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971.
This study examined the effect of different types of feedback on goal orientation, perception of motivational climate, satisfaction, and boredom in physical education (PE) classes, pupils' preferences for challenging versus easy tasks, pupils' attitudes towards PE lessons, and perception of gymnastic ability. 95 subjects in three treatment conditions (positive feedback, negative feedback, and both feedback types) participated in 14 lessons and completed pre- and postintervention measures. Results showed that subjects in the positive feedback group had significantly higher scores on learning-oriented motivational climate and enjoyment than the subjects of the negative feedback group. The negative feedback group reported higher scores on performance-oriented motivational climate than the positive feedback group. Results also showed that subjects in the group receiving both types of feedback had lower scores on learning-oriented motivational climate, higher scores on enjoyment than the negative feedback group, and lower scores on boredom than the positive feedback group. The effects of feedback on physical education students' motivation are discussed. 相似文献
972.
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
973.
Executive functions include abilities of goal formation, planning, carrying out goal-directed plans, and effective performance.
This article aims at reviewing some of the current knowledge surrounding executive functioning and presenting the contrasting
views regarding this concept. The neural substrates of the executive system are examined as well as the evolution of executive
functioning, from development to decline. There is clear evidence of the vulnerability of executive functions to the effects
of age over lifespan. The first executive function to emerge in children is the ability to inhibit overlearned behavior and
the last to appear is verbal fluency. Inhibition of irrelevant information seems to decline earlier than set shifting and
verbal fluency during senescence. The sequential progression and decline of these functions has been paralleled with the anatomical
changes of the frontal lobe and its connections with other brain areas. Generalization of the results presented here are limited
due to methodological differences across studies. Analysis of these differences is presented and suggestions for future research
are offered. 相似文献
974.
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
975.
Ligia M. Chavez Leida Matías-Carrelo Concepcion Barrio Glorisa Canino 《Journal of child and family studies》2007,16(1):72-86
We reviewed the Spanish translation of the Youth Quality of Life Instrument-Research Version (YQOL-R) and culturally adapted
the measure with Puerto Rican and Mexican American children and adolescents. The YQOL-R is a self-reported measure that includes
four domains: Sense of Self, Social Relationships, Environment, and General Quality of Life. A total of 10 focus groups were
conducted with children aged 9 to 11, adolescents aged 12 to 17, their parents, and mental health providers. Five focus groups
were conducted in San Diego, California and five in San Juan, Puerto Rico. Eligible participants were recruited from children’s
outpatient psychiatry clinics. We followed an iterative and recursive process in reviewing changes and modifications to the
instrument using a bilingual committee and a Multi National Bilingual Committee. Greater semantic, content, and technical
equivalence of the Spanish and English versions for the YQOL-R was achieved for the two largest U.S. Latino subgroups: Mexican
Americans and Puerto Ricans. The cultural adaptation process revealed several important issues regarding the measurement of
quality of life in different age groups. Additional items for school, relationships (both family and friends) and spare time
suggested the need for a future children’s version of the instrument. For the adolescents, additional items were suggested
in the areas of sexuality, intergenerational conflict and acculturative stress. 相似文献
976.
María Isabel Peralta-Ramírez A. Verdejo M. A. Muñoz J. M. Sabio J. F. Jiménez-Alonso M. Pérez-García 《Journal of clinical psychology in medical settings》2007,14(4):344-350
The goal of this study was to develop a simple, easy, and quick self-report measure, the Lupus Symptom Inventory (LSI), designed
to evaluate subjective symptoms of Systemic Lupus Erythematosus (SLE). The internal consistency of the LSI was tested, as
well as its concordance with physician reports and serological indicators of disease activity by evaluating the self-reports
of 46 patients with SLE who completed the LSI daily for a one-month period. Throughout this one-month period, parameters of
serological activity and routine medical check-up were obtained. The results showed a high internal consistency of the LSI,
with a Cronbach alpha of .86. Additionally, a contingency analysis showed agreement between medical report and patient self-report
on the same day for six of seven lupus symptoms (difficulty breathing (p < .004), joint pain (p < .001), loss of appetite (p < .003), general malaise (p < .005), fatigue (p < .005), and skin rash (p < .018)) but not for abdominal symptoms. Finally, differences were found between LSI scores of patients with high versus
low serological activity (χ2(1) = 5.302; p < .021), with the former presenting higher LSI scores than the latter. These results show that the LSI may be a reliable
and valid instrument for evaluating the subjective symptoms of the disease as well as its fluctuations. 相似文献
977.
Forcato C Burgos VL Argibay PF Molina VA Pedreira ME Maldonado H 《Learning & memory (Cold Spring Harbor, N.Y.)》2007,14(4):295-303
The reconsolidation hypothesis states that a consolidated memory could again become unstable and susceptible to facilitation or impairment for a discrete period of time after a reminder presentation. The phenomenon has been demonstrated in very diverse species and types of memory, including the human procedural memory of a motor skill task but not the human declarative one. Here we provide evidence for both consolidation and reconsolidation in a paired-associate learning (i.e., learning an association between a cue syllable and the respective response syllable). Subjects were given two training sessions with a 24-h interval on distinct verbal material, and afterward, they received at testing two successive retrievals corresponding to the first and second learning, respectively. Two main results are noted. First, the first acquired memory was impaired when a reminder was presented 5 min before the second training (reconsolidation), and also when the second training was given 5 min instead of 24 h after the first one (consolidation). Second, the first retrieval proved to influence negatively on the later one (the retrieval-induced forgetting [RIF] effect), and we used the absence of this RIF effect as a very indicator of the target memory impairment. We consider the demonstration of reconsolidation in human declarative memory as backing the universality of this phenomenon and having potential clinical relevance. On the other hand, we discuss the possibility of using the human declarative memory as a model to address several key topics of the reconsolidation hypothesis. 相似文献
978.
Experiences with a high emotional content (aversive) tend to be stored as long-term memories; however, there are also contextual recollections, which form a significant part of our memories. Different research has shown that the insular cortex (IC) plays an important role during aversive memory formation, yet its role during incidental/non-aversive learning like pre-exposure contextual memory formation has received little attention. The objective of this research was to establish the role of cholinergic activity in the IC through its muscarinic receptors during the formation of inhibitory avoidance (IA) memory, as well as during pre-exposure contextual memory, using a paradigm such as latent inhibition (LI). Rats with bilateral cannulae directed into the IC were trained in the LI paradigm of IA or IA task alone. The muscarinic antagonist receptor scopolamine was infused bilaterally into the IC 5 min before the pre-exposure into the dark chamber of the IA cage, one day before the conventional IA training or during the IA training day. During the IA test, the entrance latency into the dark chamber of the IA cage was measured as an index of contextual memory. The results showed that scopolamine infused before and after IA training disrupts inhibitory avoidance memory. Also, it showed that the pre-exposed saline-infused animals (LI) had a lower entrance latency compared to the group not pre-exposed (IA). However, the group that received scopolamine into the IC before, but not after, the pre-exposure to the dark chamber, presented a similar latency to the IA group, showing a blockade of the latent inhibition of the IA. These results suggest that cholinergic activity in the insular cortex is necessary during the acquisition and consolidation of avoidance memory, but appears necessary only during the acquisition of pre-exposure non-aversive contextual memory. 相似文献
979.
Andero R Torras-Garcia M Quiroz-Padilla MF Costa-Miserachs D Coll-Andreu M 《Neurobiology of learning and memory》2007,87(4):510-521
The pedunculopontine tegmental nucleus (PPTg) is involved in the regulation of thalamocortical transmission and of several functions related to ventral and dorsal striatal circuits. Stimulation of the PPTg in anesthetized animals increases cortical arousal, cortical acetylcholine release, bursting activity of mesopontine dopaminergic cells, and striatal dopamine release. It was hypothetized that PPTg stimulation could improve learning by enhancing cortical arousal and optimizing the activity of striatal circuits. We tested whether electrical stimulation (ES) of the PPTg, applied to freely-moving awake rats previously implanted with a chronic electrode, would improve the acquisition and/or the retention of two-way active avoidance conditioning, and whether this effect would depend on the specific PPTg region stimulated (anterior vs posterior) and on the time of ES: just before (pre-training) or after (post-training) each of three training sessions. The treatment consisted of 20 min of ES (0.2 ms pulses at 100 Hz; current intensity: 40-80 microA). The results showed that (1) this stimulation did not induce either any signs of distress nor abnormal behaviors, apart from some motor stereotyped behaviors that disappeared when current intensity was lowered; (2) pre-training ES applied to the anterior PPTg improved the acquisition of two-way active avoidance, (3) no learning improvement was found after either post-training ES of the anterior PPTg, or pre- and post-training ES of the posterior PPTg. The results give support to a role of PPTg in learning-related processes, and point to the existence of functional PPTg regions. 相似文献
980.
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