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241.
Fos protein expression in olfactory-related brain areas after learning and after reactivation of a slowly acquired olfactory discrimination task in the rat
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Roullet F Liénard F Datiche F Cattarelli M 《Learning & memory (Cold Spring Harbor, N.Y.)》2005,12(3):307-317
Fos protein immunodetection was used to investigate the neuronal activation elicited in some olfactory-related areas after either learning of an olfactory discrimination task or its reactivation 10 d later. Trained rats (T) progressively acquired the association between one odor of a pair and water-reward in a four-arm maze. Two groups of pseudotrained rats were used: PO rats were not water restricted and were submitted to the olfactory stimuli in the maze without any reinforcement, whereas PW rats were water-deprived and systematically received water in the maze without any odorous stimulation. When the discrimination task was well mastered, a significantly lower Fos immunoreactivity was observed in T rats compared to PW and PO rats in most of the analyzed brain areas, which could reflect the post-acquisition consolidation process. Following memory reactivation, differences in Fos immunoreactivity between trained and some pseudotrained rats were found in the anterior part of piriform cortex, CA3, and orbitofrontal cortex. We also observed that Fos labeling was significantly higher in trained rats after memory reactivation than after acquisition of the olfactory task in most of the brain areas examined. Our results support the assumption of a differential involvement of neuronal networks after either learning or reactivation of an olfactory discrimination task. 相似文献
242.
Angiotensin II (ANGII) has an evolutionary preserved role in determining adaptative responses to water-shortages. In addition, it has been shown to modulate diverse phases of memory. Still, it is not clear whether ANGII improves or spoils memory. We demonstrated that endogenous angiotensins enhance consolidation of a long-term associative memory in the crab Chasmagnathus and that water shortage improves memory consolidation through brain ANGII actions. Here, we show that weakly trained crabs, when water-deprived, exhibit enhanced retrieval. Subsequently, memory retention is indistinguishable from that of strongly trained crabs. ANGII, but not angiotensin IV, is a necessary and sufficient condition for such enhancing effect. We conclude that ANGII released due to water shortage leads to enhanced memory retrieval. Thus, it seems that ANGII has an evolutionary preserved role as a multifunction coordinator that enables an adaptative response to water-shortage. The facilitation of memory consolidation and retrieval would be among those coordinated functions. 相似文献
243.
A number of measures have been used in epidemiological studies of children's exposure to community violence, yet the quality
of these instruments is not uniformly good. This paper undertakes a systematic review of the most commonly used (or most promising)
self-report or interview-administered instruments, with regard to their conceptual bases and psychometric properties. Based
on the review, recommendations are made for working with the current state of the science in order to move the field forward.
A key recommendation is for sounder conceptualization of work in the field and greater transparency in the reporting of research,
in order to facilitate the comparability of studies. 相似文献
244.
The aim of this study is to analyze how the length of time a patient spends in an Intensive Care Unit (ICU) affects close relatives, with regard to specific clinical variables of personality, family relationships and fear of death. The study group consisted of 57 relatives of seriously ill patients admitted to the ICU of "Virgen del Rocío" Rehabilitation and Trauma Hospital (Seville, Spain). The instruments applied were: a psychosocial questionnaire, clinical analysis questionnaire, family environment scale and fear of death scale. The relatives of patients admitted to ICU obtained higher scores in hypochondria, suicidal depression, agitation, anxious depression, guilt-resentment, paranoia, psychasthenia, psychological maladjustment and self-expression, and less in fear of their own death, as when compared to interviews with the same relatives 4 years later. The length of time a patient spent in the ICU influenced relatives in some clinical variables of personality, family relationships and fear of death 相似文献
245.
Flores Sarazúa E Borda Más M Pérez San Gregorio MA 《The Spanish journal of psychology》2005,8(1):45-55
The purpose of this survey is to detect common personality features in people infected with AIDS who have a case history of drug addiction and who live in a situation of social exclusion. The sample comprised 105 male participants from the Autonomous Community of Andalusia, divided into 4 groups: (a) 30 men with AIDS, having an intravenous drug addiction case history and who live in a condition of social exclusion; (b) 30 men with IVDA case history, also living in a situation of social exclusion; (c) 15 men in a social exclusion condition; and (d) 30 men in a condition of social adaptation. The evaluation instruments were an author-designed semi-structured interview and the Multiaxial Clinical Inventory (MCMI-II; Millon, 1987). Although some differences were found, the results indicate that there is no specific personality profile in the "social exclusion" population. People in a condition of social exclusion (AIDS, drug addicts, and poor people) may obtain similar scores in the variables studied, but there is no clear specific personality profile in the excluded population, although there may be certain situations in which the segregated groups present similar behaviors. Furthermore, these behaviors do not always correspond to personality features but are adaptive responses to a harsh and complex reality. 相似文献
246.
In the context of a medium-term study designed to integrate the simulation of different types and processes of learning-such as classical, operant, and some cognitive types--one must start with other more elementary ones that are facilitators of the more complex types and processes. Of special interest is habituation, owing to the filtering out of irrelevant stimuli, which means that the simulated agent does not have to respond to them. This paper presents two difference functions constructed to computationally simulate the characteristics that define habituation. The behavior of these functions is described, as are differences arising from stimulus intensity and interstimulus intervals. Results are compared with existing empirical data. 相似文献
247.
Over the last years several European patents were opposed for protecting technology violating the morality requirement under
Article 53(a) EPC. Attempts have been made by the Appeal Boards of the European Patent Office (EPO), as well as by amendments
introduced into the Implementing Regulations of the European Patent Convention (EPC), to address this sensitive patentability
requirement more precisely. The most recent hot topic coming up in this context is the patentability of stem cells. It is
to be expected that this discussion will still go on in the field of biotechnological inventions for the next several years.
An earlier version of this paper was presented at an international conference, “The Ethics of Intellectual Property Rights
and Patents,” held in Warsaw, Poland on 23–24 April, 2004. 相似文献
248.
The odd-even effect is a well documented finding in the literature on mental arithmetic, at least for multiplication. It implies that false answers with the same parity as the correct answer are rejected more slowly than false answers with a different parity. For addition, this effect is not so well documented. The study by Krueger and Hallford (1984) is the only one that investigated odd-even effects for addition. However, they did not investigate odd-even effects per problem, even though there are indications that problem type can modulate odd-even effects for multiplication (Lemaire & Reder, 1999). Therefore, we wanted to get more insight into odd-even effects for addition by investigating odd-even effects per problem type. Our results extended the findings of Krueger and Hallford. First of all, we found an interaction between split and problem type. The most important and new result of present study, however, was a strong parity effect for E + E problems. We discuss our results in terms of two alternative explanations for odd-even effects, namely use of a parity rule on the one hand and familiarity with even outcomes on the other. 相似文献
249.
A number of studies have shown that the scale of social dominance orientation (SDO), used to measure the degree of preference
for inequality among social groups, is a predictive measure of social and political attitudes toward stigmatized outgroups.
However, the relationship between SDO and discrimination has received little attention. The main goal of this study was to
assess the validity of a new computer-based method used to measure discriminatory behaviors in a laboratory setting. An additional
goal was to test the mediating role of prejudice in the relation between SDO and discrimination. The results provide a first
validation of this new method and demonstrate that the effect of SDO on discrimination is mediated by prejudice. 相似文献
250.
Dorothée?LegrandEmail author Franck?Grammont 《Phenomenology and the Cognitive Sciences》2005,4(3):249-257
We discuss the justification of Bickle's “ruthless” reductionism. Bickle intends to show that we know enough about neurons
to draw conclusions about the “whole” brain and about the mind. However, his reductionism does not take into account the complexity
of the nervous system and the fact that new properties emerge at each significant level of integration from the coupled functioning
of elementary components. From a methodological point of view, we argue that neuronal and cognitive models have to exert a
mutual constraint(MC) on each other. This approach would refuse to award any priority of cognitive approaches over neuroscience, and reciprocally,
to refuse any priority of neuroscience over cognitive approaches. MC thus argues against radicalreductionism at the methodological level. 相似文献