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931.
Supporting teacher use of interventions: effects of response dependent performance feedback on teacher implementation of a math intervention 总被引:2,自引:0,他引:2
Donna Gilbertson Joseph C. Witt Lynn LaFleur Singletary Amanda VanDerHeyden 《Journal of Behavioral Education》2007,16(4):311-326
This study examined general education teachers’ implementation of a peer tutoring intervention for five elementary students
referred for consultation and intervention due to academic concerns. Treatment integrity was assessed via permanent products
produced by the intervention. Following verbal instructions, intervention implementation by four teachers was consistently
low or exhibited a downward trend whereas one teacher’s moderate implementation co-occurred with student gains. When classroom
training was conducted with four teachers exhibiting low integrity, all teachers improved implementation. After accurately
implementing the intervention for three training sessions with classroom training, response dependent performance feedback
was provided when teachers independently used the intervention below 100% integrity, as determined by review of permanent
products. With response dependent performance feedback, three of the four teachers implemented the intervention at levels
above the verbal training performance, whereas implementation for one teacher increased following discussion of an upcoming
school team meeting. Student math scores improved during intervention. 相似文献
932.
Withdrawal from cocaine self-administration produces long-lasting deficits in orbitofrontal-dependent reversal learning in rats 下载免费PDF全文
Calu DJ Stalnaker TA Franz TM Singh T Shaham Y Schoenbaum G 《Learning & memory (Cold Spring Harbor, N.Y.)》2007,14(5):325-328
Drug addicts make poor decisions. These decision-making deficits have been modeled in addicts and laboratory animals using reversal-learning tasks. However, persistent reversal-learning impairments have been shown in rats and monkeys only after noncontingent cocaine injections. Current thinking holds that to represent the human condition effectively, animal models of addiction must utilize self-administration procedures in which drug is earned contingently; thus, it remains unclear whether reversal-learning deficits caused by noncontingent cocaine exposure are relevant to addiction. To test whether reversal learning deficits are caused by contingent cocaine exposure, we trained rats to self-administer cocaine, assessed cue-induced cocaine seeking in extinction tests after 1 and 30 d of withdrawal, and then tested for reversal learning more than a month later. We found robust time-dependent increases in cue-induced cocaine seeking in the two extinction tests (incubation of craving) and severe reversal-learning impairments. 相似文献
933.
The point estimate of sample coefficient alpha may provide a misleading impression of the reliability of the test score. Because sample coefficient alpha is consistently biased downward, it is more likely to yield a misleading impression of poor reliability. The magnitude of the bias is greatest precisely when the variability of sample alpha is greatest (small population reliability and small sample size). Taking into account the variability of sample alpha with an interval estimator may lead to retaining reliable tests that would be otherwise rejected. Here, the authors performed simulation studies to investigate the behavior of asymptotically distribution-free (ADF) versus normal-theory interval estimators of coefficient alpha under varied conditions. Normal-theory intervals were found to be less accurate when item skewness >1 or excess kurtosis >1. For sample sizes over 100 observations, ADF intervals are preferable, regardless of item skewness and kurtosis. A formula for computing ADF confidence intervals for coefficient alpha for tests of any size is provided, along with its implementation as an SAS macro. 相似文献
934.
Contextual learning induces an increase in the number of hippocampal CA1 neurons expressing high levels of BDNF 总被引:3,自引:0,他引:3
Chen J Kitanishi T Ikeda T Matsuki N Yamada MK 《Neurobiology of learning and memory》2007,88(4):409-415
We examined behaviorally induced expression of brain-derived neurotrophic factor (BDNF) in area CA1 of the hippocampus. Sprague-Dawley rats were trained in a contextual fear conditioning (CFC) task, sacrificed 4h later, and their brains were processed for immunohistochemistry. We found distinctively high levels of BDNF immunoreactivity in a small number ( approximately 1%) of CA1 neurons in untrained animals. The number of these exceptional neurons, which are identified as BDNF(++) in this study, was increased by up to approximately 3% after CFC. This increase was blocked in the presence of a memory-impairing dose of a NMDA receptor antagonist (MK801 0.3 mg/kg, i.p.) given 30 min prior to training. The BDNF signal intensity in BDNF(++) neurons correlated with that of surrounding glutamic acid decarboxylase (GAD) 65. This correlation between GAD65 and BDNF signal intensities suggests that BDNF upregulation was associated with increased signaling via inhibitory GABAergic synapses that would lessen further intervening neuronal activity. Our observation that neurons which upregulate BDNF expression following a learning experience are rich in GAD65-enriched afferent synapses suggests that these neurons may have distinct roles in memory consolidation. 相似文献
935.
The present study examined the reliability and the construct validity of a questionnaire designed to measure the attitudes toward computers in everyday life. A total of 2,050 participants responded to the questionnaire. Confirmatory factor analysis suggests that attitudes toward computers are composed of three dimensions: sense of benefit, sense of dependence, and sense of harm. 相似文献
936.
This paper investigates whether social anxiety and loneliness lead to contrasting beliefs and preferences among cell phone users towards texting and talking on their cell phones. Three hypotheses are examined: (1) that social anxiety and loneliness are differentially associated with generalized preferences either for texting or for talking on the cell phone, (2) that these preferences are linked to contrasting beliefs concerning the social functionality of the short message service (SMS), and (3) that these divergent beliefs mediate the effects of social anxiety and loneliness on cell phone users' generalized preferences for texting or talking. Results from an Internet questionnaire (N=158) showed that, whilst lonely participants preferred making voice calls and rated texting as a less intimate method of contact, anxious participants preferred to text, and rated it a superior medium for expressive and intimate contact. These divergent beliefs accounted for 36% and 16% of the variance in preference for texting and voice calls, respectively, and significantly attenuated the influence of loneliness and social anxiety when they were added to the regression equations for these measures. Results are discussed in terms of the hyperpersonal possibilities of mobile communications technologies. 相似文献
937.
Looking-time studies examined whether 11-month-old infants can individuate two pairs of objects using only shape information. In order to test individuation, the object pairs were presented sequentially. Infants were familiarized either with the sequential pairs, disk-triangle/disk-triangle (XY/XY), whose shapes differed within but not across pairs, or with the sequential pairs, disk-disk/triangle-triangle (XX/YY), whose shapes differed across but not within pairs. The XY/XY presentation looked to adults like a single pair of objects presented repeatedly, whereas the XX/YY presentation looked like different pairs of objects. Following familiarization to these displays, infants were given a series of test trials in which the screen was removed, revealing two pairs of objects in one of two outcomes, XYXY or XXYY. On the first test trial, infants familiarized with the identical pairs (XY/XY) apparently expected a single pair to be revealed because they looked longer than infants familiarized with the distinct pairs (XX/YY). Infants who had seen the distinct pairs apparently expected a double pair outcome. A second experiment showed outcomes of a single XY pair. This outcome is unexpected for XX/YY-familiarized infants but expected for XY/XY-familiarized infants, the reverse of Experiment 1. This time looking times were longer for XX/YY infants. Eleven-month-olds appear to be able to represent not just individual objects but also pairs of objects. These results suggest that if they can group the objects into sets, infants may be able to track more objects than their numerosity limit or available working memory slots would normally allow. We suggest possible small exact numerosity representations that would allow tracking of such sets. 相似文献
938.
Sylvia Xiaohua Chen Michael Harris Bond Donghui Tang 《Asian Journal of Social Psychology》2007,10(4):213-223
In an attempt to explore the attitude-behaviour relationship, the present study examined the mixed findings from research on filial piety by differentiating filial attitudes from filial behaviours. The Filial Behaviour Scale was developed to tap the behavioural manifestations of filial piety, and its nomological network was established in two Chinese contexts, Hong Kong and Beijing. In addition to filial attitudes, we used values, social beliefs, and self-construals to explain filial behaviours. The results of hierarchical regression analysis showed that the value factor of conservation and the social axiom of reward for application predicted filial behaviour above and beyond filial attitudes; an interdependent self-construal moderated the effect of cultural group on filial behaviour. Gender and regional differences in filial piety were also examined. Males were found to score higher on filial attitudes, but not significantly higher on filial behaviours. Regional differences existed in filial behaviours, but not in filial attitudes, with Mainland Chinese displaying a higher level of filial behaviours than their Hong Kong counterparts. These identified differences suggest the importance of differentiating filial attitudes from filial behaviours in future attempts to understand Chinese filiality. 相似文献
939.
940.
儿童早期词汇获得的词类差 总被引:1,自引:1,他引:0
儿童早期词汇获得存在词类差异,很多语言中名词比例都要高于其他词类,因此一些研究者提出“名词优势”理论。但是,一些对汉语和韩语的研究发现,儿童早期获得的动词比例与名词没有显著差异,甚至高于名词,同时汉语和韩语动词比例也远大于英语动词比例。针对不同语言儿童早期获得的动、名词比例差异现象,研究者认为语言结构特征和成人对孩子的言语输入可以解释不同语言儿童早期词汇中动、名词比例的差异,其中成人言语中词类的频率、单词位置、词形变化复杂性和语用等因素都会影响儿童早期词汇获得。此外,不同的词汇测量方法、观察情境、词类定义、词汇量水平、单词理解与说出也会造成不同研究结果之间的差异 相似文献