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831.
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   
832.
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   
833.
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   
834.
835.
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   
836.
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   
837.
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   
838.
Twenty elderly subjects (70-90 years old) and 20 young control subjects (18-24 years old) underwent three kinds of olfactory testing: absolute thresholds to three odorants (d-limonene, iso-amyl butyrate, benzaldehyde), magnitude matching of these odorants to salt tastes, and odor identification of 30 common substances. For all three odorants elderly subjects' mean threshold significantly exceeded that of the young by about ninefold for d-limonene, about threefold for benzaldehyde, and about twofold for iso-amyl butyrate. These threshold differences predict approximate concentration differences necessary to arouse the same estimated odor strength above the threshold for the elderly and the young. Young subjects also scored better than the elderly in odor identification, even when subjects were given four alternatives from which to select the correct label. Unimpaired olfactory functioning is uncommon in the elderly; correlational tests show that as a group the young have better olfactory ability and show more interindividual uniformity.  相似文献   
839.
Affect, personality, and facial expressive characteristics of older people   总被引:1,自引:0,他引:1  
This study explored the relationship between emotion-based personality traits and expressive patterns in older subjects. Specifically, the study sought to demonstrate (a) that individuals have emotion expression biases, as revealed by structural and dynamic properties of the face, and (b) that there is a link between facial characteristics (as indexed by the judgments of trained and naive raters) and personality traits. An encoding/decoding paradigm was used; 30 adult, naive judges rated five emotion-pose photographs for each of 14 older subjects who had also completed a personality trait measure. Results indicated that individuals vary in their ability to accurately encode emotion states and that these patterns are linked to personality traits in an affect-specific way. The results are discussed within the framework of Darwinian theory and Plutchik's model of personality.  相似文献   
840.
Elderly subjects were 41% less accurate than young subjects in localizing a point in the frontal plane. The decline could be ascribed neither to an age difference in image formation or skill acquisition nor to a difference in motivational level or trace retention. Evidently the "ambient" or "transient" visual system is compromised at an elementary level. Reasons why this deficit may not be compounded at more complex levels of spatial processing are suggested.  相似文献   
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