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991.
In this paper, we used the data of Mathematics achievements from the sample of 13- year-old Spanish boys and girl who took part in the Second National Assessment of Educational Progress, carried out by the Educational Testing Service. With the aim of identifying variables related to high achievement, our goals are: 1) to analyse whether there are significant differences in 13-year-old Spanish boys and girls in their attitudes towards mathematics, their study strategies, and their performance; 2) to analyse the influence of their attitudes and study strategies on their performance, and to examine whether these relations are the same in boys and girls; 3) to propose a theoretical model that explains the relationship among the variables defined by means of structural equation modelling. The results show that: a) there are significant differences between boys and girls in the variables studied; b) it is not possible to reject the proposed model that relates study strategies and attitudes towards performance in mathematics; and c) the model tends to be stable both among boys and girls.  相似文献   
992.
The aim of this research was to analyse the psychological profile of potential organ donors and potential non-organ donors, from a sample of people with qualifications lower than a Bachelor's degree. The variables examined were prosocial behaviour, the scales of the Constructive Thinking Inventory, and the dimensions of personality of the Big-Five Questionnaire. The results show that non-organ donors have a lower score in prosocial behaviour, are less efficient in their actions, with a tendency for less thought before acting, and they tend to be prejudiced. The results also reveal that this group has lower degrees of cooperation and empathy. They tend to be less reflective, less scrupulous, less willing to persevere in their actions, less interested in culture, and less open to new ideas and values. The above results are discussed, bearing in mind the utility of this knowledge to professionals dedicated to organ donation.  相似文献   
993.
We examine the inflectional productions of seven Catalan, seven Galician, and seven Spanish speaking agrammatic subjects in an elicitation and a sentence repetition task and consider them in the light of the Tree Pruning Hypothesis (TPH). The results show relatively spared subject person/number agreement with the verb and impaired tense marking for all subjects in all the languages. Recent reformulations of syntactic theory [Chomsky (1999) MIT Occasional Papers in Linguistics (vol. 18). MA: The MIT Press; (2000). Step by Step: Essays on Minimalist Syntax in Honor of Howard Lasnik (pp. 89–155). Cambridge, MA: The MIT Press] regarding the locus of agreement force a reconsideration of the TPH for it to make the desired predictions; we adopt Cinque’s [(1999) Adverbs and Functional Heads: A Cross-linguistic Perspective. Oxford: Oxford University Press] array of functional mood/tense/aspect projections and we show that subject agreement must occur between the subject DP and a low functional head for selective impairment to result. Feature underspecification, formerly considered, is rendered unnecessary.  相似文献   
994.
The authors argue that human sequential learning is often but not always characterized by a shift from stimulus- to plan-based action control. To diagnose this shift, they manipulated the frequency of 1st-order transitions in a repeated manual left-right sequence, assuming that performance is sensitive to frequency-induced biases under stimulus- but not plan-based control. Indeed, frequency biases tended to disappear with practice, but only for explicit learners. This tendency was facilitated by visual-verbal target stimuli, response-contingent sounds, and intentional instructions and hampered by auditory (but not visual) noise. Findings are interpreted within an event-coding model of action control, which holds that plans for sequences of discrete actions are coded phonetically, integrating order and relative timing. The model distinguishes between plan acquisition, linked to explicit knowledge, and plan execution, linked to the action control mode.  相似文献   
995.
Masked stimuli (primes) can affect the preparation of a motor response to subsequently presented target stimuli. Under some conditions, reactions to the main stimulus can be facilitated (straight priming) or inhibited (inverse priming) when preceded by a compatible prime (calling for the same response). In the majority of studies in which inverse priming was demonstrated arrows pointing left or right were used as prime and targets. There is, however, evidence that arrows are special overlearned stimuli which are processed in a favorable way. Here we report three experiments designated to test whether the "arrowness" of primes/targets is a sufficient condition for inverse priming. The results clearly show that although inverse priming appeared when non-arrow shapes were used, the magnitude of the priming effect was larger with arrows. The possible reasons for this effect are discussed.  相似文献   
996.
Three hundred and nine nonpatient adults, evenly distributed according to sex, age, educational level, and residence, took part in the Rorschach test study carried out in Portugal. The sample was drawn from selected regions of the country and was balanced for population density in urban and rural areas. Test administration was controlled through the services of psychologists familiar with the Rorschach Comprehensive System (CS; Exner, 1993). Results indicate that, in Portugal (Pires, 2000), level of education is the variable that seems to have the largest effect on Rorschach responding.  相似文献   
997.
The conditions under which symmetry and equivalence relations develop are still controversial. This paper reports three experiments that attempt to analyze the impact of multiple-exemplar training (MET) in receptive symmetry on the emergence of visual-visual equivalence relations with a very young child, Gloria. At the age of 15 months 24 days (15m24d), Gloria was tested for receptive symmetry and naming and showed no evidence of either repertoire. In the first experiment, MET in immediate and delayed receptive symmetrical responding or listener behavior (from object-sound to immediate and delayed sound-object selection) proceeded for one month with 10 different objects. This was followed, at 16m25d, by a second test conducted with six new objects. Gloria showed generalized receptive symmetry with a 3-hr delay; however no evidence of naming with new objects was found. Experiment 2 began at 17m with the aim of establishing derived visual-visual equivalence relations using a matching-to-sample format with two comparisons. Visual-visual equivalence responding emerged at 19m, although Gloria still had not shown evidence of naming. Experiment 3 (22m to 23m25d) used a three-comparison matching-to-sample procedure to establish visual-visual equivalence. Equivalence responding emerged as in Experiment 2, and naming emerged by the end of Experiment 3. Results are discussed in terms of the history of training in bidirectional relations responsible for the emergence of visual-visual equivalence relations and of their implications for current theories of stimulus equivalence.  相似文献   
998.
Presence of depression in cocaine-dependent users is relevant for treatment of these persons. This study assessed the presence of depressive symptomatology with a published Spanish translation of the Beck Depression Inventory for a sample of 115 Spanish cocaine-dependent users who were in outpatient treatment at Centers of Drug Dependence of Galicia, Spain. The mean score was 13.7 (SD = 10.3), with 24.3% of the sample having scores which indicate clinical depression (cut off > or =21). These data underscore the need to assess the presence of depression in cocaine-dependent users who require treatment.  相似文献   
999.
Adenosine receptors in the central nervous system have been implicated in the modulation of different behavioural patterns and cognitive functions although the specific role of A(2A) receptor (A(2A)R) subtype in learning and memory is still unclear. In the present work we establish a novel transgenic rat strain, TGR(NSEhA2A), overexpressing adenosine A(2A)Rs mainly in the cerebral cortex, the hippocampal formation, and the cerebellum. Thereafter, we explore the relevance of this A(2A)Rs overexpression for learning and memory function. Animals were behaviourally assessed in several learning and memory tasks (6-arms radial tunnel maze, T-maze, object recognition, and several Morris water maze paradigms) and other tests for spontaneous motor activity (open field, hexagonal tunnel maze) and anxiety (plus maze) as modification of these behaviours may interfere with the assessment of cognitive function. Neither motor performance and emotional/anxious-like behaviours were altered by overexpression of A(2A)Rs. TGR(NSEhA2A) showed normal hippocampal-dependent learning of spatial reference memory. However, they presented working memory deficits as detected by performance of constant errors in the blind arms of the 6 arm radial tunnel maze, reduced recognition of a novel object and a lack of learning improvement over four trials on the same day which was not observed over consecutive days in a repeated acquisition paradigm in the Morris water maze. Given the interdependence between adenosinic and dopaminergic function, the present results render the novel TGR(NSEhA2A) as a putative animal model for the working memory deficits and cognitive disruptions related to overstimulation of cortical A(2A)Rs or to dopaminergic prefrontal dysfunction as seen in schizophrenic or Parkinson's disease patients.  相似文献   
1000.
Transient long-term potentiation (E-LTP) can be transformed into a long-lasting LTP (L-LTP) in the dentate gyrus (DG) by behavioral stimuli with high motivational content. Previous research from our group has identified several brain structures, such as the basolateral amygdala (BLA), the locus coeruleus (LC), the medial septum (MS) and transmitters as noradrenaline (NA) and acetylcholine (ACh) that are involved in these processes. Here we have investigated the functional interplay among brain structures and systems which result in the conversion of a E-LTP into a L-LTP (reinforcement) by stimulation of the BLA (BLA-R). We used topical application of specific drugs into DG, and other targets, while following the time course of LTP induced by stimulation of the perforant pathway (PP) to study their specific contribution to BLA-R. One injection cannula, a recording electrode in the DG and stimulating electrodes in the PP and the BLA were stereotactically implanted one week before electrophysiological experiments. Topical application of atropine or propranolol into the DG blocked BLA-R in both cases, but the effect of propranolol occurred earlier, suggesting a role of NA within the DG during an intermediate stage of LTP maintenance. The injection of lidocaine into the LC abolished BLA-R indicating that the LC is part of the functional neural reinforcing system. The effect on the LC is mediated by cholinergic afferents because application of atropine into the LC produced the same effect. Injection of lidocaine inactivating the MS also abolished BLA-R. This effect was mediated by noradrenergic afferents (probably from the LC) because the application of propranolol into the MS prevented BLA-R. These findings suggest a functional loop for BLA-R involving cholinergic afferents to the LC, a noradrenergic projection from the LC to the DG and the MS, and finally, the cholinergic projection from the MS to the DG.  相似文献   
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