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971.
Behavior-reduction interventions typically employ dense schedules of alternative reinforcement in conjunction with operant extinction for problem behavior. After problem behavior is reduced in the initial treatment stages, schedule thinning is routinely conducted to make the intervention more practical in natural environments. In the current investigation, two methods for thinning alternative reinforcement schedules were compared for 3 clients who exhibited severe problem behavior. In the dense-to-lean (DTL) condition, reinforcement was delivered on relatively dense schedules (using noncontingent reinforcement for 1 participant and functional communication training for 2 participants), followed by systematic schedule thinning to progressively leaner schedules. During the fixed lean (FL) condition, reinforcement was delivered on lean schedules (equivalent to the terminal schedule of the DTL condition). The FL condition produced a quicker attainment of individual treatment goals for 2 of the 3 participants. The results are discussed in terms of the potential utility of using relatively lean schedules at treatment outset.  相似文献   
972.
This research examined the relative contributions of two aspects of executive function-inhibitory control and planning ability-to theory of mind in 49 3- and 4-year-olds. Children were given two standard theory of mind measures (Appearance-Reality and False Belief), three inhibitory control tasks (Bear/Dragon, Whisper, and Gift Delay), three planning tasks (Tower of Hanoi, Truck Loading, and Kitten Delivery), and a receptive vocabulary test (Peabody Picture Vocabulary Test [PPVT-3]). Multiple regression analyses indicated that two inhibition tasks (Bear/Dragon and Whisper) were significantly related to theory of mind after accounting for age, receptive vocabulary, and planning. In contrast, the planning tasks did not share unique variance with theory of mind. These results increase our understanding of the specific nature of executive function-theory of mind relations during early childhood.  相似文献   
973.
This article reports the first findings of the Würzburg Longitudinal Memory Study, which focuses on children's verbal memory development, particularly the acquisition of memory strategies. At the beginning of the study, 100 kindergarten children (mean age 6 1/2 years) were tested on various memory measures, including sort-recall, text recall, short-term memory capacity, and metamemory. Assessments were repeated twice, with adjacent measurement points separated by 6-month time intervals. One major goal of the initial phase of the study concerned the exploration of the utilization deficiency phenomenon, which refers to the fact that young children who spontaneously use a memory strategy for the first time do not experience immediate memory benefits. Results obtained for the sort-recall task showed that, among those children who acquired a sorting strategy between Times 1 and 2, only a small proportion experienced the utilization deficiency problem. Additional analyses demonstrated that these few children also performed more poorly on the short-term memory tasks and the text recall measure when compared with the groups of efficient strategy users, suggesting that utilization deficiency is accompanied by a more general memory capacity problem. Overall, the findings revealed enormous variability in the early acquisition of memory strategies, indicating that the utilization deficiency phenomenon might not be as frequent as is assumed in the relevant literature.  相似文献   
974.
This study examined the equivalence of the Child Behavior Checklist/1 1/2-5 (CBCL/1 1/2-5) in 682 parents of 2- to 4-year-old children stratified by parent race/ethnicity (African American, Latino, and non-Latino White), family income (low vs. middle-upper), and language version (Spanish vs. English). Externalizing Scale means differed by income and child gender. Internalizing Scale means differed by income and parent race/ethnicity. Differential item analyses showed that few items functioned differently by racial/ethnic, language, and income group. A confirmatory factor analysis demonstrated that the Externalizing Scale provided a good fit with the data across racial/ethnic and income groups. However, model fit was improved for the Internalizing Scale when factor weights were allowed to vary. Findings support the equivalence of the CBCL/1 1/2-5 when used with parents of low-income preschool children from African American and Latino backgrounds, although further study of the factor structure for the Internalizing Scale is recommended.  相似文献   
975.
This article presents and discusses four clinical cases that exemplify the complexity of ethical dilemmas concerning the provider's obligation to disclose or withhold genetic information from patients. Case 1: What is the responsibility of the cancer genetics provider to ensure that a positive test results is shared with distant relatives? Case 2: To ensure that results go to at-risk relatives, do we have the right to ignore the wishes of the designated next-of-kin? Case 3: Do we have the right to reveal a familial BRCA1 mutation to a patient's relative, who is at 50% risk? Case 4: Do we have an obligation to reveal that a patient is not a blood relative and therefore, not at risk to have inherited a familial mutation? These cases form the basis for discussing the provider's dual obligations to keeping patient confidentiality and informing patients and families about risk (i.e. duty to warn). We also provide a summary of consensus points and additional discussion questions for each case.  相似文献   
976.
Explicitly cued task switching with multiple cues per task permits three types of transitions: cue repetitions (cue and task repeat), task repetitions (cue changes but task repeats), and task alternations (cue and task change). The difference between task alternations and task repetitions can be interpreted as a switch cost, but its magnitude varies substantially across experiments. We investigated how switch cost is affected by transition frequency (how often subjects repeat and switch tasks) with an experiment in which each transition had a frequency of .70 in separate sessions. Switch cost was smallest when task alternations were frequent and largest when task repetitions were frequent. Mathematical modeling of the data indicated that the different “switch costs” reflected priming of cue encoding for frequent transitions. Interpretations of our findings based on automatic priming from memory retrieval of past transitions and strategic priming from transition expectancies are discussed.  相似文献   
977.
978.
The similarity of documents in a large database of published Fractals articles was examined for redundancy. Three different text matching techniques were used on published Abstracts to identify redundancy candidates, and predictions were verified by reading full text versions of the redundancy candidate articles. A small fraction of the total articles in the database was judged to be redundant. This was viewed as a lower limit, because it excluded cases where the concepts remained the same, but the text was altered substantially. Far more pervasive than redundant publications were publications that did not violate the letter of redundancy but rather violated the spirit of redundancy. There appeared to be widespread publication maximization strategies. Studies that resulted in one comprehensive paper decades ago now result in multiple papers that focus on one major problem, but are differentiated by parameter ranges, or other stratifying variables. This ‘paper inflation’ is due in large part to the increasing use of metrics (publications, patents, citations, etc) to evaluate research performance, and the researchers’ motivation to maximize the metrics. The views in this paper are solely those of the authors, and do not necessarily represent the views of the Department of the Navy or any of its components, UNAM, University of Virginia or University of Karlsruhe.  相似文献   
979.
Laboratory based training studies suggest that older adults can benefit from training in tasks that tap control aspects of attention. This was further explored in the present study in which older and younger adults completed an adaptive and individualized dual-task training program. The testing-the-limits approach was used [Lindenberger, U., & Baltes, P. B. (1995). Testing-the-limits and experimental simulation: Two methods to explicate the role of learning in development. Human Development, 38, 349-360.] in order to gain insight into how attentional control can be improved in older adults. Results indicated substantial improvement in overlapping task performance in both younger and older participants suggesting the availability of cognitive plasticity in both age groups. Improvement was equivalent among age groups in response speed and performance variability but larger in response accuracy for older adults. The results suggest that time-sharing skills can be substantially improved in older adults.  相似文献   
980.
In recognition memory tasks, emotionally negative words are judged more often as "old" relative to emotionally neutral words, suggesting a shift in response bias. We wondered whether this bias shift was due to the flexible regulation of executive control during memory retrieval. To address this question, we investigated individuals with high variability in executive control functions. As expected, we observed that emotional word meaning did indeed have a strong influence on the bias toward responding "old," independent of recognition accuracy and overall response bias. However, these effects were uncorrelated with executive control, as measured by the Trail Making Test, and were fully intact, even in a sample of hospitalized neurological patients with severe executive dysfunctions, some of whom had marked damage in fronto-thalamo-striatal networks. Having concluded that the emotion-induced bias must develop on different grounds, we went on to discuss alternative explanations.  相似文献   
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