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961.
Past research suggests that children begin to phonologically rehearse at around 7 years of age. Less is known regarding the development of refreshment, an attention-based maintenance mechanism. Therefore, the use of these two maintenance methods by 6- and 8-year-olds was assessed using memory span tasks that varied in their opportunities for maintenance activity. Experiment 1 showed that nonverbal processing impaired both groups’ performance to similar extents. Experiment 2 employed phonologically similar or dissimilar memory items and compared the effects of verbal versus nonverbal processing on recall. Both groups showed evidence of phonological maintenance under nonverbal processing but not under verbal processing. Furthermore, nonverbal processing again impaired recall. Verbal processing was also more detrimental to performance in 8-year-olds than in 6-year-olds. Together, the results suggest that nonverbal processing impairs recall by obstructing refreshment and that developmental change in maintenance between 6 and 8 years of age consists primarily of an increase in phonological rehearsal.  相似文献   
962.
It remains unclear what is being processed in blindsight in response to faces, colours, shapes, and patterns. This was investigated in two hemianopes with chromatic and achromatic stimuli with sharp or shallow luminance or chromatic contrast boundaries or temporal onsets. Performance was excellent only when stimuli had sharp spatial boundaries. When discrimination between isoluminant coloured Gaussians was good it declined to chance levels if stimulus onset was slow. The ability to discriminate between instantaneously presented colours in the hemianopic field depended on their luminance, indicating that wavelength discrimination totally independent of other stimulus qualities is absent. When presented with narrow-band colours the hemianopes detected a stimulus maximally effective for S-cones but invisible to M- and L-cones, indicating that blindsight is mediated not just by the mid-brain, which receives no S-cone input, or that the rods contribute to blindsight. The results show that only simple stimulus features are processed in blindsight.  相似文献   
963.
Children with ADHD are often non-compliant with parental instructions. Various methods have been used to reduce problem behaviors in these children, with medication and manipulation of behavioral contingencies being the most prevalent. An objection often raised by parents is that these management strategies require them to impose external control on the children which not only results in the children not learning self-control strategies, but also does not enhance positive interactions between them and their parents. Studies have shown that providing mindfulness training to parents, without a focus on reducing problem behaviors, can enhance positive interactions with their children and increase their satisfaction with parenting. We were interested to see what effects giving mindfulness training to two mothers, and subsequently to their children, would have on compliance by the children. Using a multiple baseline across mothers and children design, we found that giving a mother mindfulness training enhanced compliance by her child. When the children were subsequently given similar training, compliance increased even more markedly, and was maintained during follow-up. The mothers reported associated increases in satisfaction with the interactions with their children and happiness with parenting. We suspect that the mindfulness training produces personal transformations, both in parents and children, rather than teaching strategies for changing behavior.  相似文献   
964.
Many species have been shown to encode multiple sources of information to orient. To examine what kinds of information animals use to locate a goal we manipulated cue rotation, cue availability, and inertial orientation when the food-storing Clark’s nutcracker (Nucifraga columbiana) was searching for a hidden goal in a circular arena. Three groups of birds were used, each with a different goal–landmark distance. As the distance between the goal and the landmark increased, nutcrackers were less accurate in finding the correct direction to the goal than they were at estimating the distance (Experiment 1). To further examine what cues the birds were using to calculate direction, the featural cues within the environment were rotated by 90° and the birds were either oriented when searching (Experiments 2 and 3) or disoriented (Experiment 3). In Experiment 4, all distinctive visual cues were removed (both internal and external to the environment), a novel point of entry was used and the birds were either oriented or disoriented. We found that disorienting the nutcrackers so that they could not use inertial cues did not influence the birds’ total search error. The birds relied heavily but not completely on cues within the environment, as rotating available cues caused them to systematically shift their search behavior. In addition, the birds also relied to some extent on Earth-based cues. These results show the flexible nature of cue use by the Clark’s nutcracker. Our study shows how multiple sources of spatial information may be important for extracting multiple bearings for navigation.  相似文献   
965.
The goal of this study was to determine whether verbal interactions between mothers and their 6-month-old infants during media exposure ('media verbal interactions') might have direct positive impacts, or mitigate any potential adverse impacts of media exposure, on language development at 14 months. For 253 low-income mother-infant dyads participating in a longitudinal study, media exposure and media verbal interactions were assessed using 24-hour recall diaries. Additionally, general level of cognitive stimulation in the home [StimQ] was assessed at 6 months and language development [Preschool Language Scale-4] was assessed at 14 months. Results suggest that media verbal interactions play a role in the language development of infants from low-income, immigrant families. Evidence showed that media verbal interactions moderated adverse impacts of media exposure found on 14-month language development, with adverse associations found only in the absence the these interactions. Findings also suggest that media verbal interactions may have some direct positive impacts on language development, in that media verbal interactions during the co-viewing of media with educational content (but not other content) were predictive of 14-month language independently of overall level of cognitive stimulation in the home.  相似文献   
966.
Alan  Hájek 《Analysis》2005,65(286):112-119
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967.
The role of depression symptoms in dialysis withdrawal.   总被引:3,自引:0,他引:3  
Among end-stage renal disease (ESRD) patients on hemodialysis, death from withdrawal from life-sustaining dialysis is increasingly common. The present study's objective was to examine depression as a potential risk factor for hemodialysis withdrawal. Two hundred forty ESRD hemodialysis (133 male and 107 female) patients were followed for an average of 4 years after depression symptom assessment. Of these, 18% withdrew from dialysis. Using multivariate survival analysis and after controlling for the effects of age (p < .001) and clinical variables, the authors found that level of depression symptoms was a unique and significant predictive risk factor for the subsequent decision to withdraw from dialysis (p < .05). The potential impact that depression may have on the decision to withdraw from hemodialysis should be considered by health care providers, patient families, and patients.  相似文献   
968.
This longitudinal, year‐long study compared sleep–wake state organization in two groups of infants–infants whose mothers abused substances during their pregnancies and nonexposed, typically developing, age‐matched comparison infants–to determine whether differences in sleep–wake state organization existed between the two groups. Seventeen infants of mothers who were participating in a parent–infant residential treatment program for substance abuse were enrolled. Their sleep–wake state organization over the first year of life was compared to that of 17 age‐matched comparison infants. The intent was to follow each infant on five occasions over the first year of life using established methods of time‐lapse videosomnography to record sleep–wake state organization; however, attrition in the substance‐abusing group was problematic. Some sleep–wake variables (i.e., Active Sleep%, Quiet Sleep%, Awake%, number of nighttime awakenings) were similar for both groups of infants at comparable ages across the first year. Total sleep time and the longest sustained sleep period (sleep continuity variables) differed significantly at some of the ages measured. Although overall sleep architecture appears highly resilient and well organized, some indications of sleep fragmentation and shortened nighttime sleep periods were observed in the substance‐exposed infants. More research is needed to explain why sleep‐continuity variables and not sleep‐state proportion variables differed between the two groups.  相似文献   
969.
970.
This research explores the influence of consumers’ body‐related information on beliefs and purchase intentions toward products for which the consumption experience is significantly and directly determined by body‐related information (e.g., feel, fit, sense of safety) when the products are bought in body‐absent purchase environments such as the Internet. We examine the effects of consumers’ body esteem (i.e., like or dislike of one's body) and body boundary aberration (variation in the perceived location of the edges of one's body) in the context of apparel purchases that are made on the Internet. Body esteem had a positive influence on involvement with apparel, and body boundary aberration had a negative influence on consumers’ overall concern with the fit of apparel. Involvement with apparel and overall concern with fit, in turn, significantly influenced consumers’ intentions to purchase apparel online. Consequently, consumers with high body esteem were less likely to buy on the Internet and those with high body boundary aberration were more likely to buy.  相似文献   
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