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941.
This article explores the ethical concept of neutrality through use of a psychiatric clinical vignette. In this case a psychiatry resident is faced with the treatment of a patient who was found by the FBI to be in possession of child pornography. Although not accused of any other crimes, the patient was a fugitive from the law and requesting treatment for pedophilia. Faced with the pressures of limited resources and anxiety about the patient's dangerousness to others, the resident and his supervisor tried to strike a balance between the ethical principles of neutrality and beneficence. Through this vignette, the importance of neutrality, as well as how it can be compromised by other pressures such as expediency and anxiety, is explored. 相似文献
942.
Ninness C Rumph R McCuller G Harrison C Ford AM Ninness SK 《Journal of applied behavior analysis》2005,38(1):1-22
Following a pretest, 11 participants who were naive with regard to various algebraic and trigonometric transformations received an introductory lecture regarding the fundamentals of the rectangular coordinate system. Following the lecture, they took part in a computer-interactive matching-to-sample procedure in which they received training on particular formula-to-formula and formula-to-graph relations as these formulas pertain to reflections and vertical and horizontal shifts. In training A-B, standard formulas served as samples and factored formulas served as comparisons. In training B-C, factored formulas served as samples and graphs served as comparisons. Subsequently, the program assessed for mutually entailed B-A and C-B relations as well as combinatorially entailed C-A and A-C relations. After all participants demonstrated mutual entailment and combinatorial entailment, we employed a test of novel relations to assess 40 different and complex variations of the original training formulas and their respective graphs. Six of 10 participants who completed training demonstrated perfect or near-perfect performance in identifying novel formula-to-graph relations. Three of the 4 participants who made more than three incorrect responses during the assessment of novel relations showed some commonality among their error patterns. Derived transfer of stimulus control using mathematical relations is discussed. 相似文献
943.
Does memory retrieval occur in a continuous or an all-or-none manner? The shape of the receiver operating characteristic (ROC) has been used to answer this question, with curvilinear and linear memory ROCs indicating continuous and all-or-none retrieval processes, respectively. Signal detection models (e.g., the unequal variance model) correspond to a continuous retrieval process, whereas threshold models (including the multinomial model and the recollection component of the dual-process model) correspond to an all-or-none process. In studies of source memory, Slotnick et al. (2000) and others have observed curvilinear ROCs (supporting the unequal variance model), whereas Yonelinas (1999) observed linear ROCs (supporting the dual-process model). We resolve these seemingly inconsistent results, showing that source memory ROCs are naturally curvilinear but can appear linear when nondiagnostic source information is included in the analysis. Furthermore, the unequal variance model accounted for both recognition memory and source memory ROCs, supporting a continuous process of memory retrieval. 相似文献
944.
Gretchen?J.?DiefenbachEmail author David?F.?Tolin Johanna?Crocetto Nicholas?Maltby Scott?Hannan 《Journal of psychopathology and behavioral assessment》2005,27(3):169-178
Currently there is no gold standard treatment outcome measure for trichotillomania (TTM), a disorder characterized by repetitive hair pulling resulting in noticeable hair loss. The goal of the current study was to evaluate the psychometric properties of TTM measures of differing assessment methods: self-report, clinician-rated summary scales, and clinician-rated global severity scales. Data collected from 28 patients with TTM indicated mixed psychometric properties for current scales. Internal consistency was strong for self-report but not clinician-rated summary scales. One clinician-rated summary scale total and subjective ratings of hair loss demonstrated good interrater agreement. Although convergent validity was good within measurement type, self-report did not correlate with clinician-rated global severity scales, perhaps because of absence of hair loss severity assessment on the self-report measure. A multimethod assessment including one of each type of measure reviewed in this paper, along with self-monitoring and measures of hair loss severity, is recommended for a comprehensive best practice approach to TTM assessment. 相似文献
945.
Levine C 《Kennedy Institute of Ethics journal》2005,15(4):371-383
Advances in medical technology now permit children who need ventilator assistance to live at home rather than in hospitals or institutions. What does this ventilator-dependent life mean to children and their families? The impetus for this essay comes from a study of the moral experience of 12 Canadian families--parents, ventilator-dependent child, and well siblings. These families express great love for their children, take on enormous responsibilities for care, live with uncertainty, and attempt to create "normal" home environments. Nevertheless, they experience social isolation, sometimes even from their extended families and health care providers. Their lives are constrained in many ways. The challenges faced by parents of technology-dependent children raise questions of justice within society and within families. 相似文献
946.
Irwin SA Christmon CA Grossman AW Galvez R Kim SH DeGrush BJ Weiler IJ Greenough WT 《Neurobiology of learning and memory》2005,83(3):180-187
Fragile X mental retardation protein (FMRP), which is absent in fragile X syndrome, is synthesized in vitro in response to neurotransmitter activation. Humans and mice lacking FMRP exhibit abnormal dendritic spine development, suggesting that this protein plays an important role in synaptic plasticity. Previously, our laboratory demonstrated increased FMRP immunoreactivity in visual cortex of rats exposed to complex environments (EC) and in motor cortex of rats trained on motor-skill tasks compared with animals reared individually in standard laboratory housing (IC). Here, we use immunohistochemistry to extend those findings by investigating FMRP levels in visual cortex and hippocampal dentate gyrus of animals exposed to EC or IC. Rats exposed to EC for 20 days exhibited increased FMRP immunoreactivity in visual cortex compared with animals housed in standard laboratory caging. In the dentate gyrus, animals exposed to EC for 20 days had higher FMRP levels than animals exposed to EC for 5 or 10 days. In light of possible antibody crossreactivity with closely related proteins FXR1P and FXR2P, FMRP immunoreactivity in the posterior-dorsal one-third of cerebral cortex was also examined by Western blotting following 20 days of EC exposure. FMRP levels were greater in EC animals, whereas levels of FXR1P and FXR2P were unaffected by experience. These results provide further evidence for behaviorally induced alteration of FMRP expression in contrast to its homologues, extend previous findings suggesting regulation of its expression by synaptic activity, and support the theories associating FMRP expression with alteration of synaptic structure both in development and later in the life-cycle. 相似文献
947.
Publication bias, sometimes known as the "file-drawer problem" or "funnel-plot asymmetry," is common in empirical research. The authors review the implications of publication bias for quantitative research synthesis (meta-analysis) and describe existing techniques for detecting and correcting it. A new approach is proposed that is suitable for application to meta-analytic data sets that are too small for the application of existing methods. The model estimates parameters relevant to fixed-effects, mixed-effects or random-effects meta-analysis contingent on a hypothetical pattern of bias that is fixed independently of the data. The authors illustrate this approach for sensitivity analysis using 3 data sets adapted from a commonly cited reference work on research synthesis (H. M. Cooper & L. V. Hedges, 1994). 相似文献
948.
Little is known about whether infants perceive meter, the underlying temporal structure of music. We employed a habituation paradigm to examine whether 7-month-old infants could categorize rhythmic and melodic patterns on the basis of the underlying meter, which was implied from event and accent frequency of occurrence. In Experiment 1, infants discriminated duple and triple classes of rhythm on the basis of implied meter. Experiment 2 replicated this result while controlling for rhythmic grouping structure, confirming that infants perceived metrical structure despite occasional ambiguities and conflicting group structure. In Experiment 3, infants categorized melodies on the basis of contingencies between metrical position and pitch. Infants presented with metrical melodies detected reversals of pitch/meter contingencies, while infants presented with non-metrical melodies showed no preference. Results indicate that infants can infer meter from rhythmic patterns, and that they may use this metrical structure to bootstrap their knowledge acquisition in music learning. 相似文献
949.
Clinical interviews administered to third- to sixth-graders explored children's conceptualizations of rational number and of certain extensive physical quantities. We found within child consistency in reasoning about diverse aspects of rational number. Children's spontaneous acknowledgement of the existence of numbers between 0 and 1 was strongly related to their induction that numbers are infinitely divisible in the sense that they can be repeatedly divided without ever getting to zero. Their conceptualizing number as infinitely divisible was strongly related to their having a model of fraction notation based on division and to their successful judgment of the relative magnitudes of fractions and decimals. In addition, their understanding number as infinitely divisible was strongly related to their understanding physical quantities as infinitely divisible. These results support a conceptual change account of knowledge acquisition, involving two-way mappings between the domains of number and physical quantity. 相似文献
950.
We addressed the hypothesis that word segmentation based on statistical regularities occurs without the need of attention. Participants were presented with a stream of artificial speech in which the only cue to extract the words was the presence of statistical regularities between syllables. Half of the participants were asked to passively listen to the speech stream, while the other half were asked to perform a concurrent task. In Experiment 1, the concurrent task was performed on a separate auditory stream (noises), in Experiment 2 it was performed on a visual stream (pictures), and in Experiment 3 it was performed on pitch changes in the speech stream itself. Invariably, passive listening to the speech stream led to successful word extraction (as measured by a recognition test presented after the exposure phase), whereas diverted attention led to a dramatic impairment in word segmentation performance. These findings demonstrate that when attentional resources are depleted, word segmentation based on statistical regularities is seriously compromised. 相似文献