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941.
942.
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   
943.
吴永祥  王秉光 《心理学报》1984,17(3):98-103
本文是以大白鼠在三等分迷宫仪中学习防御性条件反应的方法,观察800拉特γ-线对大白鼠学习能力的影响。实验结果表明,大白鼠的学习能力是下降的,其表现为每天学习的正确率低,达到学会标准所需学习次数增加;反应运动时延长;主动躲避反应的出现率降低。 根据受照动物的特点,我们认为:作为判断学习和记忆能力的指标,反应运动时比正确率更好一点。  相似文献   
944.
不同时相日光下颜色的恒常性   总被引:1,自引:0,他引:1  
一、前言 在光源光谱成份改变的条件下,我们周围物体的颜色在眼睛看来保持相对不变,称为颜色恒常性。1807年Thomas Young首先描述了颜色恒常性现象,他指出室内不管是由蜡烛的黄光或火焰的红光来照明的,书页纸仍然看来是白色的。Young认为,外界某一表面的颜色外观,并不完全决定于网膜的红、绿、蓝三种感受器的吸收特性,而也依赖于周围其它物体射入眼睛的光通量。此后,E.Hering对颜色恒常性做了实验表演。一般认为颜色恒常性是对环境照明感受性的降低。视觉通道只传递由物体表面所反射的光谱成  相似文献   
945.
本工作研究两例先天性无痛症患者的心理特点,主要是其情绪特点,以探讨疼痛和情绪的关系,并借以检验疼痛学说的意义。例一,女,10岁,智力略低于正常,艾森克少年儿童人格问卷表评定人格正常。与身体损伤有关的恐惧感明显缺乏,但与社会和教育影响有联系的恐惧感却甚于正常儿童。情绪急躁,易发作暴发性脾气而不能控制。在突然刺激(强光、强铃声)下的反应和正常儿童相近。例二,男,13岁,智力明显落后,人格评定正常,各种恐惧感均明显缺乏。情绪经常呈明显欣快状态。突然刺激下有口语惊吓和动作反应但无相应的面部表情和植物性神经系统的变化。两例均有无目的的多动作表现。看来疼痛和情绪有某种关系,但本结果并不能证实疼痛的情绪学说。  相似文献   
946.
947.
This paper discusses an exploratory investigation concerned with the long range questions: How does group psychotherapy help patients? and How can psychiatry residency programs best train residents to treat patients in therapeutic groups? Group psychotherapy has come to be accepted in its own right as a decisive contribution to the study of and relief of emotional disorders. As a component of comprehensive psychiatric services it is indispensable. However, while its clinical value has been demonstrated, its scientific validity has not. A Group Process Inventory has been developed by the author and has been utilized for the past two years by psychiatric residents in recording the process of their therapeutic groups in a teaching hospital mental hygiene clinic. The preliminary use of this recording as a clinical-teaching instrument has proven effective. This inventory is being revised to serve as a research instrument.  相似文献   
948.
949.
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   
950.
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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