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261.
The relationship between amphetamine-induced stereotyped behavior and a neuroendocrine index of arousal, plasma corticosterone (CCS), was investigated. 6-Hydroxydopamine lesions of the caudate-putamen, which produced dopamine depletions of 60%, blocked stereotypy and prolonged the elevation in corticosterone associated with d-amphetamine treatment (5 mg/kg). Similar dopamine depleting lesions of the nucleus accumbens, which attenuated the locomotor, but not the stereotypic, response to AMPH did not have this effect on CCS. This pattern of results supports the hypothesis that stereotypy has a coping function which may serve to alter arousal and further suggests important differences between the nigrostriatal and mesolimbic dopamine projections in modulating the responsiveness of the neuroendocrine system. These results have implications for understanding the function of behavioral stereotypies common to a number of psychopathological conditions, including schizophrenia and childhood autism. 相似文献
262.
The caudal portion of the hypoglossal nucleus (nXIIts) contains the motor neurons that control the syrinx in songbirds. In canaries, song occurs seasonally, is principally produced by males, and appears to be produced predominantly by muscles on the left side of the syrinx. The present study measures the effect of seasonal change and manipulation of testosterone levels on synapse number and morphology in nXIIts in adult female canaries. We find that synapse density is lower in testosterone-treated birds than in control birds and lower in fall than in spring. The number of vesicles per presynaptic profile increases in the spring as a result of a general increase in this measure in all synapses. The number of vesicles per presynaptic profile also increases with testosterone treatment, primarily due to an increase in the proportion of synapses associated with unusually high vesicle counts. Together, these changes suggest that large reserves of neurotransmitter may be necessary to sustain singing. Several ultrastructural differences between hemispheres are found. Postsynaptic thickenings are longer, and postsynaptic processes are larger on the left side than on the right side. In the spring, there are more vesicles per synapse on the left than on the right, but this lateralization is reversed in the fall. Thus, lateralization of song production is associated with lateral asymmetries in synapse morphology. These hemispheric differences are relatively small, like those seen at the light microscope level, encouraging further consideration of peripheral as well as CNS sources of functional lateralization. The seasonal and testosterone-induced changes in synapse number and morphology may be components of the periodic reorganization of canary vocalization. 相似文献
263.
THE RELATIONSHIP BETWEEN RECRUITING SOURCE, APPLICANT QUALITY, AND HIRE PERFORMANCE: AN ANALYSIS BY SEX, ETHNICITY, AND AGE 总被引:2,自引:0,他引:2
This study investigated both an applicant pool and its resulting class of new hires in an attempt to clarify a number of empirical questions concerning recruiting source effectiveness. A pre-established database of applicants and hires for the job of life insurance agent in a large insurance company was analyzed for recruiting activity. Differences in applicant quality and new hire survival were found in favor of the informal recruiting sources. A second measure of hire success, new business commission credits, failed to show differences across recruiting sources. The informal recruiting sources yielded significantly higher selection ratios than did formal sources for all groups. Examination of recruiting source use showed significant group differences, with females and blacks using the formal recruiting sources more frequently than males, non-minorities, and Hispanics. While the informal recruiting sources yielded higher quality applicants and more successful hires for all groups, this research cautions that the implementation of revised recruiting policies must be carefully monitored for adverse effects on protected groups. 相似文献
264.
This study examined the relations among physical fitness, body image, and locus of control. The Hall-Physical Fitness Test Profile, the Winstead and Cash Body Self-relations Questionnaire (BSRQ) and the Nowicki-Strickland Locus of Control Scale were administered to 243 freshmen. Women were significantly more positive about their physical appearance than men. Men were more positive about their physical fitness than women. Men were more physically fit than women. Men and women scoring in the internal direction viewed the physical fitness domain of their body image positively. Unlike men, internally oriented women had more positive perceptions of the health aspect of their body image. Physically fit men and women had positive attitudes toward the physical fitness component of their body image. Physically fit men differed from physically fit women in that men were more internal and held more positive attitudes toward the physical health dimension of their body images. 相似文献
265.
This study compared normal developing children, aged 34 to 51 mo., on comprehension and production of relative dimensional adjectives using object manipulations in a close elicitation procedure and on Piagetian operational tests of conservation of continuous quantity, length, reversibility and seriation. Analysis indicated a significant difference on the expressive language performance of the transitional and the concrete operational children over the preoperational children, but no significant differences occurred between the first two groups. Children who performed better on seriation were significantly better on expressive language performance. Children classified as operational for length performed better on all language measures than those classified as nonoperational. Reversibility and conservation of a continuous quantity did not differentiate children. 相似文献
266.
267.
T A Aronson 《Psychoanalytic review》1989,76(3):329-351
Many factors go into a choice of a therapeutic focus: the patient's psychopathology; the therapist's training, countertransference reactions, and ideological beliefs; and, importantly, a decision about what seems most amenable to treatment and change. As a theory, self psychology describes one aspect of the paranoid process; as such, it is an incomplete theory that complements rather than invalidates more classical theories. As a technique, however, it suggests a style and focus conducive to working with paranoid patients, one that is markedly supportive, nonconfrontational, yet also interpretive. In this context, it must be remembered how difficult it is to treat paranoid patients psychotherapeutically, much less to keep them in treatment. The strategies discussed above do not wholly replace other dynamic approaches (e.g., counterprojective techniques), nor are they universally applicable. Some patients may be more amenable than others. However, the techniques provide a very supportive framework that may help the therapist to be more available to and in contact with the paranoid patient. More broadly, this paper's application of self psychology to the theory and therapy of the paranoid disorders further illustrates the practical utility of this approach. Attention to the narcissistic developmental line, interpersonal selfobject relationships, intrapsychic conflicts and deficits, and empathic immersion in the patients's world are important adjuncts to the psychotherapy of paranoid patients. Rather than an either/or dichotomy, the principle of overdetermination suggests a both/and relationship between self psychology and traditional theory, such that the self psychological approach complements rather than contradicts the classical psychoanalytic theory. The vicissitudes of the self simply add another perspective or vantage point from which to understand and respond to the patient, one which has perhaps more applicability for preoedipally disordered patients. 相似文献
268.
An organizational field study involving 95 civil service employees examined the ways these individuals coped with the stressful events of their daily living. Lazarus' cognitive-phenomenological analysis of psychological stress provided the theoretical framework. Subjects indicated on Lazarus' Ways of Coping Checklist those coping thoughts and actions used in the specific encounter described as stressful. As hypothesized, individuals experiencing higher diastolic blood pressure were more likely to cope using strategies characterized by wishful thinking, avoidance, and minimization of threat than were individuals exhibiting lower blood pressure. Implications from both an individual and organizational perspective are discussed. 相似文献
269.
Trace mineral analysis of human hair was utilized to determine whether violent and nonviolent criminals could be differentiated on the basis of concentrations of levels of major and trace minerals. 40 violent and 40 nonviolent inmates from a prison population were selected for study. 27 mineral levels were analyzed and a discriminant function analysis correctly classified 86% of the violent and 78% of the nonviolent inmates. The results lent support to the hypothesis that significantly different levels of trace minerals could be found between the two groups. 相似文献
270.
F Postrach 《Psychiatrie, Neurologie, und medizinische Psychologie》1989,41(9):539-544
A case of episodic manifestation of semiparalysis agitans is described, accompanied by severe demential personality change and precursory hallucinatory symptoms, which is made the basis for the discussion of aspects of mental disorders, notably dementia and symptoms resembling schizophrenia, in Parkinsonian patients. By way of allusion to Glass, a diagnosis including a very extensive, complex, symptomatology is made of a Parkinsonian syndrome. 相似文献