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871.
Two adult male chimpanzees reached through a hole in the wall of their home cage and, by tracking the images of their hands and of an otherwise hidden target object in a mirror or closed-circuit television picture, moved their hands in whichever direction was necessary to make contact with the target object. They discriminated between live video images and tapes and performed effectively when the target objects were presented in novel locations and when the video picture was presented at random in different orientations. There was thus no consistent relation between the location of images on the monitor and the location of their real-world counterparts. Comparable performances in monkeys and nonprimates seem unlikely.  相似文献   
872.
Bornstein’s hypothesis that there is a loss of color discrimination in tropical areas was not supported in earlier research in the Cook Islands. Using a more sensitive color vision test (the Farnsworth-Munsell 100-Hue Test), a loss of color discrimination in the red-purple and blue-green regions of the spectrum was found. The lack of sex differences in this color discrimination loss supports a physiological rather than a genetic explanation of the observed decrement.  相似文献   
873.
874.
Due to the death of a severely disabled infant from Bloomington, Indiana, a series of events set in motion by the U.S. Department of Health and Human Services has resulted in cautions to health care providers. The resulting policies and procedures warn hospital personnel against withholding nutritional sustenance or medical treatment from severely disabled infants. This article presents dimensions that might serve as a background for counselors to assist families in considering options related to disabled infants. These dimensions include the meaning of life, cost to benefit ratio, medical options, legal precedent, and a theological perspective. This issue is related to counseling practice through counselor ethics, values, and the need for information that counselors can provide to parents during the decision process.  相似文献   
875.
Catastrophe theory is a new mathematical science that permits some insight into the way in which sudden changes or discontinuities of behavior may occur even though the underlying causative forces are essentially continuous. This article aims to present a nonmathematician’s view of catastrophe applications in clinical psychology. Areas covered include anorexia nervosa, binge eating and drinking, affective disorders, schizophrenia, aggressiveness, and prison disturbances. Where appropriate, therapeutic implications and possible physiological correlates are offered. Examples are given of catastrophe theory’s ability to explain previously inexplicable findings. Attention is drawn to its refutability and predictive value, and hence its scientific respectability.  相似文献   
876.
Two experiments investigated whether the initial organization of ambiguous pictures presented supraliminally could be influenced by the presentation of semantically related pictures that had been pattern masked to prevent conscious representation. Twenty-two pictures were presented tachistoscopically in a counterbalanced sequence, each alternating with the supraliminal presentation of its ambiguous counterpart. The results supported the hypothesis that pictures precluded from consciousness by pattern masking could nevertheless influence the interpretation of ambiguous pictures. Although the possibility of structural priming could not be completely ruled out in these experiments, there is evidence to suggest that semantic priming is a component. The research potential of semantic priming is also discussed.  相似文献   
877.
878.
This article reports the results of 629 subjects in three experiments designed to replicate and extend the phenomenon of vicarious verbal conditioning. Experiment I replicated the finding that subjects who responded most to vicarious verbal conditioning were aware of the contingency involved. Experiment II attempted to examine the effects of prior history with the verbal reinforcer on vicarious verbal conditioning by providing seven groups of subjects with varying classic conditioning histories prior to vicarious verbal conditioning. The null results associated with this experiment were hypothesized to be due to the fact that the vicarious verbal conditioning took place in a language laboratory where the subjects could hear but not see the model. Experiment III replicated Experiment II in a live group context as was done in Experiment I. The results showed a) that vicarious verbal conditioning was again found to take place, b) that associating the verbal reinforcer with a tone or tone plus money via forward classic conditioning potentiated the effects of the verbal reinforcer, c) that backward classic conditioning did not potentiate the reinforcer, d) nor did either of two sensitization procedures potentiate the effects of the verbal reinforcer. Both aware and unaware subjects evidenced vicarious verbal conditioning.  相似文献   
879.
Five- and 7-month-old infants were tested for sensitivity to the depth cue of shading. Infants were presented with two displays: a surface in which a convexity and a concavity were molded and a photograph in which shading specified a convexity and a concavity. Each display was presented under both monocular and binocular viewing conditions. Reaching was observed as the dependent measure. Infants in both age groups reached preferentially for the actual convexity in both the monocular and binocular viewing conditions. In the monocular photograph condition, the 7-month-olds reached preferentially for the apparent convexity specified by shading, indicating that they perceived it to be an actual convexity. These infants showed no significant reaching preference in the binocular photograph condition. This finding rules out interpretations of the infants’ reaching not based on perceived depth. The results therefore suggest that the 7-month-olds perceived depth from shading. The 5-month-olds showed no significant reaching preferences when viewing the photograph; thus, they showed no evidence of depth perception from shading. These findings are consistent with the results of a number of studies that have investigated infants’ sensitivity to pictorial depth cues. Together, these studies suggest that the ability to perceive depth from pictorial cues may first develop between 5 and 7 months of age.  相似文献   
880.
This research was designed to compare time judgments obtained under prospective conditions (in which subjects are instructed to attend to time) and retrospective conditions (in which subjects are unaware that they will be required to judge time). In Experiment 1, subjects prospectively or retrospectively judged the duration of intervals spent performing a perceptual-motor task at different levels of difficulty. The results showed that subjects tested under both research paradigms tended to give increasingly shorter and/or more inaccurate time judgments with increases in nontemporal task demands. Experiment 2 was designed to test the effects of attentional deployment on perceived time by comparing prospective and retrospective judgments under control, selective attention, and divided attention conditions. Both types of time judgments became increasingly inaccurate as attention was more broadly deployed. The results of these experiments are consistent with an attentional allocation model, and they suggest that nontemporal task demands disrupt or interfere with timing in both prospective and retrospective situations.  相似文献   
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