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241.
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Dr. Norbert Roth Jutta Beyreiss Klaus Schlenzka Hannelore Beyer 《Journal of abnormal child psychology》1991,19(1):1-13
ADDH children are often reported to display signs of allergies to various substances and/or atopic (AT) symptoms (i.e., atopic eczema, hay fever, or asthma). Since, at least for a subgroup of these children, a common biological background for both ADD and atopy may be assumed that may involve brain catecholamines, our hypothesis was that in a group of AT children (mainly atopic eczema) signs of ADD should appear more often than in controls. Parental hyperactivity ratings revealed a significantly higher frequency of ADD symptoms in the AT group, and laboratory tests sensitive to attentional capacity and inhibitory functions showed poorer performance in the AT children, the findings being similar to those reported in hyperactives. Thus, our results add support to the assumption of a common predisposing factor for both AT and ADDH in a subgroup of children. 相似文献
243.
A standard speaker read linguistically confident and doubtful texts in a confident or doubtful voice. A computer-based acoustic analysis of the four tapes showed that paralinguistic confidence was expressed by increased loudness of voice, rapid rate of speech, and infrequent, short pauses. Under some conditions, higher pitch levels and greater pitch and energy fluctuations in the voice were related to paralinguistic confidence. In a 2 × 2 design, observers perceived and used these cues to attribute confidence and related personality traits to the speaker. Both text and voice cues are related to confidence ratings; in addition, the two types of cue are related to differing personality attributes. 相似文献
244.
In pointing at visual targets without sight of the hand, large errors occur. There is a tendency to overreach targets, and this tendency is much greater (about 25 em) when convergence is the only cue to distance than when there are many cues (2–11 cm). Angular errors of up to 10 deg also occur. These tend to be to the side opposite the sighting eye, when the favored hand is used. The variance of the pointing response with convergence alone is reduced by approximately half with the introduction of several spatial cues. These results are interpreted as indicating that, for a target within the reach of the arm and with convergence alone as a cue, the depth signal produced by the visual system corresponds to a greater distance than that produced when many cues are available. The results are also consistent with the hypothesis that perceived direction tends to approximate direction from the sighting eye. 相似文献
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Klaus Mainzer 《Journal for General Philosophy of Science》1988,19(2):290-307
In spite of their growing specialization, modern natural sciences intend to reduce their theories to some fundamental structures: Physics tries to unify the different physical forces in one fundamental force. Chemistry tries to explain the structure of chemical substances by the quantum mechanics of molecules. Biology tries to reduce the processes of life to biochemical and biophysical laws. Mathematically, the unification of natural science can be described by structures of symmetry, the specialization of science, the variety, and emergence of new phenomena by symmetry breaking. In the following, the successes and lacks of the reductionistic program are shown in recent developments of physics, chemistry, and biology. Philosophical discussions on holism, reductionism, and unification of science can be clarified by structures of symmetry and symmetry breaking. Alternative non-reductionistic view-points are not only possible, but desirable for the lacks in the reductionistic program. Nevertheless, the categorical framework of symmetry and symmetry breaking supports interdisciplinary work and gives new insight in a common structure and theory of natural science. 相似文献
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Alternations of the state of apparent self-motion during observation of a large visual display rotating about the line of sight are associated with alternations in the magnitude of induced tilt and torsional eye rotation. In one experiment, shifts in visually induced tilt during these state alternations are found to be in the opposite direction to corresponding shifts in induced ocular torsion. In a second experiment, the reversals of self-motion perception are shown to be an intravisual phenomenon, independent of competing inputs provided by the vestibular system. These results emphasize the importance of distinguishing between visual and vestibular processes in tilt perception and ocular rotation during human orientation to gravitational vertical. 相似文献
250.
Subjects experienced an illusion of self-motion when viewing the randomly patterned inner surface of a cylinder rotating about their main body axis. This sensation of rotation in a direction opposite to the direction of cylinder rotation is known as circular vection. An experiment was conducted to ascertain if the production of circular vection involved a binocular process in the visual system. Using dichoptic strobe illumination, stimuli were created that were identical monocularly but different binocularly. Groups of normal and stereoblind subjects were tested. The presence of purely binocular (cyclopean) stimulation increased the reported magnitude of vection for both groups. We conclude that a binocular process is involved in the production of circular vection and that this process retains its binocularity in stereoblind subjects. 相似文献