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231.
Norway rat fetuses (Rattus norvegicus) exhibit a stereotypic behavioral response when the umbilical cord is experimentally compressed with a vascular clamp. In this study, the development of the fetal behavioral response to cord compression was compared in altricial and precocial rodents, which differ markedly in neural and motor maturity at the time of birth. Both altricial and precocial species showed some form of behavioral response to umbilical cord compression. Fetuses of two altricial species, Norway rats and Mongolian gerbils (Meriones unguiculatus), expressed hyperactivity in response to cord compression throughout the last third of gestation. In contrast, precocial cotton rats (Sigmodon hispidus) and spiny mice (Acomys cahirinus) did not respond to cord compression until relatively late in gestation. Thus, altricial and precocial species do not express the cord compression response during comparable periods of neural development: precocial species are much more mature at the earliest expression of this behavior than altricial species. These findings are consistent with the interpretation that the cord compression response is a behavioral adaptation that can promote survival of the fetus in utero. 相似文献
232.
Reports that the dihydropyridine Ca2+ channel antagonists may facilitate memory led to the present study of the behavioral effects of nifedipine. Ninety-two 4-day-old male chicks received 0, 100 nM, 100 microM, or 10 mM nifedipine. Drugs were administered in volumes of 2 microliters into the fourth cerebral ventricle 5 min before training on a visual discrimination task. Nifedipine did not produce any detectable changes in behavior during acquisition trials. Retention, however, was impaired 24 h after training in the 100 nM and 100 microM nifedipine-treated chicks, which made significantly more errors than controls. Nifedipine did not affect the amount of time required to complete the task. No effects on body weight gain were detected, suggesting that the memory impairment was not due to a change in feeding behavior. These data are discussed in terms of the role of calcium-dependent processes in memory. 相似文献
233.
A multivariate hierarchical model of specific cognitive abilities was fitted to data from 7-year-old adopted and nonadopted sibling pairs in the Colorado Adoption Project in order to assess differential genetic influence on specific mental abilities. Model fitting results and Schmid-Leiman (Schmid & Leiman, 1957) transformations reveal significant heritable variation for verbal, spatial, and memory factors independent of general cognitive ability for the eight ability tests examined. In contrast, environmental influences are primarily measure-specific. The results suggest genetic effects in middle childhood that differentially influence mental ability scores. 相似文献
234.
Patterns of coping with cancer. 总被引:12,自引:0,他引:12
We identified five patterns of coping in a sample of 603 cancer patients: "seeking or using social support," "focusing on the positive," "distancing," "cognitive escape-avoidance," and "behavioral escape-avoidance." Relationships of these coping patterns to sociodemographic characteristics, medical factors, stress appraisals, psychotherapeutic experience, and emotional distress were tested using correlational and regression techniques. Type of cancer, time since diagnosis, and whether a person was currently in treatment had few or no relationships to coping. The specific cancer-related problem (e.g., pain, fear of future) was also not associated with how individuals coped. Perceptions of its stressfulness, however, were related to significantly more coping through social support and more of both forms of escape-avoidance. Coping through social support, focusing on the positive, and distancing was associated with less emotional distress, whereas using cognitive and behavioral escape-avoidance was associated with more emotional distress. Implications of the results for understanding coping processes and intervention with cancer patients are discussed. 相似文献
235.
H Intraub R S Bender J A Mangels 《Journal of experimental psychology. Learning, memory, and cognition》1992,18(1):180-191
Ss tend to remember close-up photographs as having had extended boundaries (Intraub & Richardson, 1989). Three alternate explanations were tested: object completion, distortion toward a perceptual schema, and normalization toward a prototypic view. In three experiments, 55-130 undergraduates viewed 16 close-up, prototypic, or wide-angle views of objects for 15 s each. Immediately or 48 hr later, they rated test pictures on a 5-point scale as "same", "closer up", or "father away." Results ruled out object completion because boundary extension occurred when the picture contained no incomplete objects. Immediate tests supported the perceptual schema hypothesis because all unidirectional distortions involved boundary extension. Delayed tests were more suggestive of a memory schema effect because wide-angle pictures yielded boundary restriction. A two-component model of picture processing is proposed. 相似文献
236.
Anterior cerebral asymmetry and the nature of emotion. 总被引:14,自引:0,他引:14
R J Davidson 《Brain and cognition》1992,20(1):125-151
This article presents an overview of the author's recent electrophysiological studies of anterior cerebral asymmetries related to emotion and affective style. A theoretical account is provided of the role of the two hemispheres in emotional processing. This account assigns a major role in approach- and withdrawal-related behavior to the left and right frontal and anterior temporal regions of two hemispheres, respectively. Individual differences in approach- and withdrawal-related emotional reactivity and temperament are associated with stable differences in baseline measures of activation asymmetry in these anterior regions. Phasic state changes in emotion result in shifts in anterior activation asymmetry which are superimposed upon these stable baseline differences. Future directions for research in this area are discussed. 相似文献
237.
238.
Fernand R. Gobet 《Psychological research》1992,54(1):38-43
Summary The effects of noncontingency between subjects' responses and outcomes were examined with respect to treatment-and-posttest similarity and skill in the task. The experimental design consisted of three groups. The first group had to solve chess problems with objective solutions and received veridical feedback; each member of the second group faced problems with no objective solutions, and received the same feedback as the member of the first group he was yoked with, but without any control on it; the control group received a waiting task. It was found at the end of the experiment that the group with unsolvable problems was more depressed than the two other groups. The mid-strength players were the most sensitive to the manipulation, and the weakest players showed little effect of learned helplessness. It was also found that the effects were proportional to the degree of similarity between the treatment and the posttest. The results limit the domain of applicability of the learned-helplessness model. 相似文献
239.
Mark R. Wiederanders 《Behavioral sciences & the law》1992,10(1):141-148
Postinstitutional arrests and state hospitalizations of 191 patients placed on conditional release (CONREP group) were compared to those of 44 patients released from the same California state hospital with no aftercare due to expiration of commitment terms (MAXOUT group). The two groups were not randomly determined but were comparable in demographic characteristics and rates of preprogram arrest. The CONREP group had a significantly lower community-period arrest rate than did the MAXOUT group (p <.001). Survival rate analyses, using time until arrest and time until revocation as dependent variables, suggested that revocations during the first 240 days of community re-entry reduced the potential arrest rate within the CONREP group. Results were discussed in terms of the “criminalization hypothesis” as well as the crime-preventive possibilities of the conditional release mechanism. 相似文献
240.
Eighty younger (less than 50 years, M = 28 years) and 80 older (more than 50 years, M = 69 years) Type A and Type B Ss were evaluated for Type A behavior pattern using the Structured Interview (SI) and given personality tests for anxiety, depression, anger, aggression, hostility, and anger-in-anger-out. Ss also underwent an emotion induction procedure. Videotapes of the emotion induction procedure (N = 160) and the SI (N = 80) were coded for facial expression of emotion. Type As did not differ from Bs on anxiety or depression but did on anger and aggression. Type As showed anger inhibition and anger bound to shame, as predicted by emotion socialization theory. The greatest number of differential effects were observed between age groups. Older individuals, in general, were more emotionally expressive than younger Ss across a range of emotions. Women appeared more conflicted about anger expression than men, and Type A women more so than Type A men. 相似文献