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181.
The relationship between the Fourier spectra of visual textures (represented by four hypothetical visual channels sensitive to spatial frequencies) and the perceptual appearance of the textures was investigated. Thirty textures were synthesized by combining various spatial frequencies of different amplitudes. Twenty subjects grouped the textures into 2, 3, 4, and 5 groups based on the similarity of their appearance. The groupings were analyzed by means of linear discriminant analysis using the activity of the four channels as predictor variables. The groupings were also examined by multidimensional scaling, and the resulting stimulus configuration was canonically correlated with the channel activity. The results of both analyses indicate a strong relationship between the perceptual appearance of the textures and their Fourier spectra. These findings suport a multiple-channel spatial-frequency model of perception.  相似文献   
182.
A model of childhood hyperkinesis, using the Telomian-beagle hybrid dog, is described, demonstrating the interactions of genetics and separation in the development of this syndrome and in the favorable responses of some of these dogs to amphetamine. This work represents the collaboration of three laboratories, utilizing chiefly methods of inhibitory training. Inducing separation distress enhanced the resistance to inhibitory training and the favorable responses to amphetamine.  相似文献   
183.
A questionnaire completed by 1282 male life insurance agency managers from 50 companies was used to develop (via factor analysis) six behavorial functions of agency managers. The relationship between the frequency of activity in each function and five variables–number of agents, number of supervisors, tenure, type of agency and origin of agency–was examined using zero order and multiple correlation procedures. The two measures of size, number of agents and number of supervisors, were the most consistent correlates of behavior. The degree of shared variance among management functions and the five variables, though significant statistically, did not exceed 9%. Reasons cited for these results included: (1) policies and practices particular to individual companies; (2) the discretion managers have in choosing task activities; (3) the limited number of variables examined as correlates of managerial functions; and, (4) individual differences among agency managers. It was concluded, for practical reasons, that management research should include efforts to develop taxonomies that cut across technological categories of managers as well as defining the specific behavior functions of managers in particular technological categories. Such specific taxonomies are required for effective human resource management practices at managerial levels in organizations.  相似文献   
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185.
An information processing system for a psychiatric emergency room is described. Several studies are presented that show the utility of the system. In the first study, variables involved in diagnosis are explicated. The second study attempts to determine the characteristics that distinguish recidivists from nonrecidivists at an emergency room. The third study attempts to find patient variables related to success in short-term treatment programs. The final study is aimed at discovering whether there are psychopathological effects related to the use of inhalants. Together, these studies show the potential of a mental health information system for learning more about the nature of mental disorders and their treatment.  相似文献   
186.
Human contrast sensitivity is known to vary with both stimulus spatial frequency and orientation. Previous research has indicated, however, that the apparent contrast of a sinusoidal grating is independent of spatial frequency at suprathreshold levels. We have found that the apparent contrast of suprathreshold gratings is not independent of its orientation. Observers adjusted the apparent contrasts of vertical and oblique gratings to match a 40% standard. Contrast match deviations were found at a number of spatial frequencies, indicating a lack of contrast constancy with stimulus orientation. The apparent contrast of gratings in different orientations could not be predicted in any simple fashion from either contrast threshold differences or ratios.  相似文献   
187.
Using an adjustment procedure, human observers matched the apparent spatial frequencies of sinusoidal gratings presented in different orientations (0, 45, 90, and 135 deg). Matches were made between all possible pairwise orientation combinations. Significant match deviations indicated that the apparent frequency of a grating depends on its orientation. The most consistent deviations were found between horizontal and vertical gratings, with horizontal gratings appearing to be of a lower spatial frequency than vertical gratings. These effects were relatively independent of stimulus contrast and persisted when the optics of the eye were bypassed with laser interferometry. A neurophysiological explanation of these effects is proposed.  相似文献   
188.
The Rokeach Dogmatism Scale and the Eysenck Personality Questionnaire were correlated with educator-reported use of corporal punishment. Respondents were from a medium-size school system in Tennessee. Results indicated that closed-mindedness, as measured by the Rokeach scale, and Neuroticism, as measured by the Eysenck Scale, were highly correlated with reported use of corporal punishment. Of the remaining two dimensions of personality measured by the Eysenck questionnaire, Extraversion was found to be moderately correlated with reported use of corporal punishment while Psychoticism showed no significant relationship. A significant negative correlation was found between years of experience in teaching and use of corporal punishment. Frequency of physical punishment used on an educator when he/she was in grades K-12 was positively correlated with reported use of corporal punishment. Heavy users of corporal punishment tended to be relatively inexperienced, close-minded, neurotic, and impulsive as compared to their peers who did not use corporal punishment.  相似文献   
189.
The behavioral effects of d-amphetamine sulfate were studied in adult male stumptail macaques living within a large heterogeneous group in an outdoor enclosure. Among five subjects that received a range of doses (.01 to .3 mg/kg), d-amphetamine increased self-aggressive behavior and abnormal posturing in subjects that exhibited these types of behavior prior to drug administration, but it had no effect in subjects not exhibiting those activities in the absence of the drug. For the former subjects, the dose-effect curves for self-aggression were of an inverted U-shape analogous to the effect of d-amphetamine on schedule-controlled behavior. Over the range of doses studied, the curve for abnormal posturing was monotonic. The data indicate that d-amphetamine can have effects on untrained behavior in individual animals in a quasinatural environment that are qualitatively and quantitatively similar to the behavioral effects observed in other laboratory environments, and that d-amphetamine does not evoke or increase a behavioral response in individual subjects that do not exhibit the response in the absence of the drug.  相似文献   
190.
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