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981.
982.
Chronic pain consisting of anesthesia dolorosa secondary to bilateral interruption of the trigeminal nerves is presented as a brain stem reticular denervation syndrome. Electrothalamograms revealed fast frequency discharges in the mesothalamic prerubral and centermedian reticular formation. Mesothalamic electrical stimulation attenuated the discharges. Pain and other symptoms presumably of brainstem origin also were attenuated or abolished by therapeutic electrical stimulation twice daily. It is postulated that brain stem-represented behavioral generators are implicated by the reticular discharges in order to produce the complex symptomatology. Consequently the symptom complex is collectively identified as a brainstem “mini-discharge” syndrome. A theoretical discussion is presented to defend the thesis that reticular denervation-induced low threshold discharge system accounts for the episodic states of pain, dyskinesia, mood, and memory disturbances.  相似文献   
983.
984.
Effects of smoking on spontaneous bilateral skin conductance were studied as a consequence of interactions with set and setting. Bilateral skin conductance was recorded in six men and six women who smoked and an equal number of nonsmokers on two different days. On the first day, spontaneous electrodermal activity was recorded before and after a 10-minute rest period during which half the smokers smoked a cigarette. On the second day, one week later, spontaneous activity was again recorded before and after a 10-minute rest period during which the remaining smokers smoked a cigarette. Nonsmokers did not smoke at any time. Following smoking there was a significant negative correlation between a preference for visual over nonvisual imagery and spontaneous skin conductance responsivity in the left as compared to the right hand. Correlations were significantly different in smokers and nonsmokers. Smokers showed significantly greater preferences for either visual or nonvisual imagery than nonsmokers. Nonresponding nonsmokers were higher on the psychoticism (P) scale of the Eysenck Personality Questionnaire (EPQ) than responding nonsmokers. Smokers scored higher on P than nonsmokers. Interactions between personality, cognitive style, and the experimental situation, set, and setting were discussed in relation to the arousing effects of nicotine.  相似文献   
985.
American psychologists are informed on Pavlov’s work on conditional reflexes but not on the full development of his theory of higher nervous activity. This article shows that Pavlov’s theory of higher nervous activity dealt with concepts that concerned contemporary psychologists. Pavlov used the conditioning of the salivary reflex for methodological purposes. Pavlov’s theory of higher nervous activity encompassed overt behavior, neural processes, and the conscious experience. The strong Darwinian element of Pavlov’s theory, with its stress on the higher organisms’ adaptation, is described. With regard to learning, Pavlov, at the end of his scholarly career, proposed that although all learning involves the formation of associations, the organism’s adaptation to the environment is established through conditioning, but the accumulation of knowledge is established by trial and error.  相似文献   
986.
A questionnaire monitoring occupational aspiration, ethnic identification, adolescent experience, and self-esteem was administered to a large sample of Indian and Anglo-Saxon British male and female adolescents attending school in the West Midlands. The relationship between these variables and differences between the four groups were consistent with predictions derived from the social identity approach to intergroup relations and group behaviour (Tajfel & Turner, 1979). Indian males were found to possess a social mobility belief structure that mediates high occupational aspirations and keeness to marry out of their ethnic group. In contrast, Indian females were found to possess a social change belief structure associated with acceptance of the status quo and lower aspirations. Males and Anglo-Saxons reported higher self-esteem than females or Indians. The adolescent experience findings were less clear, but were consistent with the general interpretation of the data that the differences in intersex relations and gender-related experiences are contingent on ethnicity.  相似文献   
987.
A technique is described in which line-drawn pictures can be rapidly interlaced, allowing for sequential part presentation or tachistoscopic presentation on the Apple II. This is accomplished using a two-stage process in which the pictorial stimuli are converted into machine code data files and then used to create a rapidly changing display consisting of two or more line drawings. The latter stage could be accomplished in less than 2 msec but is limited by the frame time of the monitor (17–20 msec).  相似文献   
988.
989.
990.
T D Fisher 《Adolescence》1986,21(83):517-527
Previous studies indicate that adolescents whose parents talk to them about sex tend to be less sexually active and more likely to use an effective means of contraception. This study sought to determine the relationship between parent-child communication about sex and young adolescents' reproductive and contraceptive knowledge and sexual attitudes. Twenty-two 12- to 14-year-olds and their parents completed sexual-knowledge, sexual-attitude, and contraceptive-choice questionnaires. Families were divided into high-communication and low-communication groups. There were no significant differences in the sexual knowledge, attitudes, or contraceptive choices of the children in the two groups, but the correlation between parents' and children's sexual attitudes in the high-communication group was significantly higher than that of the low-communication group. Although this was a correlational study, it seems likely that the similarity in sexual values was the result of parent-child discussion about sex.  相似文献   
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