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821.
Fran?ois Vachon Sébastien Tremblay 《Revue canadienne de psychologie expérimentale》2005,59(4):279-286
When two target items (T1 and T2) are presented in rapid succession among fillers, processing T2 is often impaired. This phenomenon is known as the attentional blink (AB). Within the visual modality, this second-target deficit generally occurs only if T2 is masked by a trailing item. The current study was designed to examine whether masking of T2 also plays a critical role in the auditory AB. Results showed a reliable AB effect even when the item following T2 was replaced by silence. However, the AB deficit was abolished when T2 was the last presented stimulus. Our results suggest that, as in vision, T2 masking is necessary for the AB to take place in audition, but that masking is effective even when delayed, providing evidence that the phenomenon shares some functional mechanisms across sensory modalities. 相似文献
822.
Michael W Ross Sven-Axel M?nsson Kristian Daneback Ronny Tikkanen 《Cyberpsychology & behavior》2005,8(2):131-139
We compared men who have sex with other men on the Internet with the remainder of the sample of men who reported only sex with women on the Internet, in a sample of 1,846 Swedish men recruited from a major Swedish portal. We report on the self-identified heterosexual men in the sample who reported engaging in cybersex in the past year, and for whom there was complete data on sexual identity and the gender of cybersexual partners. Of the 244 cases with full data, 76% were heterosexual in both identity and behavior, 16% were gay or bisexual in identity and reported both male and female cybersexual contacts on the Internet, and 8% indicated their sexual preference was heterosexual but also reported at least one male sexual partner on the Internet. Thus, 11% of self-identified heterosexual men had sex with other men online. Comparing the two groups, the men who had sex with men (MSM) who did not identify (MSM-NI) spent significantly more time per week online, although a similar amount of time on sexual pursuits, as the heterosexual men. The MSM-NI were significantly more likely to agree that their online sexuality had affected their sexuality in a positive way, to have bought sex from prostitutes, to agree that they do things online that they would not do offline, have cybersex more often, use a web-camera and microphone more often, flirt and visit contact sites more often, and agree more often that sexual thoughts and behaviors are causing problems, desire to have sex creates problems, and sometimes fail to meet commitments due to their sexual behavior. These data taken together suggest that MSM-NI online are not uncommon and are characterized by the extent of their cybersexual involvement that sometimes extends to other men. Such men may rationalize this cybersex with other men as not, or minimally, sexual in much the same way as Humphreys characterized MSMs in public restrooms. 相似文献
823.
Uskali M?ki 《Erkenntnis》2005,63(2):231-251
In order to examine the fit between realism and science, one needs to address two issues: the unit of science question (realism
about which parts of science?) and the contents of realism question (which realism about science?). Answering these questions
is a matter of conceptual and empirical inquiry by way local case studies. Instead of the more ordinary abstract and global
scientific realism, what we get is a doubly local scientific realism based on a bottom-up strategy. Representative formulations
of the former kind are in terms of the truth and reality of the posits of current science, in terms of warranted belief, in
terms of mind-independent unobservable entities. Using illustrations mainly from the social sciences, doubly local scientific
realism denies the global applicability of such formulations and seeks to make adjustments in their elements in response to
information about local units of science: It is sufficient for a realist to give the existence of an entity (and the truth
of a theory) a chance, while in some areas we may be in s position to make justified claims about actual existence (and truth).
Logical inquiry-independent existence is sufficient for the social and human sciences, while mind-independence will be fine
for many other domains. It should not be insisted that the theoretical posits of realist science be strict unobservables in
all areas: most theoretical posits of the social sciences are idealized commonsensibles, such as elements in folk psychology.
Unsurprisingly, this sort of local strategy will create space for realism that is able to accommodate larger areas of science
without sacrificing traditional realist intuitions. 相似文献
824.
Peter?Zachar Kenneth?S?KendlerEmail author 《Philosophy, ethics, and humanities in medicine : PEHM》2012,7(1):4
We compare astronomers' removal of Pluto from the listing of planets and psychiatrists' removal of homosexuality from the
listing of mental disorders. Although the political maneuverings that emerged in both controversies are less than scientifically
ideal, we argue that competition for "scientific authority" among competing groups is a normal part of scientific progress.
In both cases, a complicated relationship between abstract constructs and evidence made the classification problem thorny. 相似文献
825.
ABSTRACT: This commentary examines the incursion on the neutrality of medical personnel now taking place as part of the human rights crises in Bahrain and Syria, and the ethical dilemmas which these incursions place not only in front of physicians practicing in those nations, but in front of the international community as a whole.In Bahrain, physicians have recently received harsh prison terms, apparently for treating demonstrators who clashed with government forces. In Syria, physicians are under the same political pressure to avoid treating political demonstrators or to act as informants against their own patients, turning them in to government authorities. This pressure has been severe, to the point that some physicians have become complicit in the abuse of patients who were also political demonstrators.This paper posits that physicians in certain countries in the Middle East during the "Arab Spring," specifically Syria and Bahrain, are being used as both political pawns and political weapons in clear violation of Geneva Convention and World Medical Association guidelines, and that this puts them into the most extreme sort of "dual loyalty" dilemma. They are being forced to choose between their own safety and well-being and that of their patients -- a negative sum scenario wherein there is no optimal choice. As such, an international call for a United Nations inquiry must be made in order to protect the neutrality of medical care and personnel during times of armed conflict. 相似文献
826.
The death penalty by lethal injection is a legal punishment in the United States. Sodium Thiopental, once used in the death penalty cocktail, is no longer available for use in the United States as a consequence of this association. Anesthesiologists possess knowledge of Sodium Thiopental and possible chemical alternatives. Further, lethal injection has the look and feel of a medical act thereby encouraging physician participation and comment. Concern has been raised that the death penalty by lethal injection, is cruel. Physicians are ethically directed to prevent cruelty within the doctor-patient relationship and ethically prohibited from participation in any component of the death penalty. The US Supreme Court ruled that the death penalty is not cruel per se and is not in conflict with the 8th amendment of the US constitution. If the death penalty is not cruel, it requires no further refinement. If, on the other hand, the death penalty is in fact cruel, physicians have no mandate outside of the doctor patient relationship to reduce cruelty. Any intervention in the name of cruelty reduction, in the setting of lethal injection, does not lead to a more humane form of punishment. If physicians contend that the death penalty can be botched, they wrongly direct that it can be improved. The death penalty cocktail, as a method to reduce suffering during execution, is an unverifiable claim. At best, anesthetics produce an outward appearance of calmness only and do not address suffering as a consequence of the anticipation of death on the part of the condemned. 相似文献
827.
The concept of the management of sexual offenders at risk for recidivism in Northrhine-Wesfalia (Konzeption zumUmgang mitrückfallgef?hrdetenSexualstraft?tern in Nordrhein-Westfalen, KURS NRW) came into effect on February 1, 2010 with a joint circular of the Ministries of Justice, Health and the Interior. Thereby Northrhine-Westfalia has created a systematic for monitoring sexual offenders at risk for recidivism, comparable to those already or in the meantime developed in other federal states in Germany. This article initially describes the procedural nature underlying the KURS concept, regarding mutual information routing and collaboration between the parties involved, i.e. justice, hospital order treatment, police and if necessary others as well. In addition, the framework in which KURS is ingrained, will be shown. Based on case reports this article will finally explain how actions and reactions will be specified in case conferences. Within the systematic KURS it is important that all participants reach all relevant information expeditiously, thus being able to react within their own jurisdiction. When planning actions it is essential to carefully consider the individual case parameters. Within the case conferences it remains a strength of the KURS concept that different perspectives of the case and the offender are bundled together. Ideally this and the case-specific actions will help to avoid similar offences to those committed previously. 相似文献
828.
829.
Neurocognitive studies have shown that extensive musical training enhances P3a and P3b event-related potentials for infrequent target sounds, which reflects stronger attention switching and stimulus evaluation in musicians than in nonmusicians. However, it is unknown whether the short-term plasticity of P3a and P3b responses is also enhanced in musicians. We compared the short-term plasticity of P3a and P3b responses to infrequent target sounds in musicians and nonmusicians during auditory perceptual learning tasks. Target sounds, deviating in location, pitch, and duration with three difficulty levels, were interspersed among frequently presented standard sounds in an oddball paradigm. We found that during passive exposure to sounds, musicians had habituation of the P3a, while nonmusicians showed enhancement of the P3a between blocks. Between active tasks, P3b amplitudes for duration deviants were reduced (habituated) in musicians only, and showed a more posterior scalp topography for habituation when compared to P3bs of nonmusicians. In both groups, the P3a and P3b latencies were shortened for deviating sounds. Also, musicians were better than nonmusicians at discriminating target deviants. Regardless of musical training, better discrimination was associated with higher working memory capacity. We concluded that music training enhances short-term P3a/P3b plasticity, indicating training-induced changes in attentional skills. 相似文献
830.
Laura P. McAvinue Thomas Habekost Katherine A. Johnson S?ren Kyllingsb?k Signe Vangkilde Claus Bundesen Ian H. Robertson 《Attention, perception & psychophysics》2012,74(8):1570-1582
Changes in sustained attention, attentional selectivity, and attentional capacity were examined in a sample of 113 participants between the ages of 12 and 75. To measure sustained attention, we employed the sustained-attention-to-response task (Robertson, Manly, Andrade, Baddeley, & Yiend, Neuropsychologia 35:747?C58, 1997), a short continuous-performance test designed to capture fluctuations in sustained attention. To measure attentional selectivity and capacity, we employed a paradigm based on the theory of visual attention (Bundesen, Psychological Review 97:523?C547, 1990), which enabled the estimation of parameters related to attentional selection, perceptual threshold, visual short-term memory capacity, and processing capacity. We found evidence of age-related decline in each of the measured variables, but the declines varied markedly in terms of magnitude and lifespan trajectory. Variables relating to attentional capacity showed declines of very large effect sizes, while variables relating to attentional selectivity and sustained attention showed declines of medium to large effect sizes, suggesting that attentional control is relatively preserved in older adults. The variables relating to sustained attention followed a U-shaped, curvilinear trend, and the variables relating to attentional selectivity and capacity showed linear decline from early adulthood, providing further support for the differentiation of attentional functions. 相似文献