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981.
Summary It is argued that the structure of the Munsell solid is not sufficient to explain the evolution of color terms as Zollinger (1984) has argued. A manifold model of color perception is described with a local metric structure of discriminability and a global categorical structure. This model elucidates the interdependency of the different levels of constraints on color naming and permits the integration of experimental results which cannot be explained in the model underlying Zollinger's (1984) color-metric argument for the emergence of turquoise.  相似文献   
982.
983.
In September 1981, a symposium of distinguished mental health practitioners from various clinical, administrative, research, and legal disciplines was conducted on the topic of “Behavioral Science and the Secret Service,” under the sponsorship of the National Academy of Sciences, Institute of Medicine. The article combines a study of the symposium's written conference summary, the author's experience as legal counsel to a state security hospital, and research into federal cases that have interpreted the so-called “Presidential Threat Statute” (18 USC 871) in order to discuss the role of the Secret Service in protecting elected federal officials from physical harm. The potential for increasing practical cooperation between the Service and state mental health systems is also discussed.  相似文献   
984.
Since the early 1900s a variety of names has been proposed for the scientific study of behavior, but none has come into general use. "Praxics," a recent entry, is defensible on several grounds. "Behaviorism," on the other hand, is the name of a school of philosophy. Though praxics has roots in behaviorism, the term "behaviorism" should not be applied to praxics. Confusion between the science and the philosophy has retarded the growth of the science immeasurably. Its growth has also been impeded by its association with psychology, which is still primarily the study of mind. Efforts are underway to establish praxics as an independent field.  相似文献   
985.
986.
987.
The author focuses on the trend in the family therapy field toward an expanded view of families in the context of their social environments. Within this broader eco-system perspective attention is given to individual-family-social network interrelations with implications for the family therapist.An earlier version of this paper was presented at the American Association for Marriage and Family Therapy, Dallas, Texas, October 29, 1982. Appreciation is expressed to Alice Lynn for her comments and suggestions on an earlier draft of this paper. The author has also benefitted from discussions with Douglas Sprenkle on paradigms and contexts.  相似文献   
988.
989.
The functional significance of learned population differences in male song in the white-crowned sparrow was explored in natural populations using playback tests. Laboratory results have shown that learning of the population-specific song seems to take place in early life and is strongly dependent upon the nature of the auditory experience at that time. However, the varied results of recent studies make it difficult to reach a confident conclusion about the ecological functions of song learning. The present research took advantage of naturally occurring variation in the differences between songs of adjacent populations to determine a function relating degree of difference in song to intensity of territorial singing elicited. Applying a typological evaluation of syllable structure to the four segments of the song allowed a crude quantitative ranking of the differences between local songs and playback stimuli. These results, together with those of other studies, suggest a unimodal aggressive response function of males to songs of other males. A maximum response to songs slightly different from the local song environment suggests that male exclusion based upon acquired song components may contribute to the maintenance of discrete and stable song dialects.  相似文献   
990.
Three experiments are described which elaborate some of the conditions under which rats will contact and manipulate a periodically presented retractable lever. Experiment 1 demonstrated that (i) initial manipulative oral and manual contact with the lever was facilitated if the rat had previous experience of food delivery in the experimental chamber; (ii) persistence in contacting the lever on successive presentations was a function of whether food continued to be presented in the experimental environment; and (iii) food satiation significantly reduced the tendency of the rat to contact the lever even though an expectancy of food had previously been established under conditions of food deprivation. Experiment 2 suggested that the tendency to approach and contact the lever was in part a function of the local moment-to-moment conditional probability of food delivery. Experiment 3 found that the probability of contacting the lever was higher during presentation of an auditory CS signaling a high rate of food delivery than during stimuli signaling no food at all. These results are interpreted as suggesting that the food-signaling aspects of an appetitive CS and that CS's ability to generate signal-directed behaviors are experimentall separable properties.  相似文献   
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