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31.
Electrical activity was recorded from single neurons in the medial prefrontal cortex of rabbits during differential Pavlovian heart rate (HR) conditioning. A heterogeneous population of cells were found, some of which showed CS-evoked increases and others CS-evoked decreases in discharge, while some cells were biphasic. A subset of cells also showed trial-related changes in discharge that were related to acquisition of the HR discrimination between the reinforced CS+ and non-reinforced CS-. Administration of the peripheral cholinergic antagonist, methylscopolamine, and the andrenergic antagonist, atenolol, either increased or decreased maintained baseline activity of many cells, but had little or no effect on the CS-evoked activity of these cells. Waveform changes also did not result from administration of these drugs. This finding suggests that CS-evoked mPFC activity is not being driven by cardiac afferent input to CNS cardiac control centers. Previous studies have shown that ibotenic acid lesions of this area greatly decreases the magnitude of decelerative heart rate conditioned responses; the latter finding, plus the results of the present study, suggest that processing of CS/US contingencies by the prefrontal cortex contributes to the acquisition of autonomic changes during Pavlovian conditioning.  相似文献   
32.
Using an adaptation of the Attentional Networks Test, we investigated aspects of executive control in children with chromosome 22q11.2 deletion syndrome (DS22q11.2), a common but not well understood disorder that produces non-verbal cognitive deficits and a marked incidence of psychopathology. The data revealed that children with DS22q11.2 demonstrated greater difficulty than controls in locating and processing target items in the presence of distracters. Importantly, children with DS22q11.2 showed a deficit in the ability to monitor and adapt to stimulus conflict. These data provide evidence of inadequate conflict adaptation in children with DS22q11.2, a problem that is also present in schizophrenia. The findings of specific executive dysfunction in this group may provide a linkage between particular genetic abnormalities and the development of psychopathology.  相似文献   
33.
A growing number of studies have supported the use of unidimensional psychometric test instruments administered via the Internet; however, support for the use of multidimensional scales is weak. The present study compares paper and Internet administrations of the Multidimensional Health Locus of Control (MHLC) Scale (Wallston & Wallston, 1981). In terms of reliabilities and factor structures, the Internet data were found to be at least as good as the paper data. MHLC scores were comparable for paper and Internet administrations, although the Internet sample scored significantly lower on the Powerful Others subscale. Overall, the results show that administration of the MHLC Scale via the Internet can produce data comparable to that obtained by pen-and-paper methods. However, it is concluded that generalization of these findings beyond the psychometric test instrument and sampling procedures used here is not warranted.  相似文献   
34.
Two experiments investigated the effect of visual blank space on reading by varying the amount of interletter and interline blank space in prose passages. Increasing interletter blank spacing slowed the reading process overall, presumably because it disrupted the unitization of words and word identification, but it also improved the identification of the letters within words. By contrast, increasing interline blank spacing sped up the reading process overall, while also improving the identification of words and the letters within words, presumably because the extra spacing reduced the amount of visual information that was processed during reading. The latter finding supports the conclusion that information from surrounding lines of single-spaced text may interfere with reading.  相似文献   
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36.
During the nearly 10 years since its introduction, preimplantation genetic diagnosis (PGD) has been used predominantly to avoid giving birth to a child with identified genetic disease. Recently, PGD was used by a couple not only to test IVF-created embryos for genetic disease, but also to test for a nondisease trait related to immune compatibility with a child in the family in need of an hematropoetic stem cell transplant. This article describes the case, raises some ethical and policy issues, highlights gaps in U.S. policy, and finally makes some recommendations for addressing advancing genetic and reproductive technologies.  相似文献   
37.
Extinction of escape behavior in the water maze due to the removal of the platform, was hypothesized to induce a negative state, including the development of immobility, which is held to reflect a state of "despair" when measured in the forced swimming test. 27 aged and 8 adult animals (26 and 3 months old Wistar rats, respectively) were tested in the water maze during nine days with a platform hidden, followed by 7 days of extinction trials with the platform absent. As expected, both age groups developed immobility over the extinction trials, with the aged showing more than the adults. To examine whether the age difference in immobility was related to performance differences during acquisition, the aged were subdivided into superior, intermediate and inferior learners (n = 9 per group) on the basis of overall times to platform during acquisition, and compared with each other and the adults. Results showed that the aged inferior learners displayed the highest levels of immobility among the aged. Immobility scores were then correlated with post-mortem neurotransmitter contents in the hippocampus and ventral striatum. In the ventral striatum, levels of immobility were correlated with levels of acetylcholine, dopamine and the metabolite dihydroxyphenylacetic acid in the aged, and with norepinephrine in the adults. The data support the hypothesis that multiple extinction trials in the water maze result in immobility that may indicate "behavioral despair," and that striatal neurotransmitter systems correlate with the degree of its expression. The concept of extinction-induced despair is held to provide the promise of a conceptual and empirical model of human depression that is the consequence of loss of reinforcers.  相似文献   
38.
Psychoanalytic psychotherapy in clinical practice is traditionally a long-term treatment conducted by well-trained psychotherapists. However, very few studies have been published that evaluate the effects of such treatment. To redress this lack of studies, 55 individuals selected for long-term psychoanalytic psychotherapy (average, 3 years) were invited to participate in a naturalistic study. The psychotherapists had a mean of 15 years of professional experience. The 36 patients who completed psychotherapy manifested a substantial reduction in symptomatic suffering and decreased levels of character pathology, as measured by the Karolinska Psychodynamic Profile (KAPP) and the Karolinska Scales of Personality. Generally, such changes were not found in the individuals who did not engage in treatment. In the therapy group, improvements were found on eight KAPP subscales defining different aspects of character: Intimacy and Reciprocity, Frustration Tolerance, Regression in the Service of the Ego, Coping with Aggressive Affects, Conceptions of Bodily Appearance and their Significance for Self-esteem, Sexual Function, Sexual Satisfaction, and Personality Organization. The results indicate that individuals who engaged in psychotherapy improved their capacity to handle crucial aspects of life and reduced their symptomatic suffering.  相似文献   
39.
In this study, the authors examined the effects of social comparison on the life satisfaction of 455 community-dwelling older persons. These older persons were confronted with a fictitious interview with either an upward or a downward target. After downward comparison, older persons felt more satisfied with their lives than after upward comparison, especially those who had higher levels of frailty. These effects were only found with lower levels of identification. Apparently, downward comparison only serves its self-enhancing function on life satisfaction among frail older persons when they perceive the comparison target as different from themselves.  相似文献   
40.
The managers of beach businesses were randomly assigned to receive no intervention or two newsletters per week for 6 weeks that presented economic consequences of damage to coastal water quality and how to contact politicians. The percentage of proenvironmental political contacts was significantly greater in the experimental (newsletter) group than in the control group. Logistical regression showed that contacts in the newsletter group were more than five times that of controls after adjusting for history of contacts and predisposition to take such action. Results suggest that the intervention can promote political action that could influence environmental policies and human health.  相似文献   
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