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991.
Van der Jeugd A Ahmed T Burnouf S Belarbi K Hamdame M Grosjean ME Humez S Balschun D Blum D Buée L D'Hooge R 《Neurobiology of learning and memory》2011,95(3):296-304
We evaluated various forms of hippocampus-dependent learning and memory, and hippocampal synaptic plasticity in THY-Tau22 transgenic mice, a murine tauopathy model that expresses double-mutated 4-repeat human tau, and shows neuropathological tau hyperphosphorylation and aggregation throughout the brain. Focussing on hippocampus, immunohistochemical studies in aged THY-Tau22 mice revealed prominent hyper- and abnormal phosphorylation of tau in CA1 region, and an increase in glial fibrillary acidic protein (GFAP) in hippocampus, but without signs of neuronal loss. These mice displayed spatial, social, and contextual learning and memory defects that could not be reduced to subtle neuromotor disability. The behavioral defects coincided with changes in hippocampal synaptic functioning and plasticity as measured in paired-pulse and novel long-term depression protocols. These results indicate that hippocampal tauopathy without neuronal cell loss can impair neural and behavioral plasticity, and further show that transgenic mice, such as the THY-Tau22 strain, might be useful for preclinical research on tauopathy pathogenesis and possible treatment. 相似文献
992.
In two experiments we tested the hypothesis that cognitive processing based on spatial imagery produces more deterioration of visual perception than cognitive processing based on verbal codes. So, we studied the effect on visual perception of two cognitive tasks, one of spatial imagery and the other a verbal task. In the first one, with 30 participants, we analyzed the mental load and ocular behaviors in both cognitive tasks. In the second experiment, with 29 participants, we studied the effect of both tasks on a visual search task, using a dual-task experimental paradigm. The verbal task presented higher mental load than the imagery task when both tasks were carried out with visual search task, and there was more deterioration in stimulus detection with the verbal task. We can conclude that: (1) cognitive tasks produce important deterioration in the capacities of visual search and identification of stimuli; (2) this deterioration has two components: (a) an inefficient search, associated with alterations of the gaze patterns while performing cognitive tasks, and (b) a general interference, nonspecific to spatial codes, in the process of identification of looked-at stimuli; (3) this cognitive interference is related to the mental load or effort required by the cognitive task. 相似文献
993.
We review and discuss A. H. Louie’s book “More than Life Itself: A Reflexion on Formal Systems and Biology” from an interdisciplinary
viewpoint, involving both biology and mathematics, taking into account new developments and related theories. 相似文献
994.
Piqueras JA Olivares J Hidalgo MD Vera-Villarroel P Marzo JC 《The Spanish journal of psychology》2011,14(2):977-989
The aim of this work was to update the validation of the Social Anxiety Screening Scale (SASS/EDAS) in a sample of Spanish adolescents. To achieve this, one study with a sample of 1489 students in secondary education, of ages 14 to 17 years, were carried out. The psychometric properties of EDAS were examined through confirmatory factor analysis, reliability (Cronbach's alpha), temporal stability (test-retest), and concurrent criterion validity. The results supported the three-independent-factor structure (avoidance, distress and interference), that showed best fit indices compared to alternative models. They also showed that the scores of participants on EDAS scales were reliable in terms of internal consistency (alpha > .80) and moderately reliable concerning temporal stability (r = .48-.60) over a five-week period. The correlations between the EDAS factors and other social anxiety measures were positive and significant. Data provide empirical evidence of the estimation of reliability and validity of this scale. Future work should extend the validation of the EDAS in clinical samples. 相似文献
995.
Noëmi Manders-Huits 《Science and engineering ethics》2011,17(2):271-287
Recently, there is increased attention to the integration of moral values into the conception, design, and development of
emerging IT. The most reviewed approach for this purpose in ethics and technology so far is Value-Sensitive Design (VSD).
This article considers VSD as the prime candidate for implementing normative considerations into design. Its methodology is
considered from a conceptual, analytical, normative perspective. The focus here is on the suitability of VSD for integrating
moral values into the design of technologies in a way that joins in with an analytical perspective on ethics of technology.
Despite its promising character, it turns out that VSD falls short in several respects: (1) VSD does not have a clear methodology
for identifying stakeholders, (2) the integration of empirical methods with conceptual research within the methodology of
VSD is obscure, (3) VSD runs the risk of committing the naturalistic fallacy when using empirical knowledge for implementing
values in design, (4) the concept of values, as well as their realization, is left undetermined and (5) VSD lacks a complimentary
or explicit ethical theory for dealing with value trade-offs. For the normative evaluation of a technology, I claim that an
explicit and justified ethical starting point or principle is required. Moreover, explicit attention should be given to the
value aims and assumptions of a particular design. The criteria of adequacy for such an approach or methodology follow from
the evaluation of VSD as the prime candidate for implementing moral values in design. 相似文献
996.
Oliver Dickhäuser Marc-André Reinhard Chris Englert 《Social Psychology of Education》2011,14(4):519-528
The importance of performance expectancies for the prediction of regulation of behavior and actual performance has long been
established. Building on theories from the field of social cognition, we suggest that the level of performance expectancies,
as well as the certainty of the expectancy, have a joint influence on an individual’s beliefs and behavior. In two studies
(one cross sectional using a sample of secondary school students and one longitudinal using a sample of university students)
we found that expectancies more strongly predicted persistence, and subsequent performance, the more certain the expectancy
was. This pattern was found even if prior performance was controlled, as in Study 2. The data give an indication that it may
be useful to include certainty as an additional variable in expectancy models. 相似文献
997.
This two-wave longitudinal study examines the ability of life satisfaction and adjustment strategies to predict anxious and
depressive symptoms in coronary heart disease male patients. Studies have shown that most heart attack survivors report these
symptoms, which may worsen the prognosis of the disease. At Time 1, immediately after the first cardiac episode, eighty-eight
men reported their life satisfaction levels, adjustment strategies used, and anxious and depressive symptoms experienced.
At Time 2, six months later, sixty-three of those patients reported only their anxious and depressive symptoms again. The
results showed that, after controlling for demographic variables, anxious and depressive symptoms at Time 1 were predicted
by positive adjustment and life satisfaction. At Time 2, after controlling for both demographic variables and Time 1-emotional
symptoms, none of the psychological variables predicted anxious symptoms, while depressive symptoms were only predicted by
life satisfaction. It is concluded that an adequate level of life satisfaction may help to decrease emotional distress, both
short and long term, while the use of positive adjustment strategies is especially important immediately after diagnosis. 相似文献
998.
Magdalena Bobowik Nekane Basabe Darío Páez Amaia Jiménez M. Ángeles Bilbao 《Journal of Happiness Studies》2011,12(3):401-419
The aim of this study was to analyze the relationship between personal values and well-being. Two correlational studies are
presented with the following random samples: (1) four native samples: two samples from the 2006 European Social Survey (Europe
n1 = 28,375, Spain n2 = 1,321) and two Basque samples (n3 = 1,770; n4 = 820); and (2) a sample of immigrants in the Basque Country (quasirandom) (n5 = 1,171). Age range of respondents was 18–60 years. The instruments used were for measuring: (1) personal values (Schwartz’s
PVQ-40 or PVQ-21), and (2) well-being (Bradburn’s PNA, Goldberg’s GHQ, and life satisfaction and perceived control items from
the World Value Survey). Partial correlation analysis was applied, with PVQ scale response bias controlled. The data supported
a positive association of hedonic and psychological well-being with openness to experience and individualist values, and a
negative association with power and conservation or collectivist values. Satisfaction with life partially mediated the relationship
between personal values and affect. The results support a universal association of healthy values with well-being. 相似文献
999.
Owing to the sexuation of occupations associating technical attributes with men and relational skills with women, the latter are less numerous in professions where driving is involved. The negative stereotype associating women with poor driving skills is thus likely to have a cognitive and behavioral impact. According to the model of the stereotype threat, could activation of the threat inhibit the performance of women in a Highway Code test? After performing an association task that demonstrated a largely negative stereotype, 56 female students took a Highway Code test in two conditions: an experimental condition where the stereotype was activated by a comparison between men and women (N = 17); and a control condition without activation (N = 39). Subjects performed less well in the experimental condition, demonstrating the expected effects of the stereotype threat. 相似文献
1000.
There is accumulating evidence that a variety of species possess quantitative abilities although their cognitive substrate
is still unclear. This study is the first to investigate whether sea lions (Otaria flavescens), in the absence of training, are able to assess and select the larger of two sets of quantities. In Experiment 1, the two
sets of quantities were presented simultaneously as whole sets, that is, the subjects could compare them directly. In Experiment
2, the two sets of quantities were presented item-by-item, and the totality of items was never visually available at the time
of choice. For each type of presentation, we analysed the effect of the ratio between quantities, the difference between quantities
and the total number of items presented. The results showed that (1) sea lions can make relative quantity judgments successfully
and (2) there is a predominant influence of the ratio between quantities on the subjects’ performance. The latter supports
the idea that an analogue representational mechanism is responsible for sea lions’ relative quantities judgments. These findings
are consistent with previous reports of relative quantities judgments in other species such as monkeys and apes and suggest
that sea lions might share a similar mechanism to compare and represent quantities. 相似文献