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121.
Transformations of hand movements by tools such as levers or electronic input devices can invoke performance costs compared to untransformed movements. This study investigated by means of the Psychological Refractory Period (PRP) paradigm at which stage of information processing such tool-transformation costs arise. We used an inversion transformation, that is, the movement of the operating hand was transformed into a spatially incompatible movement of a lever. As a basic tool-transformation effect, the initiation of inverted tool movements was delayed compared to noninverted movements. Experiment 1 suggested a central (or postcentral) locus of this tool-transformation effect and ruled out a (precentral) perceptual locus. Experiments 2 and 3 confirmed the central locus and ruled out a later, motor-related stage of processing. The results show that spatially incompatible tool movements delay a capacity-limited stage of information processing, often referred to as response selection.  相似文献   
122.
Objective: The authors evaluated the time course of the treatment effect of Osmotic-Release Oral System methylphenidate (OROS(?) MPH) HCl (Concerta(?), Raritan, NJ) CII in children with ADHD. Method: Data were combined from two double-blind, randomized, placebo-controlled, cross-over, analog classroom studies in children (9-12 years) with ADHD. Participants received an individualized dose of placebo or OROS(?) MPH on two laboratory school days. Permanent Product Math Test and Swanson, Kotkin, Agler, M-Flynn, and Pelham scores were evaluated 0.5 hr before dosing and 1, 2, 4, 10, 11, and 12.5 hr post dose. Analysis used a repeated-measures mixed model. Results: Treatment effects were present at all postdose assessment points (p < .0001 for all comparisons, n = 139). Adverse events were similar to previous reports for OROS(?) MPH. Conclusion: A robust treatment effect occurred with OROS(?) MPH; onset was at 1 hr and persisted for at least 12.5 hr after dosing.  相似文献   
123.
Stress, depending on intensity and duration, elicits adaptive or maladaptive physiological effects. Increasing evidence shows those patterns of advantageous versus deleterious physiologic stress effects also exist for some brain functions, including learning and memory. For example, short stress enhances, while chronic stress impairs, performance on numerous cognitive tasks in male rats. In contrast, performance of female rats is enhanced, or not altered, following both short-term and long-term stress exposure on the same behavioral tasks. The current study was designed to better characterize the behavioral effects of sustained chronic restraint stress in female rats. Female Sprague Dawley rats were assigned to a stress (restraint, 6 h/day, 35 days) or control (no stress) condition, weighed weekly, and then tested on open field (OF), object recognition (OR) and object placement (OP) tasks. Stressed females gained less weight during stress than controls. On the OF, there were no group differences in locomotor activity, but stressed females made fewer inner visits than controls, indicating increased anxiety. Both groups successfully performed the OP and OR tasks across all inter-trial delays, indicating intact non-spatial and spatial memory in both control and stress females. The current results provide preliminary evidence that the commonly used chronic restraint stress model may not be an efficient stressor to female rats.  相似文献   
124.
This research examined the relation between mothers' responses to children's questions about interparent conflict and children's adjustment. Participants were 134 mothers and their children (70 boys, 64 girls), aged 7 to 10. In each family, an act of intimate-partner violence (IPV) had recently occurred. Mothers' responses to children's questions about interparent conflict were assessed via a semistructured interview coded to reflect the extent to which the mothers' responses addressed the content of the children's questions. Mothers and children reported on physical IPV. Mothers also reported on interparent conflict, parent-child aggression, and maternal warmth. Children's adjustment was assessed via mothers' and children's reports at two time points 6 months apart. The extent to which mothers' responses addressed the content of the children's questions about interparent conflict was negatively associated with children's adjustment problems, after accounting for the frequency of physical IPV, frequency of interparent conflict, parent-child aggression, and maternal warmth. These associations emerged cross-sectionally and prospectively. However, in those prospective analyses that accounted for children's baseline levels of adjustment, maternal responsiveness was not associated with later children's adjustment problems.  相似文献   
125.
Mammalian target of rapamycin (mTOR), a central regulator of protein synthesis in neurons, has been implicated in synaptic plasticity and memory. Here we show that mTOR inhibition by rapamycin in the basolateral amygdala (BLA) or dorsal hippocampus (DH) impairs both formation and reconsolidation of memory for inhibitory avoidance (IA) in rats. Male Wistar rats received bilateral infusions of vehicle or rapamycin into the BLA or DH before or after IA training or retrieval. Memory retention was tested at different time points after drug infusion. Rapamycin impaired long-term IA retention when given before or immediately after training or retrieval into the BLA. When infused into the DH, rapamycin produced memory impairment when given before training or immediately after retrieval. The impairing effects of post-retrieval rapamycin required memory retrieval and were not reversed by a reminder shock. The results provide the first evidence that mTOR in the BLA and DH might play a role in IA memory reconsolidation.  相似文献   
126.
The study examines whether self-efficacy mediates between intention and behavior, and whether appearance norms and self-efficacy are additive or synergistic predictors of sunscreen use. At two measurement points in time, 14 weeks apart, 154 individuals responded to an online questionnaire. Moderated mediation was tested by hierarchical regression analyses. Self-efficacy mediated the intention-behavior relationship, whereas appearance norms emerged as a moderator of the self-efficacy-sunscreen use relationship. The model accounted for 22% of the behavior variance at time 2. For individuals who believe that they would look more attractive with a tan, self-efficacy did not have a strong effect on behavior. Thus, for skin-protection motivation to become effective, self-efficacy is needed in conjunction with less positive appearance norms. Implications for public health promotion and mass media sunscreen use campaigns are discussed.  相似文献   
127.
Although the number of patients needing organ transplantation systematically increases, recent years have seen a considerable shortage of donors. The level of knowledge and attitudes toward donation are critical factors in achieving the required balance between supply and demand. This pilot study assessed the knowledge, opinions, and behaviors related to organ donation and transplantation among 625 students representing eight different fields of study from the University of Rzeszow in south-eastern Poland. Although the participants provided evidence of knowledge about human organ donation and transplantation, they were aware of the main organs of the human body for potential transplants, and generally showed positive attitudes; only 24% of the subjects indicated their willingness to register as a donor; only 3% stated that they had already registered and had a donor card. The findings suggest that good intentions do not translate into action and that Poland needs to develop a nation-wide, up-to-date, and youth-oriented health education program that builds on favorable attitudes toward organ donation and transplantation.  相似文献   
128.
Hemophilia A and B are X-linked recessive inherited bleeding disorders that have a profound impact on the family of affected individuals. Education is vital to enable women to appreciate the implications of being a carrier and the implications for a prospective child. Prior research has shown that cultural, socio-economic and linguistic issues in South Africa are major barriers to communication for first-language Xhosa-speakers. This exploratory study aimed to investigate the basic knowledge of genetic inheritance among this cultural group in order to promote culturally-sensitive, effective genetic counseling. Ten in-depth interviews were conducted with Xhosa-speaking mothers or caregivers of boys with hemophilia. Results suggest that the participants had a very limited understanding of the clinical management, genetic consequences and cause of hemophilia. While treatment and care by health care service providers was fully accepted, several participants believed that traditional methods would provide them with more satisfactory explanations. These findings suggest that there is a critical need for socio-culturally tailored, language-specific education for families with hemophilia.  相似文献   
129.
130.
This study examined in a Spanish population the developmental pattern of digit span, as an index of one of the components of Baddeley's working memory--the phonological loop. A verbal digit span was administered to 570 participants ranging from 5 to 17 years old. The results indicated that the digit memory span increases until age 17 as opposed to Anglo-Saxon data--where it is established that this span reaches a peak by age 15. Additionally, these results were compared to the performance in the same task of healthy elderly, Alzheimer disease patients, and Frontotemporal dementia patients, examined in a previous study. The analysis shows that the phonological loop is affected by age and not so much by dementias.  相似文献   
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