Huub M. Toussaint Hans G. Klijnsma Tom B.M. Bruijnen 《Human movement science》1996,15(6):833-860
In studies related to human movement, linked segment models (LSM's) are often used to quantify forces and torques, generated in body joints. Some LSM's represent only a few body segments. Others, for instance used in studies on the control of whole body movements, include all body segments. As a consequence of the complexity of 3-dimensional (3-D) analyses, most LSM's are restricted to one plane of motion. However, in asymmetric movements this may result in a loss of relevant information. The aim of the current study was to develop and validate a 3-D LSM including all body segments. Braces with markers, attached to all body segments, were used to record the body movements. The validation of the model was accomplished by comparing the measured with the estimated ground reaction force and by comparing the torques at the lumbo-sacral joint that resulted from a bottom-up and a top-down mechanical analysis. For both comparisons, reasonable to good agreement was found. Sources of error that could not be analysed this way, were subjected to an additional sensitivity analysis. It was concluded that the internal validity of the current model is quite satisfactory. 相似文献
49.
影响学习迁移的几个因素的实验研究 总被引:2,自引:0,他引:2
针对前人较多地从学习材料本身的特点或学习者的心理特点出发去孤立地考察对学习迁移的影响这一现象 ,本研究试采用代数运算材料 ,系统地探讨了学习材料的相同要素和学习者概括化认知过程两者之间的内在关系 ,并将相同要素进一步区分为表述形式相似和内在原理相似。旨在对较为复杂的认知学习中迁移的影响因素做更深入的考察。结果表明 :①概括化和相同要素对学习迁移的影响依然存在 ,但需作具体分析。其中 ,前者应成为影响学习迁移的更重要因素。②在学习材料的相同要素中 ,实质上对迁移起作用的是内在原理相似性 ;而表述形式相似性不起主要作用。③概括化因素和内在原理相似性因素之间的交互作用对学习迁移影响极大。 相似文献
50.
René A. De Wijk Wim Vaessen Johannes Heidema E. P. Köster 《Behavior research methods》1996,28(3):383-391
An injection olfactometer for human psychophysical experiments is described. The olfactometer is capable of presenting, either mono- or birhinally, single odorants and binary mixtures. The pulse form of the olfactory stimulus at the exit of the olfactometer approaches a rectangular form, which makes the olfactometer well suited for olfactory reaction time measurements. Since stimulation periods are independent of the subject’s inhalation, time-intensity measurements over prolonged periods of time are possible as well. In the second part of this paper, a new technique is described for the measurement of the stimulus pulse form at the exit of the olfactometer. 相似文献