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951.
This article explores the application of the free speech clause of the First Amendment to the purported right of an individual to think socially stigmatized thoughts—for example, psychotic or sexually sadistic thoughts. The state may attempt to control such thoughts either by imposing a thought-control technology on the thinker or by prohibiting the thinker from voluntarily using thought-control technology of his own. Thought-control technologies embrace antipsychotic drugs, hallucinogenic drugs, pornography, and other mind-altering devices. Two underlying models of the free speech clause are proposed—a strong model and a weak model. Despite the apparent endorsement of the strong model by the United States Supreme Court, courts in fact vacillate between the two models and are, apparently, reluctant to utilize the First Amendment as a tool to enforce any right to think wicked thoughts. This reluctance, it is proposed, may well have a religious basis in an equation of wicked thoughts with sin.  相似文献   
952.
Theoretical and technical considerations of measuring puff and inhalation volumes during cigarette smoking are reviewed. Measures of smoking behavior using a flowmeter and inductance plethysmography are described and demonstrated with seven subjects smoking over a 3-to 4-h period. Puff volume and duration, inhaled volume and duration, interpuff and intercigarette interval, and number of puffs varied for each individual over the session. The ratio of puff volume to inhaled volume changed with successive cigarettes. Smokers adjust the concentration of smoke by blending air with the smoke. Thus, to completely characterize smoking behavior, the volume of smoke and air inhaled into the lungs must be measured directly.  相似文献   
953.
Digital music synthesizers represent audio signals in the form of binary coded numbers. These binary coded numbers can be manipulated by the operator, thereby altering the audio signal in a variety of ways. The present article describes how these capabilities can be used to produce perfectly aligned dichotic tapes in which the stimulus items are matched on all extraneous (timbre, amplitude, duration) factors.  相似文献   
954.
The article by Wilcox and Edwards (1982) is discussed in terms of the notion of a Physics necessary for an explanatory theory of Perception. Phenomenological explanations, while true, are rejected as lacking explanatory adequacy. Some examples of succesful computational theories, covering the phenomena Gibson considered basic to an Ecological Physics, are given which are based upon a classical optics.  相似文献   
955.
J T Pardeck  W L Nolden 《Adolescence》1983,18(72):845-850
Through a secondary analysis of existing data, the authors researched the question of what types of aggressive behaviors are learned from an individual's social environment. The findings included data on three student groups: 1) students who had never been in military service; 2) students who had been in military service and had been to Viet Nam; and 3) students who had been in military service, but who had not been to Viet Nam. The results indicated that assault is clearly one aggressive behavior that appears to increase with exposure to an aggressive life experience.  相似文献   
956.
957.
de Silva and Rachman (1981) have recently suggested that although non-reinforced exposure of a fear-evoking stimulus constitutes a sufficient condition for unlearning fears, it does not represent a necessary condition. This conclusion was reached, in part, by examples they provide which appeared to them to suggest that fear-reduction can occur in the absence of exposure to the fear stimulus. They then call for an extended search for non-exposure types of intervention, especially those involving ‘sources of information’ and ‘expectations’. After reviewing in detail the arguments advanced, the present authors adopt the position that de Silva and Rachman's conclusions are premature and unwarranted. To abandon or lose sight of one of the most effective and perhaps most important therapeutic principles, CS exposure, would be myopic and detrimental to the advancement of effective behavior change. At this point in time what is needed is a more careful analysis of the extinction process especially at the stimulus level so the effectiveness of this principle can be maximized.  相似文献   
958.
The role of marking when reward is delayed   总被引:1,自引:0,他引:1  
Two-choice spatial discrimination by rats is enhanced if a salient stimulus marker occurs immediately after every choice response and again after a delay interval (Lieberman, McIntosh & Thomas, 1979). Three experiments further explore this effect. Experiment 1 found that the second marker is unnecessary. Experiment 2 found that a marker presented before a response is as effective as one presented after. Both effects could be explained in terms of markers focusing attention on subsequent cues. Experiment 3, however, found that markers after choice enhance learning even when no discriminative cues are present following the marker. Markers thus appear to initiate both a backward search through memory and attention to subsequent events; both processes help to identify events that might be related to the unexpected marking stimulus.  相似文献   
959.
Three experiments were conducted to examine the relation between response tempo and separable-integral responding. A restricted classification paradigm, in which similarity-based (integral) and dimensionally based (separable) classifications were pitted against one another, was used with the dimensions of length and density (all experiments) and size and brightness (Experiment 3). The subjects were college students (Experiments 1 and 2) and kindergarten, second-, and fifth-grade children (Experiment 3). In all three experiments, rapid responding was associated with fewer dimensional and more similarity responses than was slow responding. This result held when response tempo was simply measured (Experiments 1 and 3) and when it was manipulated by the experimenter (Experiment 2). The results were interpreted to be consistent with models of dimensional processing in which holistic, integral processing precedes analytic dimensional processing.  相似文献   
960.
Three experiments examine the perceptual salience of shading information for the visual specification of three-dimensional form. The observers in these experiments were required to estimate the surface curvature and direction of illumination depicted in computer-synthesized images of cylindrical surfaces, both with and without texture. The results indicate that the shininess of a surface enhances the perception of curvature, but has no effect on perceived direction of illumination; and that shading is generally less effective than texture for depicting surfaces in three dimensions. These and other findings are used to evaluate the psychological validity of several mathematical analyses of shading information that have recently been proposed in the literature.  相似文献   
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