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941.
Del Villar F García González L Iglesias D Perla Moreno M Cervelló EM 《Perceptual and motor skills》2007,104(2):355-365
This study deals with decision and execution behavior of tennis players during competition. The study is based on the expert-novice paradigm and aims to identify differences between both groups in the decision-making and execution variables in serve and shot actions in tennis. Six expert players (elite Spanish tennis players) and six novice players (grade school tennis players) took part in this study. To carry out this study, the observation protocol defined by McPherson and Thomas in 1989, in which control, decision-making and execution variables were included, was used, where it was applied to the performance of the tennis player in a real match situation. In the analysis, significant differences between experts and novices in decision-making and execution variables are found wherein it can be observed that experts display a greater ability to make the appropriate decisions, selecting the most tactical responses to put pressure on the opponent. Expert tennis players were also able to carry out forceful executions to their opponent with greater efficiency, making the opponent's response to a large extent more difficult. These findings are in accordance with those of McPherson and colleagues. 相似文献
942.
Palmero EI Ashton-Prolla P da Rocha JC Vargas FR Kalakun L Blom MB Azevedo SJ Caleffi M Giugliani R Schüler-Faccini L 《Journal of genetic counseling》2007,16(3):363-371
Hereditary breast cancer (HBC) accounts for 5–10% of breast cancer cases and it significantly increases the lifetime risk
of cancer. Our objective was to evaluate the sociodemographic variables, family history of cancer, breast cancer (BC) screening
practices and the risk profile of cancer affected or asymptomatic at-risk women that undergo genetic counseling for hereditary
breast cancer in public Brazilian cancer genetics services. Estimated lifetime risk of BC was calculated for asymptomatic
women using the Gail and Claus models. The majority of women showed a moderate lifetime risk of developing BC, with an average
risk of 19.7% and 19.9% by the Gail and Claus models, respectively. The average prior probability of carrying a BRCA1/2 gene mutation was 16.7% and overall only 32% fulfilled criteria for a hereditary breast cancer syndrome as assessed by family
history. We conclude that a significant number of individuals at high-risk for HBC syndromes may not have access to the benefits
of cancer genetic counseling in these centers. Contributing factors may include insufficient training of healthcare professionals,
disinformation of cancer patients; difficult access to genetic testing and/or resistance in seeking such services. The identification
and understanding of these barriers is essential to develop specific strategies to effectively achieve cancer risk reduction
in this and other countries were clinical cancer genetics is not yet fully established. 相似文献
943.
Causal judgment is assumed to play a central role in prediction, control, and explanation. Here, we consider the function
or functions that map contingency information concerning the relationship between a single cue and a single outcome onto causal
judgments. We evaluate normative accounts of causal induction and report the findings of an extensive meta-analysis in which
we used a cross-validation model-fitting method and carried out a qualitative analysis of experimental trends in order to
compare a number of alternative models. The best model to emerge from this competition is one in which judgments are based
on the difference between the amount of confirming and disconfirming evidence. A rational justification for the use of this
model is proposed. 相似文献
944.
Bekinschtein P Katche C Slipczuk LN Igaz LM Cammarota M Izquierdo I Medina JH 《Neurobiology of learning and memory》2007,87(2):303-307
It is widely accepted that the formation of long-term memory (LTM) requires mRNA translation, but little is known about the cellular mechanisms in the brain that regulate this process. Mammalian target of rapamycin (mTOR) is a key regulator of translational efficacy and capacity. Here, we show that LTM formation of one-trial inhibitory avoidance (IA) in rats, a hippocampus-dependent fear-motivated learning task, requires mTOR activation. IA training is specifically associated with a rapid increase in the phosphorylation state of mTOR and its substrate ribosomal S6 kinase (p70S6K). Bilateral intra-CA1 infusion of rapamycin, a selective mTOR inhibitor, 15 min before, but not immediately after training completely hinders IA LTM without affecting short-term memory (STM) retention. Therefore, our findings indicate that the regulation of hippocampal mRNA translation is a major control step in memory consolidation. 相似文献
945.
Distinct ventral and dorsal hippocampus AP5 anxiolytic effects revealed in the elevated plus-maze task in rats 总被引:1,自引:0,他引:1
The hippocampal formation (HPC) mediates processes associated with learning, memory, anxiety and fear. The glutamate N-methyl-d-aspartate (NMDA)-receptor subtype is involved in many HPC functional processes related to learning and memory. Although not tested for the HPC, NMDA-receptor antagonists reduced fear and anxiety related responses when applied to other brain regions mediating defensive behaviour. Consequently, this study evaluated the effects of ventral or dorsal HPC application of the NMDA-receptor antagonist, AP5, in rats submitted to the Trial 1/Trial 2 elevated plus-maze (EPM) task. Ventral, but not dorsal, infusions of AP5 (6 and 24 nmol) before EPM Trial 1 increased open arms exploration and reduced risk assessment behavior, suggesting an anxiolytic-like effect. Furthermore, no interference in the avoidance responses was detected during EPM Trial 2 after AP5 infusion into the ventral or dorsal HPC before Trial 1, post-trial 1, or before Trial 2. These data support the notion of differential involvement of ventral HPC, but not dorsal, in mechanisms associated with anxiety and suggest the participation of the glutamatergic transmission, through NMDA receptor, into the ventral HPC in the mediation of defensive behavior. 相似文献
946.
Ráez M 《Journal of personality assessment》2007,89(Z1):S119-S123
This study is composed of 233 adult nonpatients, all from Peru. Inclusion/exclusion criteria are described. Interrater reliability statistics at the response level are presented along with scores for the Rorschach Comprehensive System (CS; Exner & Erdberg, 2005). Considering the results of this investigation, the researcher suggests a line of multicultural research. The differences between the United States and Peru strengthen the psychometric and qualitative value of this line of investigation. 相似文献
947.
Burgos JE 《Journal of the experimental analysis of behavior》2007,88(1):115-130
This article presents an interpretation of autoshaping, and positive and negative automaintenance, based on a neural-network model. The model makes no distinction between operant and respondent learning mechanisms, and takes into account knowledge of hippocampal and dopaminergic systems. Four simulations were run, each one using an A-B-A design and four instances of feedfoward architectures. In A, networks received a positive contingency between inputs that simulated a conditioned stimulus (CS) and an input that simulated an unconditioned stimulus (US). Responding was simulated as an output activation that was neither elicited by nor required for the US. B was an omission-training procedure. Response directedness was defined as sensory feedback from responding, simulated as a dependence of other inputs on responding. In Simulation 1, the phenomena were simulated with a fully connected architecture and maximally intense response feedback. The other simulations used a partially connected architecture without competition between CS and response feedback. In Simulation 2, a maximally intense feedback resulted in substantial autoshaping and automaintenance. In Simulation 3, eliminating response feedback interfered substantially with autoshaping and automaintenance. In Simulation 4, intermediate autoshaping and automaintenance resulted from an intermediate response feedback. Implications for the operant-respondent distinction and the behavior-neuroscience relation are discussed. 相似文献
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