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231.
Three experiments were conducted to investigate the impact of stimulus-driven control on the time-course of stimulus-response (SR) compatibility. Participants responded to the presence or absence of a singleton arrow that was presented among multiple nontargets. When the singleton arrow was present, observers pressed a button with their right index finger, when it was absent they pressed with their left-index finger. SR-compatibility depended on the relation between the identity of the target and the present response: Even though the identity of the target singleton arrow (whether it was pointing to the right or left) was irrelevant to the task, the direction could be corresponding (right arrow) or noncorresponding (left arrow) with a target present response (the right hand). To examine the time-course of performance target-distractor similarity was varied to increase or decrease visual search efficiency and accordingly response latency. There were three main findings. First, the results of Experiment 1 showed that observers were no faster to respond 'present' when the singleton arrow pointed to the right (corresponding to the right hand) than when it pointed left (noncorresponding to the right hand) in a simple present-absent detection task. Second, only when observers were encouraged to process the identity of the arrow singleton, an effect of an SR-compatibility effect was found which developed over time. Third, the time-course of SR-compatibility was not influenced by visual search efficiency. The results of the present work suggest that visual selection and response selection occur in different stages. 相似文献
232.
Jotkowitz A 《Journal of religion and health》2011,50(4):835-840
A new bill regulating ovum donation in Israel is set to pass its second and third readings in the Israel Parliament in the
upcoming months. The new law will expand the number of locally donated ova available, as previously Israeli women were prohibited
from donating eggs unless they were undergoing fertility treatment. Parallel to this legislative initiative, there has been
a change in rabbinical thinking over who is considered the mother in a case of surrogacy. Previously, the consensus has been
that the birth mother is to be considered the mother, but over the last few years there has been a change in thinking and
the genetic mother is now considered the mother. The purpose of this paper is to present the ethical and legal issues from
a Jewish perspective in determining maternal identity. The dilemma also demonstrates some of the difficulties in applying
Talmudic law to modern problems and the various methodologies used to overcome these issues. 相似文献
233.
234.
Genuine moral disagreement exists and is widespread. To understand such disagreement, we must examine the basic kinds of social relationships people construct across cultures and the distinct moral obligations and prohibitions these relationships entail. We extend relational models theory (Fiske, 1991) to identify 4 fundamental and distinct moral motives. Unity is the motive to care for and support the integrity of in-groups by avoiding or eliminating threats of contamination and providing aid and protection based on need or empathic compassion. Hierarchy is the motive to respect rank in social groups where superiors are entitled to deference and respect but must also lead, guide, direct, and protect subordinates. Equality is the motive for balanced, in-kind reciprocity, equal treatment, equal say, and equal opportunity. Proportionality is the motive for rewards and punishments to be proportionate to merit, benefits to be calibrated to contributions, and judgments to be based on a utilitarian calculus of costs and benefits. The 4 moral motives are universal, but cultures, ideologies, and individuals differ in where they activate these motives and how they implement them. Unlike existing theories (Haidt, 2007; Hauser, 2006; Turiel, 1983), relationship regulation theory predicts that any action, including violence, unequal treatment, and "impure" acts, may be perceived as morally correct depending on the moral motive employed and how the relevant social relationship is construed. This approach facilitates clearer understanding of moral perspectives we disagree with and provides a template for how to influence moral motives and practices in the world. 相似文献
235.
Caroline H.S. Barwood Bruce E. Murdoch Brooke-Mai Whelan David Lloyd Stephan Riek John D. OSullivan Alan Coulthard Andrew Wong 《Brain and language》2011,116(3):125-135
Low frequency Repetitive Transcranial Magnetic Stimulation (rTMS) has previously been applied to language homologues in non-fluent populations of persons with aphasia yielding significant improvements in behavioral language function up to 43 months post stimulation. The present study aimed to investigate the electrophysiological correlates associated with the application of rTMS through measurement of the semantic based N400 Event-related brain potentials (ERP) component. Low frequency (1 Hz) rTMS was applied to the anterior portion of the homologue to Broca’s area (pars triangularis), for 20 min per day for 10 days, using a stereotactic neuronavigational system. Twelve non-fluent persons with aphasia, 2-6 years post stroke were stimulated. Six participants were randomly assigned to receive real stimulation and six participants were randomly assigned to receive a blind sham control condition. ERP measures were recorded at baseline, 1 week and 2 months subsequent to stimulation. The findings demonstrate treatment related changes observed in the stimulation group when compared to the placebo control group at 2 months post stimulation indicating neuromodulation of N400 as a result of rTMS. No treatment related changes were identified in the stimulation group, when compared to the sham group from baseline to 1 week post stimulation. The electrophysiological results represent the capacity of rTMS to modulate neural language networks and measures of lexical-semantic function in participants with non-fluent aphasia and suggest that time may be an important factor in brain reorganization subsequent to rTMS. 相似文献
236.
Ross D. Henderson Michael Allerhand Niall Patton Alison Pattie Alan J. Gow Baljean Dhillon John M. Starr Ian J. Deary 《Intelligence》2011,39(2-3):148-154
The extent to which visual function, measured as near and distant visual acuity and contrast sensitivity, is correlated with concurrently measured cognitive function and prior intellectual ability was investigated in a narrow age range group known as the Lothian Birth Cohort of 1921 (LBC1921). Participants were aged ~ 83 years at the time of testing (N = 321). A well-fitting structural equation model highlighted a significant contribution of a latent visual trait to a general fluid intelligence factor in old age, independent of the contribution from childhood intelligence. Additionally, childhood intelligence made a significant contribution to the general visual factor in old age. However, the model fitted equally well when the fluid intelligence factor is assumed to be a cause of the visual function latent trait, in which case childhood intelligence does not significantly influence vision in old age. We discuss these results with respect to four possible mechanisms by which vision and cognition can come to be correlated over the lifecourse. 相似文献
237.
Alan Blum 《The Journal of medical humanities》2014,35(1):19-36
If philosophers have discussed life as preparation for death, this seems to make aging coterminous with dying and a melancholy passage that we are condemned to survive. It is important to examine the discourse on aging and end of life and the ways various models either limit possibilities for human agency or suggest means of being innovative in relation to such parameters. I challenge developmental views of aging not by arguing for eternal life, but by using Plato’s conception of form in conjunction with Simmel’s work and Arendt’s meditation on intergenerational solidarity, to evoke a picture of the subject as having capacities that offer avenues for improvisational action. This paper proposes a method for analyzing any social form as a problem-solving situation where the real “problem” is the fundamental ambiguity that inheres in the mix between the finite characteristics of the action and its infinite perplexity. I work through the most conventional chronological view of aging to show how it dramatizes a fundamental ethical collision in life that intensifies anxiety under many conditions, always raising the question of what is to be done with respect to contingency, revealing such “work” as a paradigm of the human condition. 相似文献
238.
Mallory R. Sdano Rena J. Vanzo Megan M. Martin Erin E. Baldwin Sarah T. South Alan F. Rope William P. Allen Hutton Kearney 《Journal of genetic counseling》2014,23(6):922-927
Mosaic chromosomal abnormalities are relatively common. However, mosaicism may be missed due to multiple factors including failure to recognize clinical indications and order appropriate testing, technical limitations of diagnostic assays, or sampling tissue (s) in which mosaicism is either not present, or present at very low levels. Blood leukocytes have long been the “gold standard” sample for cytogenetic analysis; however, the culturing process for routine chromosome analysis can complicate detection of mosaicism since the normal cell line may have a growth advantage in culture, or may not be present in the cells that produce metaphases (the lymphocytes). Buccal cells are becoming increasingly utilized for clinical analyses and are proving to have many advantages. Buccal swabs allow for simple and noninvasive DNA collection. When coupled with a chromosomal microarray that contains single nucleotide polymorphic probes, analysis of buccal cells can maximize a clinician’s opportunity to detect cytogenetic mosaicism. We present three cases of improved diagnosis of mosaic aberrations using buccal specimens for chromosomal microarray analysis. In each case, the aberration was either undetectable in blood or present at such a low level it likely could have gone undetected. These cases highlight the limitations of certain laboratory methodologies for identifying mosaicism. We also present practice implications for genetic counselors, including clinic workflow changes and counseling approaches based on increasing use of buccal samples. 相似文献
239.
Recent research has determined that word meanings can instantly influence the meaning and distribution of other words in the sentence. Here, we manipulated basic carrier sentences with the disjunction or linking two nouns that were either filling the same thematic role or not, and were either semantically related or not. Though previous research has shown that one word can prime a semantically related word even in a sentential context, we predicted that if or cues knowledge about contextually‐relevant alternatives, priming for semantic relatives will only obtain when those words also fill the same thematic role. These predictions were confirmed, as self‐paced reading times of the second alternative in the sentence were faster only when the two alternatives shared the same thematic role and semantic category, suggesting that disjunction words like or function similarly to verbs, which cue knowledge about expected argument structure and sense depending on sentential context. The relevance of these findings for basic reasoning phenomena (i.e., the subadditivity effect) is also discussed. 相似文献
240.
We examine a distinctive kind of problem for decision theory, involving what we call discontinuity at infinity. Roughly, it arises when an infinite sequence of choices, each apparently sanctioned by plausible principles, converges to a ‘limit choice’ whose utility is much lower than the limit approached by the utilities of the choices in the sequence. We give examples of this phenomenon, focusing on Arntzenius et al.’s Satan’s apple, and give a general characterization of it. In these examples, repeated dominance reasoning (a paradigm of rationality) apparently gives rise to a situation closely analogous to having intransitive preferences (a paradigm of irrationality). Indeed, the agents in these examples are vulnerable to a money pump set-up despite having preferences that exhibit no obvious defect of rationality. We explore several putative solutions to such problems, particularly those that appeal to binding and to deliberative dynamics. We consider the prospects for these solutions, concluding that if they fail, the examples show that money pump arguments are invalid. 相似文献