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941.
L C Drickamer 《Journal of comparative psychology (Washington, D.C. : 1983)》1985,99(4):411-419
Five experiments were performed to investigate the effects of social status in groups of female mice on reproduction and on the release or urinary chemosignals that accelerate or delay the onset of sexual maturation in young females. Treatment of young female mice with urine from bottom-ranking mice in groups of 5 adult females resulted in delays in puberty comparable to those produced by treatment with urine pooled from females housed at moderate to high densities. Treatment of young females with urine from top-ranking females from the same groups resulted in ages for puberty not different from those of control females treated with water. There was an interaction between the social rank of a female and the stages of the estrous cycle with respect to the presence in the urine of chemosignals from grouping that delay puberty and estrus that accelerate puberty. Within groups of 5 adult mice, top-ranking females were in estrus more frequently than bottom-ranking females. Individually caged adult females treated with urine from top-ranking females were in estrus more frequently than females treated with urine from bottom-ranking females. When grouped females were separated into individual cages and mated, there was differential reproductive success: More top-ranking females conceived and bore litters than bottom-ranking females. Bottom-ranking females produced more female pups, relative to top- and middle-ranking females. 相似文献
942.
943.
Paul C. Quinn B. R. Wooten Evette J. Ludman 《Attention, perception & psychophysics》1985,37(3):198-204
Sternheim and Boynton’s (1966) continuous judgmental color-naming technique was used to assess the elemental nature of achromatic colors. Results from three subjects indicate that the names “black” and “white” are necessary and sufficient to describe achromatic test lights associated with the name “gray.” On the basis of the criteria that establishes a color as elemental, black and white were confirmed as elemental, whereas gray was not. These findings support the assumption of various opponent processing models that there are only two elemental achromatic sensations. In addition, the results support Hering’s (1920) view that black and white differ from the paired-chromatic opponent colors in that they are not mutually exclusive. 相似文献
944.
Carl E. Granrud Robert J. Haake Albert Yonas 《Attention, perception & psychophysics》1985,37(5):459-466
Two experiments investigated infants’ sensitivity to familiar size as information for the distances of objects with which they had had only brief experience. Each experiment had two phases: a familiarization phase and a test phase. During the familiarization phase, the infant played with a pair of different-sized objects for 10 min. During the test phase, a pair of objects, identical to those seen in the familiarization phase but now equal in size, were presented to the infant at a fixed distance under monocular or binocular viewing conditions. In the test phase of Experiment 1, 7-month-old infants viewing the objects monocularly showed a significant preference to reach for the object that resembled the smaller object in the familiarization phase. Seven-month-old infants in the binocular viewing condition reached equally to the two test phase objects. These results indicate that, in the monocular condition, the 7-month-olds used knowledge about the objects’ sizes, acquired during the familiarization phase, to perceive distance from the test objects’ visual angles, and that they reached preferentially for the apparently nearer object. The lack of a reaching preference in the binocular condition rules out interpretations of the results not based on the objects’ perceived distances. The results, therefore, indicate that 7-month-old infants can use memory to mediate spatial perception. The implications of this finding for the debate between direct and indirect theories of visual perception are discussed. In the test phase of Experiment 2,5-month-old infants viewing the objects monocularly showed no reaching preference. These infants, therefore, showed no evidence of sensitivity to familiar size as distance information. 相似文献
945.
946.
E J Simburg 《Journal of the American Psychoanalytic Association》1985,33(1):117-132
A small informal poll of local colleagues revealed that despite their interest in the subject, many had doubts about the possibility of analyzing persons aged sixty or over successfully. Their specific questions are collated and are offered as a sample of the questions in the minds of many analysts everywhere. Selected material from the ongoing analysis of a sixty-four-year-old patient is presented that bears on some of the questions raised. In addition, changes in the patient are noted. These are discussed in terms of changes in function, which are equated with structural change. The major thrust of the paper is that development continues throughout the life course, and that the criteria for analyzability remain constant. The chronological age of the adult by itself is not an indicator of eligibility or of suitability for psychoanalysis. 相似文献
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948.
949.
950.
Dieting and binging. A causal analysis 总被引:16,自引:0,他引:16