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751.
Summary The dependence of the subjective vertical (SV, the angle between a subjective vertical line and body median plane) on the gravity vertical (body tilt position, angle ) and on the optical vertical (i.e., a field of parallel lines seen as background to the line to be adjusted) was investigated. The SV was measured under dry and wet conditions at different degrees of body tilt attained in either clockwise (CW) or counterclockwise (CCW) progression.The measured difference in between field-of-lines left and right of the line is smallest at the upright position (=O°) and largest at =150°/165°. All body positions show a -difference between CW and CCW attainment (hysteresis), this too being least at upright and greatest at inverted body positions.These results, and changes of with test time, are discussed relative to the hypothesis that efficiency of the statolith organs decreases with body tilt increase, favouring increase of interference of somatoreceptors and the optical reference.  相似文献   
752.
Retired and emeritus members of APGA answered a survey on their lives in retirement, their recommendations to APGA concerning activities for retired members, their suggestions for training programs in geriatric counseling, and their advice to younger counselors on planning for retirement. The results indicate most retired counselors are financially comfortable and continue to lead happy and productive lives in retirement. In their recommendations the counselors emphasized the need to remain active and stressed the importance of planning well in advance of actual retirement. They had many specific suggestions for APGA programming.  相似文献   
753.
The problem of word ambiguity has generally been overlooked in compiling lists of words measured on various attributes. In this study, rating measures were obtained on the meanings of 387 words, the ambiguity of which had been established empirically. Imagery, age-of-acquisition, concreteness, and familiarity ratings are reported for each meaning, together with an index of meaning dominance. The results suggest that the most dominant meanings tend to be the most imageable, concrete, familiar, and earliest acquired. Generally satisfactory correlations with other norms were obtained.  相似文献   
754.
A simple dc shock-generating device is described. The principle of operation relies upon the mutual inductance effect between the primary and secondary coils of a transformer.  相似文献   
755.
Developments in television technology have made possible new approaches to the study of the role of visual feedback in motor control. In two experiments using a special videodisc recording and playback system, the effects of delaying for 66 msec a subject's view of his own hand during a target-directed movement was investigated. The observed effects of such visually delayed feedback compared to spatially distorted feedback produced by prisms led to three major conclusions: (a) despite the behavioral similarity (overshooting) induced by the two kinds of altered feedback, the role of each in the visual-motor control loop is different; (b) adaptation to and the after effect of the two kinds of altered feedback are based on different control mechanisms (c) the processing and use of visual information in hand control requires less time than previous experiments have indicated.  相似文献   
756.
757.
How maintenance of orientation during locomotion in unfamiliar environments is accomplished was investigated by having subjects walk behind a moving light line (1.12 m/sec) in a dark room and, from a stopping point, numerically estimate direction and distance to the starting point. Two linear distances (5.0–8.4 m) and the angle of direction change (45, 90, and 135 deg) were orthogonally varied as 12 locomotion patterns. Eight high-school students were assigned to each of three conditions, two in which the starting point was invisible, one in which it was visible. In one of the former conditions the subjects counted backwards rapidly during walking. Lower accuracy and longer latency times were found in the counting condition whilst the other two conditions differed only slightly. The results suggested that accurate maintenance of orientation is achieved by recurrent encoding, coordination and decoding of information about direction change and locomotion distance, processes which demand central processing capacity and therefore are interfered with by a concurrent task.  相似文献   
758.
Normative data are presented for Southern black children on two objective personality inventories for children: the Missouri Children's Picture Series (MCPS), a child picture-sorting task, and the Missouri Children's Behavior Checklist (MBCL), a parent rating scale. The MCPS was administered to 615 black children attending public schools in a low socioeconomic area of the southeast United States. Parents returned the MBCL on 437 of the children. Means and standard deviations on eight MCPS personality scales and six MCBL behavior rating scales are presented for black males and females at ages 5 through 16, and effects of age, sex, and various scale intercorrelations are discussed. Results suggest systematic age and sex differences on the various scales for black children that are quite atypical when compared with the MCPS in other samples. Various empirical questions regarding the validity of these instruments when used with Southern black children are raised.  相似文献   
759.
Single letters were presented tachistoscopically in the left or right hemifield to right-handed observers. Superior recognition of letters on the right was found for letters chosen from subsets containing four items, but no differences were found when any letter, or any symmetrical letter, could appear. In a second experiment, the right hemifield advantage was found under conditions requiring the subject to determine the subset only when the subset chosen was appropriate. Results were discussed in terms of the adequacy of language-based explanations of hemifield asymmetries in letter recognition.  相似文献   
760.
The generality of the recognition failure phenomenon was the primary basis for the present research. It was hypothesized that the phenomenon obtains whenever an insufficient degree of compatibility exists between the task demands at recognition and those present during study. Experiments 1 and 2 demonstrated that, despite a recognition task that was incompatible to conditions of encoding, subjects could actively reconstruct aspects of the initial situation, and hence recognition failure was minimized. It was assumed that the stimulus material — categorized word pairs — facilitated this reconstructive process. Experiment 3 was designed specifically to examine further the reconstructive process as well as recognition failure. The results indicated that (a) the nature of this process could be mathematically predicted, and (b) subjects seldom failed to recognize words they recalled. The results of the present study strongly suggest an important boundary condition of the phenomenon of recognition failure. Moreover, Tulving and Wiseman's (1975) quadratic function could not predict accurately the obtained magnitude of recognition failure.  相似文献   
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