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131.
Successful treatment of many childhood diseases once considered terminal has resulted in the emergence of long-term effects of the disease or consequences of treatment that were previously unrecognized. Many of these long-term effects involve the central nervous system (CNS) and are developmental in the way that they emerge over time. Because we are now able to observe the natural history of childhood diseases such as sickle cell anemia or HIV, or the consequences of treatment of disease such as leukemia, brain tumors, or kidney disease, we are also able to study a number of biological mechanisms that result in long-term neurocognitive impairment. While some of the neurodevelopmental outcomes can be directly linked to structural damage of the CNS, other systems (e.g., hematologic, immunologic, pulmonary) appear to play crucial indirect roles in the development of the CNS and neurocognitive abilities because of the way that they affect the course of brain development and activity of the brain across time. Important interactions between acute disease factors, biological mechanisms, age at the time of disease or treatment effect, and disruptions in patterns of development after successful treatment or management all provide support for a neurodevelopmental model of childhood chronic illness. Testing this model may make it possible to more accurately predict the timing and degree of severity of long-term neurodevelopmental consequences, provide guidance for improved treatment and prevention, and offer better understanding of neurodevelopmental disruptions that occur in other non-chronic illness related disabilities.  相似文献   
132.
Searching for icons, symbols, or signs is an integral part of tasks involving computer or radar displays, head-up displays in aircraft, or attending to road traffic signs. Icons therefore need to be designed to optimize search times, taking into account the factors likely to slow down visual search. Three factors likely to adversely affect visual search were examined: the time of day at which search was carried out, the visual complexity of the icons, and the extent to which information features in the icon were grouped together. The speed with which participants searched icon arrays for a target was slower early in the afternoon, when icons were visually complex and when information features in icons were not grouped together to form a single object. Theories of attention that account for both feature-based and object-based search best explain these findings and are used to form the basis for ways of improving icon design.  相似文献   
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Natural scenes contain far more information than can be processed simultaneously. Thus, our visually guided behavior depends crucially on the capacity to attend to relevant stimuli. Past studies have provided compelling evidence of functional overlap of the neural mechanisms that control spatial attention and saccadic eye movements. Recent neurophysiological work demonstrates that the neural circuits involved in the preparation of saccades also play a causal role in directing covert spatial attention. At the same time, other studies have identified separable neural populations that contribute uniquely to visual and oculomotor selection. Taken together, all of the recent work suggests how visual and oculomotor signals are integrated to simultaneously select the visual attributes of targets and the saccades needed to fixate them.  相似文献   
135.
520 college students from a public university in the southwest were questioned to examine correlations between having a tattoo and the presence of tattoos among their family and friends. Tattoos among both friends and family were positively correlated with respondents' having a tattoo. The magnitude of friends' influence was about double the influence of family.  相似文献   
136.
In recent studies, researchers have examined animals' use of absolute or relational distances in finding a hidden goal. When trained with an array of landmarks, most animals use the default strategy of searching at an absolute distance from 1 or more landmarks. In contrast, when trained in enclosures, animals often use the relationship among walls. In the present study, pigeons were trained to find the center of an array of landmarks or a set of short walls that did not block external cues. Expansion tests showed that both groups of pigeons primarily used an absolute distance strategy. However, on rotational tests, pigeons continued to search in the center of the array, suggesting that direction was learned in relation to array.  相似文献   
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138.
Childhood obesity, which is due in part to lack of physical activity, is a serious concern that requires the attention of the behavioral community. Although excessive video game play has been noted in the literature as a contributor to childhood obesity, newer video gaming technology, called exergaming, has been designed to capitalize on the reinforcing effects of video games to increase physical activity in children. This study evaluated the effects of exergaming on physical activity among 4 inactive children in a physical education (PE) classroom. Results showed that exergaming produced substantially more minutes of physical activity and more minutes of opportunity to engage in physical activity than did the standard PE program. In addition, exergaming was socially acceptable to both the students and the PE teacher. Exergaming appears to hold promise as a method for increasing physical activity among inactive children and might be a possible intervention for childhood obesity.  相似文献   
139.
Transference occurs when a perceiver's representation of a significant other is activated and applied to a new target person (Andersen & Chen, 2002). Extending past research, it was hypothesized that transference occurs even when a target person possesses a core feature—namely, group membership status—that is inapplicable to the relevant significant-other representation. Supporting this, transference led perceivers to make representation-consistent memory and evaluation judgments about a target—regardless of whether the target's political (experiment 1) or ethnic (experiment 2) group membership was the same or different from that of the relevant significant other. Moreover, in experiment 2, perceivers undergoing transference involving a positively evaluated significant other behaved more positively toward the target even when the target was from an ethnic out-group. The results represent initial evidence of transference processes occurring across group boundaries. Implications for transference and the reduction of out-group bias are discussed.  相似文献   
140.
Previous accounts of the memory distortion known as the change-of-standard effect hypothesize that participants form a relative impression of a target at encoding and later use that impression with the average of all items to recall the target (Higgins & Lurie, 1983). In three experiments, we investigated the standard and the integration of the standard with the relative impression. Experiments 1 and 2 show that participants’ subjective average at recall is distorted toward recent stimuli: It is computed when required and is therefore affected by the items’ accessibility at that time. Furthermore, the impression’s influence on recall is relatively small when the context changes between encoding and decoding. Experiment 3 shows that this change in the impression’s influence occurs only when the participant integrates information across sessions, suggesting that such tasks make participants aware of the changed context and cause them to adjust the use of their impression in recalling the target.  相似文献   
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