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991.
Visuospatial learning and memory impairments are an early marker for age-related cognitive decline and Alzheimer's disease. Similar to humans, aged dogs show visuospatial learning and memory deficits (). One hundred and nine beagle dogs ranging between 0.25 and 11.99 years were tested on a visuospatial delayed non-matching to position (DNMP) task to better characterize the progression of visuospatial deficits in the dog. Age predicted 48.2% of the variability in learning the DNMP, with dogs ranging from 1 to 11.99 years generally making more errors with increasing age. By contrast, puppies (<1 year) likely were showing developmental deficits, possibly due to an immature prefrontal cortex. Mild visuospatial deficits were detected by 6 years, which precedes the typical onset of amyloid-beta (Abeta) accumulation in the dog brain by two years, and can serve as an early marker for cognitive decline in the dog. These findings suggest that (1) age-related changes in visuospatial function in the dog models that seen in humans, further validating the dog as a model for human aging and dementia; and (2) other mechanisms, such as oxidative stress, soluble Abeta oligomers or cholinergic deficits, are likely contributing to the early impairment.  相似文献   
992.
The report from President George W. Bush’s New Freedom Commission on Mental Health (NFC), Achieving the Promise: Transforming Mental Health Care in America(2003), proposes goals and recommendations for improving mental health services. This report has significant implications for the delivery of mental health services through the schools. A focused discussion of the potential opportunities and challenges of implementing NFC recommendations related to school-based mental health is presented. Strategies for addressing five key areas at the intersection of school mental health and the Commission’s recommendations include: stigma reduction, suicide prevention, expansion and improvement of school mental health, and screening and treatment of co-occurring mental health and substance abuse disorders.  相似文献   
993.
Prior research (DeLoache, Uttal & Rosengren, 2004) has documented that 18- to 30-month-olds occasionally make scale errors: they attempt to fit their bodies into or onto miniature objects (e.g. a chair) that are far too small for them. The current study explores whether scale errors are limited to actions that directly involve the child's body. We investigated whether children would also make scale errors with a doll and objects that were much too small for the doll (e.g. a chair, a bed). Many participants did try to fit the doll into or onto the miniature objects. Thus, the previously documented phenomenon of scale errors extends to situations in which the relevant size difference is between two objects. This finding supports the view that scale errors occur when visual information about object size fails to influence the decision to act on an object. The results are discussed in terms of the use of visual information for the planning and control of actions.  相似文献   
994.
Encoding fluency (how rapidly one generates a mediator for a new association) may be a cue used to judge one's own learning. To evaluate age differences in utilization of this cue, older and younger adults were instructed to use interactive imagery to study paired associates, pressing a button to indicate when an image had been formed for a given pair. A judgment of learning (JOL) was also made immediately after each pair had been studied. Hence, at least two cues pertaining to encoding fluency-whether an image had been formed (a diagnostic cue) and the latency of formation (a nondiagnostic one)-were available when making JOLs. Age equivalence was found in JOL accuracy, and JOLs for both age groups were positively related to imagery formation and were negatively related to the latency of image formation. Moreover, subjectively judged latency correlated higher with JOLs than actual (objective) latency, supporting the hypothesis that perceived fluency is a cue used in constructing JOLs.  相似文献   
995.
We present the results of two experiments that probe the ability of rhesus macaques to match visual arrays based on number. Three monkeys were first trained on a delayed match-to-sample paradigm (DMTS) to match stimuli on the basis of number and ignore continuous dimensions such as element size, cumulative surface area, and density. Monkeys were then tested in a numerical bisection experiment that required them to indicate whether a sample numerosity was closer to a small or large anchor value. Results indicated that, for two sets of anchor values with the same ratio, the probability of choosing the larger anchor value systematically increased with the sample number and the psychometric functions superimposed. A second experiment employed a numerical DMTS task in which the choice values contained an exact numerical match to the sample and a distracter that varied in number. Both accuracy and reaction time were modulated by the ratio between the correct numerical match and the distracter, as predicted by Weber's Law.  相似文献   
996.
  • This paper describes a study in the psychology of market mavenism, the consumer tendency to become especially involved in the marketplace. The purpose was to investigate empirically associations with the important consumer characteristics of innovativeness, status consumption, and need for uniqueness. The findings support the notion that market mavenism is due less to the demographic characteristics of consumers as it is more a socially constructed phenomenon. Global innovativeness, status consumption, and creative choice counterconformity explained more variance in market mavenism than did demographics. Theoretically, these findings enrich our knowledge of the psychology of market mavens by suggesting some motivations for their behavior. Practically, marketing strategies can be fine‐tuned to appeal more effectively to this important segment of consumers by appealing to mavens' willingness to try new things, to their need for uniqueness, and to their willingness to seek social status through consumption.
Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
997.
Previous studies have reported that, in contrast to the effect on immediate serial recall, lexical/semantic factors have little effect on immediate serial recognition. This has been taken as evidence that linguistic knowledge contributes to verbal short-term memory in a redintegrative process at recall. Contrary to this view, we found that lexicality, frequency, and imageability all influenced matching span. The standard matching span task, requiring changes in item order to be detected, was less susceptible to lexical/semantic factors than was a novel task involving the detection of phoneme order and hence item identity changes. Therefore, in both immediate recognition and immediate serial recall, lexical/semantic knowledge makes a greater contribution to item identity than to item order memory. Task sensitivity, and not the absence of overt recall, may have underpinned previous failures to show effects of these variables in immediate recognition. We also compared matching span for pure and unpredictable mixed lists of words and nonwords. Lexicality had a larger impact on immediate recognition for pure than for mixed lists, in line with findings for immediate serial recall. List composition affected the detection of phoneme but not item order changes in matching span; similarly, in recall, mixed lists produce more frequent word phoneme migrations but not migrations of entire items. These results point to strong similarities between immediate serial recall and recognition. Lexical/semantic knowledge may contribute to phonological stability in both tasks.  相似文献   
998.
This study investigated the maternal concerns and emotions that may regulate one form of sensitive parenting, support for children's immediate desires or intentions. While reviewing a videotape of interactions with their 1-year-olds, mothers who varied on depressive symptoms reported concerns and emotions they had during the interaction. Emotions reflected outcomes either to children (child-oriented concerns) or to mothers themselves (parent-oriented concerns). Child-oriented concerns were associated with fewer negative emotions and more supportive behavior. Supportive parenting was high among mothers who experienced high joy and worry and low anger, sadness, and guilt. However, relations depended on whether emotions were child or parent oriented: Supportive behavior occurred more when emotions were child oriented. In addition, as depressive symptoms increased, mothers reported fewer child-oriented concerns, fewer child-oriented positive emotions, and more parent-oriented negative emotions. They also displayed less supportive behavior. Findings suggest that support for children's immediate intentions may be regulated by parents' concerns, immediate emotions, and depressive symptoms.  相似文献   
999.
There are pragmatic benefits to trait-consistent mood states, especially when people are evaluating new objects within the environment (M. Tamir, M. D. Robinson, & G. L. Clore, 2002). The present studies, involving both naturally occurring (Studies 1 and 2) and manipulated (Study 3) mood states, demonstrated such trait-consistent interactions within the context of neuroticism and negative mood states. Individuals high in neuroticism were faster to make evaluations when in a negative mood state like sadness. By contrast, individuals low in neuroticism were faster to make evaluations when in a neutral mood state. The present studies demonstrate that although negative mood states are hedonically unpleasant, they can be beneficial in some ways for individuals high in neuroticism.  相似文献   
1000.
Three studies involving 478 undergraduates examined the perceived importance of observable actions versus mental states in revealing the "true self"-the authentic and fundamental nature of a target person. Results suggest that when people have only limited information about a target, they believe that an action is more diagnostic of the individual's true self than the accompanying mental state. When participants have knowledge concerning chronic dispositional tendencies of the target, however, they judge that a chronic mental state is more diagnostic of the true self than a chronic action tendency. Considered together, the findings suggest that people conceptualize the true self as a relatively private entity but nevertheless believe that an action of a little-known person may be particularly informative about that individual. Perceived diagnosticity of the true self was partially mediated by inferences concerning the relative stability of actions versus states but not by inferences of volition.  相似文献   
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