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991.
Three experiments with rats (Rattus norvegicus) were conducted to examine the roles of the male's penile spines and penile cups (flaring of the distal glans) in the induction of luteal activity in the female, and in the removal of copulatory plugs from the vaginal tract. The results of Experiment 1 revealed no role for the cup in luteal induction but did suggest that elements of the ejaculatory reflex apart from cup formation contribute to the elicitation of this neuroendocrine response. The origin of this stimulatory effect was not directly determined, but indirect evidence suggested a role for penile spines. In Experiments 2 and 3, features of the glans penis that might help effect plug removal were investigated, and the experiments demonstrated that penile spines, perhaps in conjunction with penile cups, contribute to the extraction of plugs from the vagina.  相似文献   
992.
In a behavioral view, the purposes of science are primarily prediction and control. To the extent that a scientist embraces both of these as a unified and generally applicable criterion for science, certain philosophical and theoretical practices are counterproductive, including mentalism in both its metaphysical and metatheoretical forms. It is possible and often worthwhile to recast some mentalistic talk into an issue of behavior-behavior relations. When behavior-behavior relations are approached non-mechanistically, however, analysis cannot stop at the level of the relations themselves. Several analytic concepts common in the behavioral community share some of the dangers of mentalism if not employed properly, including such concepts as self-reinforcement, response-produced stimulation, and self-rules.  相似文献   
993.
To what extent does the reader integrate visual information from one fixation to the next and derive a spatially extended representation of text? Experimental studies of transsaccadic fusion in reading produce conflicting evidence. The results from work on “stepped-text” presentation, in which words appear in a single physical location, have been used to argue that readers secure no advantage from the spatially extended page and that reading may proceed without the computation of spatial coordinates. It is suggested that this conclusion may be inaccurate. A processing decrement is found for materials above a critical level of complexity when presented in a “stepped” mode. This appears to derive from the reader’s need at times to reinspect parts of previously presented text. Reinspections of this kind, which appear to characterize the fluent reader, demand a degree of spatial coding. Two classical issues in the study of perception come together in the study of reading. First, what segments the continuous stimulus flux into discrete perceptible objects? The second is, what is the nature of the control system for eye movements? - Kolers (1983) This research is supported by a grant from the Economic and Social Research Council.  相似文献   
994.
Inpatient Multimodal Therapy (imt) is a residential treatment program, lasting a maximum of 36 weeks, for patients with severe neurotic symptoms. A group of 44 chronic obsessive-compulsive patients and a group of 40 chronic phobic patients were treated in order to assess the outcome and the process of treatment and to identify prognostic factors associated with the effect. At follow-up—on average, eight months after discharge—it was found that 60% had improved, 32% had remained the same, and 8% had deteriorated, indicating that, in general, the treatment was beneficial. That these effects were long-lasting is supported by the fact that, at follow-up, 78% of all patients were no longer receiving treatment, 18% were receiving outpatient or day treatment, and 4% were receiving inpatient treatment. Phobic patients appear to have gained more from the multimodal approach than did obsessive-compulsive patients, as indicated by the fact that the severity of symptoms decreased as they improved in rational thinking, assertiveness, and arousal. By contrast, obsessive-compulsive patients relapsed more than phobic patients did. This was attributed to the fact that the former gained less from the rational-emotive training, denied problems with assertiveness, and did not practice the acquired relaxation skills. It further appeared that a favorable outcome could be induced in patients who (1) expressed relatively mild symptoms in this otherwise severe group, (2) reported relatively few additional complaints, (3) could clearly indicate interpersonal problems, and (4) did not use psychotropic drugs. These prognostic factors are so widespread that not much weight can be ascribed to them. Yet they are useful for indication ofimt until better predictors are found.  相似文献   
995.
The increasing focus on information technology has led to widespread growth in the use of microcomputer systems in counselling settings. While many applications depend on expensive and sophisticated equipment, the humble home computer has many facilities to offer. High resolution graphics and versatile control interfacing, designed for games use, enable easy adaptation to tasks such as visual presentation of biofeedback with the facility for data retention and analysis. A pilot system based on the Commodore 64 is described.  相似文献   
996.
The factors perceived as helpful by members of three different types of self-help groups are examined, using the 12 factors identified by Yalom as operative in group psychotherapy. Questionnaires were given to 45 members of self-help groups, asking for their views of the most and least helpful aspects of their experiences of their group, and for their judgement of its effectiveness. Results indicated that members of a group concerned with social and personal support in the face of a socially problematic situation (widowhood) found the experience of Universality to be the most helpful factor, while Self-Disclosure was least helpful. Members from a group for the physically sick (asthma sufferers) also reported the least helpful factor to be Self-Disclosure, but said that the most helpful factor was Guidance. By contrast, the group concerned with providing 'therapy' for depressives reported Cohesiveness to be most helpful, and Guidance to be least helpful. Comparison with other studies using similar methodologies with different group populations suggests that the factors likely to be effective in self-help groups for the socially unsupported and physically sick on the one hand, and for the psychologically disturbed on the other, may differ.  相似文献   
997.
A study is reported which shows that accommodation can be stimulated by a blur stimulus which is below the threshold for visual perception. It is also shown that perceptual fading of the target, caused by stabilization of the retinal image (Troxler phenomenon), can eliminate the accommodative response causing it to default to its resting level. The first finding suggests a way in which the visual system can filter the percept of blur out of our conscious awareness and still effectively utilize the blur as a steady-state error for the accommodative control system. The second finding is consistent with a locus for the Troxler phenomenon in the early afferent part of the visual pathway, ie the retinal ganglion cells.  相似文献   
998.
Adaptation and reaction-time techniques were used to examine the role of different spatial-frequency channels in the perception of local and global structure. Subjects were shown figures consisting of a large C composed of smaller Cs and asked to identify the orientation of either the global C or its local elements. Prior to performing the task subjects were adapted to different spatial frequencies and the effect on subsequent performance was assessed. Two main results were found. First, the adapting frequency that most affected the global task was often lower than that most affecting the local task, suggesting that high and low frequencies independently code the structure of an image. Second, reaction time to global figures was often faster than to local figures at all levels of detectability, again suggesting a role of low-frequency channels in global processing.  相似文献   
999.
Summary Simple motor responses of different similarity were assigned to geometric figures of different similarity. Subsequently, subjects had to learn hierarchical classifications of visually similar or dissimilar figures which were associated with either similar or dissimilar responses. In this way, the visual and the functional similarity of the conceptually united figures were orthogonally varied. It was found that visually similar figures are conceptually classified fastest regardless of their functional similarity. In contrast, functional similarity has a considerable impact on the hierarchical classification of visually dissimilar figures. Functionally similar figures are conceptually faster classified than dissimilar ones. From the results we conclude that concepts are autonomously formed as mediating representations in stimulus-response coordinations. The hierarchical organization of concepts is thereby based on the sequential organization of both the visual input and the behavioral output. Further consequences of this approach are discussed.Portions of this research were presented at the International Symposium on Structure and Function of Human Memory, in Memoriam Hermann Ebbinghaus, Berlin, July 1985  相似文献   
1000.
Summary Subjects were shown eight-letter pseudowords tachistoscopically and were asked to report as many letters as possible. The pseudowords, examples of either first- or fourth-order approximation to English, were printed in normal or reversed spelling and were presented in either normal of mirror-imaged letters. Finally subjects were either free to report in any order they wished, or they were instructed to report from left to right or from right to left. With normal letters, the familiarity effect was controlled by the spelling direction, not by the direction of report or the match between direction of report and spelling direction. With mirrored letters, however, order of approximation to English had no effect. The results contradict two existing theories: Mewhort's theory claims that the familiarity of fourth-order materials aids processing at a postcategorical level; it has trouble explaining why the familiarity effect disappeared with mirrored letters and normal spelling. Wolff's theory claims that familiarity aids processing at the feature level; it has trouble explaining why the familiarity effect disappeared with mirrored letters and reversed spelling.  相似文献   
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