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851.
When a figure moves behind a narrow aperture in an opaque surface, if it is perceived as a figure, its shape will often appear distorted. Under such anorthoscopic conditions, the speed or direction of the object's motion is ambiguous. However, when the observer simultaneously tracks a moving target, a figure is always perceived, and its precise shape is a function of the speed or direction of tracking. The figure is seen as moving with the speed or in the direction of the target. Thus, it is argued that eye movement serves as a cue to the figure's motion, which, in turn, determines its perceived length or orientation.  相似文献   
852.
The purpose of this paper is to help clients and others more fully appreciate the complex chain of events intervening between an external happening and an emotional response to that happening. It deals first with the sensory processing of physical stimulation and then presents the current state of knowledge regarding stress psychophysiology. A decision by the cortex which defines something as dangerous or threatening activates two major stress reaction pathways, the endocrine system and the autonomic nervous system, with a large number of physical consequences such as: acceleration of heart rate, increased blood pressure, reduced effectiveness of the immunological system, slowing of gastro-intestinal processes, pupil dilation, bronchial dilation and inhibition of salivation. The complexity and variety of such consequences is illustrated with a series of flow-chart diagrams, and it is suggested that these can be an additional and persuasive argument for the RET position which follows the claim of Epictetus: People are disturbed not by things, but by the views they take of them. Finally it is argued that while rapid emotional responses oftenseem to occur automatically it is because the intervening cortical processes are at times not verbalized. This is shown in the context of a diagrammatic outline of the Rational-Emotive Therapy process.Paul J. Woods, Ph.D., co-editor of this journal, is an associate fellow and an RET training supervisor of the Institute for Rational-Emotive Therapy.  相似文献   
853.
Most of the empirical literature on juvenile homicide has emerged from the clinical experience of mental health professionals who have diagnosed and/or treated youngsters who killed. After a critical review of this literature, data on 787 juvenile homicide offenders are presented and discussed. These data indicate that intrafamilial killings represent but a small fraction of all homicides perpetrated by juveniles and that there are clear differences between intrafamilial and extrafamilial juvenile homicides.  相似文献   
854.
Mediaeval logicians inherited from Boethius an account of conditional propositions and the syllogisms which may be constructed using them. In the following paper it is shown that there are considerable difficulties with Boethius' account which arise from his failure to understand the nature of compound propositions and in particular to provide for their negation. Boethius suggests that there are two different conditions which may be imposed for the truth of a conditional proposition but he really gives no adequate account of how such propositions may be obtained. The true greatness of Peter Abaelard as a philosophical logician is revealed in what he is able to do with the material which he found in Boethius. It is shown that he developed a precise theory of conditionals giving an account of how true conditionals may be obtained and principles which may be used to reject others as false. Unlike Boethius Abaelard properly appreciates that conjunctions must be treated as logical units. Even he, however, falls victim to difficulties which arise when this connective is brought into contact with negation and the conditions which he lays down for the truth of a conditional.  相似文献   
855.
This study compared the predictive validity of two types of overall assessment center ratings (clinical and mechanical) and two types of performance ratings (supervisor and subordinate). Data were gathered on approximately 50 law enforcement agency managers over a four-year time span. Results indicated that clinical predictions were not significantly better than mechanical ones and that prior performance ratings were better predictors of future performance ratings than were assessment centers. Further, dimension ratings within the assessment center were found to be unrelated to ratings of the same dimensions on the job four years later, supporting the notion of subtle criterion contamination (Klimoski & Strickland, 1977) and raising questions about the central assumptions underlying the assessment center approach.  相似文献   
856.
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858.
Operant conditioning and multidimensional scaling procedures were used to study auditory perception of complex sounds in the budgerigar. In a same-different discrimination task, budgerigars learned to discriminate among natural vocal signals. Multidimensional scaling procedures were used to arrange these complex acoustic stimuli in a two-dimensional space reflecting perceptual organization. Results show that budgerigars group vocal stimuli according to functional and acoustical categories. Studies with only contact calls show that birds also make within-category discriminations. The acoustic cues in contact calls most salient to budgerigars appear to be quite complex. There is a suggestion that the sex of the signaler may also be encoded in these calls. The results from budgerigars were compared with the results from humans tested on some of the same sets of complex sounds.  相似文献   
859.
Most knowledge of parent-offspring relations in mammals is derived from studies of mother-infant interactions. Male parental care has been less well studied. We explored maternal and paternal behavior of the California mouse, Peromyscus californicus. Six pairs of parents and their young were videotaped continuously for 12 hours/day, on alternate days from Days 1 to 31 postpartum. Males exhibit all parental activities and to the same extent as displayed by mothers, except lactation. Male parental behavior begins on the day of birth. Mothers and fathers spend substantial and equivalent amounts of time in the nest and in physical contact with pups throughout lactation. Males devote more time than females to licking pups, although females engage in more pup anogenital licking. Mothers nurse for at least 4 weeks, and fathers and mothers both build nests and carry young. The biparental care system of Peromyscus californicus affords an opportunity to develop a broader, more complete view of parent-offspring relations.  相似文献   
860.
Several theories have been presented that predict differences between women and men in attitudes toward the environment due to differences in sex roles. Research on which these theories can be tested has tended to examine general environmental concern, and the results have generally been weak and inconclusive. Using an approach suggested in the literature, this study examines sex differences in concern and knowledge, using multi-item scales for each, about one environmental issue — acid rain. The results contradict the theories being tested, however: if there is a sex difference, men are found to be more concerned and knowledgeable about the environmental problem.  相似文献   
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