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51.
Training chicks (Gallus domesticus) on a one-trial passive avoidance task results in transient and time-dependent enhanced increases in N-methyl-d-aspartate- or alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate-stimulated intracellular calcium concentration in synaptoneurosomes isolated from a specific forebrain region, the intermediate medial hyperstriatum ventrale. This increase could result from either calcium entry from the extracellular medium or from mobilization of intracellular calcium stores. We have therefore examined the effects of dantrolene, an inhibitor of calcium release from the intracellular ryanodine-sensitive store, on these processes. Dantrolene, 50 nmol per hemisphere injected intracerebrally 30 min pre- or 30 min posttraining, blocked longer term memory for the passive avoidance task, whereas memory for the task was unaffected when dantrolene was injected at earlier or later times. Preincubation of synaptoneurosomes, isolated from the intermediate hyperstriatum ventrale 10 min after training, with 100 nM dantrolene abolished the enhanced training-induced increase in intracellular calcium concentration elicited by 0.5 mM N-methyl-d-aspartate. By contrast, the training-induced enhancement of the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate-stimulated increase in intracellular calcium concentration in synaptoneurosomes prepared 6 h posttraining was unaffected by preincubation with dantrolene, which was not amnestic at this time. Calcium release from ryanodine-sensitive intracellular stores may thus be a necessary stage in the early phase of the molecular cascade leading to the synaptic modulation required for long-term memory storage.  相似文献   
52.
The media remains a powerful presence in U.S. culture. It gives people news of world and local events, it entertains, and it may even function as a companion to children. Because it functions as a window to the outside world, what appears across its landscape actually may become people's reality. Thus, the potential for distorting their view of that world is high if the picture provided is unrepresentative of actual events. For example, the prevalence of violent acts on television has been linked to increased aggression and escalating impressions of a dangerous world, and the overrepresentation of youth and beauty may be a causal factor of eating disorders. In this article, we explore the possibility that the media may also serve as a powerful creator of the very public opinions it seeks to reflect in its news. Subtle nonverbal cues of newscasters have been shown to influence voting behavior, and the media's overrepresentation of the proportion of blacks in poverty may decrease whites' support of welfare. By portraying a world in which people's opinions are based on their ethnic or demographic group membership, the media may also subtly but powerfully create the very opinions they seek to reflect.  相似文献   
53.
Two experiments investigated differences between active and passive participation in a computer-generated virtual environment in terms of spatial memory, object memory, and object location memory. It was found that active participants, who controlled their movements in the virtual environment using a joystick, recalled the spatial layout of the virtual environment better than passive participants, who merely watched the active participants' progress. Conversely, there were no significant differences between the active and passive participants' recall or recognition of the virtual objects, nor in their recall of the correct locations of objects in the virtual environment. These findings are discussed in terms of subject-performed task research and the specificity of memory enhancement in virtual environments.  相似文献   
54.
There has been an increasing focus on family involvement in the treatment of children with serious emotional disorders, but it has received only limited attention in relation to out-of-home placements. I present the findings from a qualitative study of family involvement from the perspectives of parents whose children were placed in therapeutic foster care (TFC). Parents' perspectives on their involvement in placement decisions, relationships with professionals and TFC providers, practices related to family involvement, barriers to involvement, and strategies to enhance family involvement are described. Parents of children in TFC wanted to have contact with their children and to participate in decision making. They described relationships and practices that contributed to their involvement.  相似文献   
55.
The functional role of NCAM gene expression in memory formation was studied in the one-trial passive avoidance task in day-old chicks by pretraining injections of one of three different 18-mer end-protected oligonucleotides corresponding to positions 190-, 207-, and 332- of the NCAM Ig1 domain. Twenty-four-hour-old chicks were trained by pecking at a bitter-tasting bead and tested for avoidance 30 min, 3, 8, or 24 hr later. Memory retention was significantly reduced only in the group of animals injected with the NCAM antisense corresponding to position 207- (AS-ODN-207), and only if given twice, both immediately after hatching and 12 hr before training. This antisense was without effect on the general behavior of the chicks, training or acquisition, and did not produce observable neurotoxic damage. Under such conditions amnesia was evident by 3 hr after training and lasted until at least 24 hr after training. The two other tested oligonucleotides were without behavioral effect. To control for nonsequence-specific effects of AS-ODN-207, brains from injected and trained animals were processed for Western blotting and probed using anti-NCAM, anti-L1, and anti-actin antibodies. NCAM antisense corresponding to position 207- significantly reduced the level of NCAM, whereas the level of L1 and actin remained unchanged. These results confirm our earlier conclusion that NCAM is necessary for longer term memory retention.  相似文献   
56.
Development and utilization of two self-efficacy measures thought to be relevant to stressed family caregivers, Caregiver Self-Care Self-Efficacy and Caregiver Problem-Solving Self-Efficacy, are described. Data obtained in the context of a psychoeducational intervention program are available for 217 caregivers of frail and/or cognitively impaired elders. Analyses of psychometric properties of the efficacy measures demonstrate good internal consistency and test-retest reliability for both measures. In addition, both measures of self-efficacy are related to depression as measured by the Beck Depression Inventory and caregiver distress as measured by the Zarit Burden Scale. Problem-Solving Self-efficacy also is related to subjective caregiver burden as measured by Zarit's Memory and Behavior Problem Checklist. Results are promising in terms of the utility of the measure and the application of self-efficacy theory to the caregiving situation. Limitations of these measures are discussed and suggestions made for improved second-generation self-efficacy scales.  相似文献   
57.
58.
Autobiographical memories are characterised by a range of emotions and emotional reactions. Recent research has demonstrated that differences in emotional valence (positive vs. negative emotion) and arousal (the degree of emotional intensity) differentially influence the retrieved memory narrative. Although the mnemonic effects of valence and arousal have both been heavily studied, it is currently unclear whether the effects of emotional arousal are equivalent for positive and negative autobiographical events. In the current study, multilevel models were used to examine differential effects of emotional valence and arousal on the richness of autobiographical memory retrieval both between and within subjects. Thirty-four young adults were asked to retrieve personal autobiographical memories associated with popular musical cues and to rate the valence, arousal and richness of these events. The multilevel analyses identified independent influences of valence and intensity upon retrieval characteristics at the within- and between-subject levels. In addition, the within-subject interactions between valence and arousal highlighted differential effects of arousal for positive and negative memories. These findings have important implications for future studies of emotion and memory, highlighting the importance of considering both valence and arousal when examining the role emotion plays in the richness of memory representation.  相似文献   
59.
The purpose of the present study was to assess the potential of exergame training based on physically simulated sport play as a mode of physical activity that could have cognitive benefits for older adults. If exergame play has the cognitive benefits of conventional physical activity and also has the intrinsic attractiveness of video games, then it might be a very effective way to induce desirable lifestyle changes in older adults. To examine this issue, the authors developed an active video game training program using a pretest-training-posttest design comparing an experimental group (24 × 1 hr of training) with a control group without treatment. Participants completed a battery of neuropsychological tests, assessing executive control, visuospatial functions, and processing speed, to measure the cognitive impact of the program. They were also given a battery of functional fitness tests to measure the physical impact of the program. The trainees improved significantly in measures of game performance. They also improved significantly more than the control participants in measures of physical function and cognitive measures of executive control and processing speed, but not on visuospatial measures. It was encouraging to observe that, engagement in physically simulated sport games yielded benefits to cognitive and physical skills that are directly involved in functional abilities older adults need in everyday living (e.g., Hultsch, Hertzog, Small, & Dixon, 1999).  相似文献   
60.
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