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51.
Wendler D 《Kennedy Institute of Ethics journal》1998,8(3):307-327
The exclusion of potential subjects based on increased risks is a common practice in human subjects research. However, there are no guidelines to ensure that this practice is conducted in a systematic and fair way. This gap in the literature and regulation is addressed by a specific account of a "condition on inclusion risks" (CIR), a condition under which potential subjects should be excluded from research on the basis of increased risks. This account provides a general framework for assessing standard exclusions as well as more controversial ones such as the exclusion of pregnant women and women of childbearing potential from certain types of research. 相似文献
52.
1848年问世的《共产党宣言》,是马克思和恩格斯参加的共产主义者同盟的纲领。毫无疑问,《宣言》是欧洲的,因为它在伦敦印刷,是由两个德国撰稿人完成的,这两个人在布鲁塞尔邂逅而且都加入了主要由德国人组成的、总部设在巴黎(后移至伦敦)的一个组织。可能正是由于警察的镇压,共产主义的幽灵才在欧洲徘徊。面对资本主义的世界化,革命者已经在反对资产阶级国际主义的实践,马克思和恩格斯于1843年夏天在巴黎相遇,而恩格斯曾谈到自这次相遇以来,他们已经有了一个理论的完整协议,他们第二次相遇在1844年春天,于布鲁塞尔,而恩格斯断言说,在那时,马克思“已经完全确立了他的历史唯物主义的学说”。 相似文献
53.
Event-related brain potentials (ERPs) were recorded while participants read and made acceptability judgments about sentences containing three types of adjective sequences: (1) normal sequences--e.g., Jennifer rode a huge gray elephant; (2) reversed sequences that violate grammatical-semantic constraints on linear order--e.g., *Jennifer rode a gray huge elephant; and (3) contradictory sequences that violate lexical-semantic constraints on compositionality--e.g., *Jennifer rode a small huge elephant. Relative to the control condition, the second adjective elicited a reduced N400 and an enhanced P600 in both the reversal condition and the contradiction condition. We present several alternative accounts of these two effects, but favor an interpretation which treats them as reflecting semantic and syntactic aspects of a temporary reanalysis of the adjective order construction. Furthermore, relative to the control condition, the final noun elicited a robust N400 in the contradiction condition but not in the reversal condition. We suggest that this effect indexes the full registration of the lexical-semantic incompatibility of the two adjectives in the contradiction condition. Finally, we discuss how all of these findings fit into the broader context of recent ERP studies that have reported atypical N400s and robust P600s in response to certain types of semantic anomalies. 相似文献
54.
Geraerts E Kozarić-Kovacić D Merckelbach H Peraica T Jelicic M Candel I 《Consciousness and cognition》2007,16(1):170-177
Several authors have argued that traumatic experiences are processed and remembered in a qualitatively different way from neutral events. To investigate this issue, we interviewed 121 Croatian war veterans diagnosed with posttraumatic stress disorder (PTSD) about amnesia, intrusions (i.e., flashbacks and nightmares), and the sensory qualities of their most horrific war memories. Additionally, they completed a self-report scale measuring dissociative experiences. In contrast to what one would expect on the basis of theories emphasizing the special status of traumatic memories, amnesia, and high frequency intrusions were not particularly typical for our sample of traumatized individuals. Moreover, traumatic memories were not qualitatively different from neutral memories with respect to their stability and sensory qualities. The severity of PTSD symptoms was not significantly correlated with dissociative experiences. Our findings do not support the existence of special memory mechanisms that are unique to experiencing traumatic events. 相似文献
55.
Six unsuccessful attempts at replicating a key finding in the linguistic relativity literature [Boroditsky, L. (2001). Does language shape thought?: Mandarin and English speakers' conceptions of time. Cognitive Psychology, 43, 1-22] are reported. In addition to these empirical issues in replicating the original finding, theoretical issues present in the original report are discussed. In sum, we conclude that Boroditsky (2001) provides no support for the Whorfian hypothesis. 相似文献
56.
The processing of words and pictures representing actions and objects was tested in 21 aphasic patients and 20 healthy controls across three word production tasks: picture-naming (PN), single word reading (WR) and word repetition (WRP). Analysis 1 targeted task and lexical category (noun-verb), revealing worse performance on PN and verb items for both patients and control participants. For Analysis 2 we used data collected in a concurrent gesture norming study to re-categorize the noun-verb items along hand imagery parameters (i.e., objects that can/cannot be manipulated and actions which do/do not involve fine hand movements). Here, patients displayed relative difficulty with the 'manipulable' items, while controls displayed the opposite pattern. Therefore, whereas the noun-verb distinction resulted simply in lower verb accuracy across groups, the 'manipulability' distinction revealed a 'double-dissociation' between patients and control participants. These results carry implications for theories of embodiment, lexico-semantic dissociations, and the organization of meaning in the brain. 相似文献
57.
In two experiments, we investigated the morphosyntactic decomposition and semantic composition of acoustically presented German compound words. A left-anterior negativity (LAN) was found in the ERP for gender incongruent, initial compound constituents although these constituents are syntactically irrelevant in German. This LAN provides online evidence for morphosyntactic decomposition. Experiment 1 showed also preliminary evidence for semantic composition, which was further investigated in Experiment 2 by comparing semantically transparent and opaque compounds. Transparent compounds elicited an increased negativity with a centroparietal maximum that occurred during the presentation of the head constituent. This negativity is suggested to reflect the semantic integration of compound constituents that is necessary after the constituents have been accessed separately. 相似文献
58.
The authors investigated how people remember real-life traumatic events. Adult residents (N = 145) of an Italian community that was flooded in fall of 2000 completed a questionnaire 3 years after the flood. Respondents briefly recounted their personal experiences with the flood and answered questions about emotional reactions to the flood, appraisal processes, and disaster exposure. Results showed that participants tended to recall experiences that occurred during the most critical phases of the disaster. The emotions most strongly experienced by respondents-sadness, fear, and surprise-were associated with specific appraisals. Content and amount of memories about flood experiences did not significantly vary as a function of flood exposure. Moreover, there was no significant relationship between memory quantity and emotional intensity. The authors discuss findings in the context of literature on traumatic memory and emotion. 相似文献
59.
Investigation of relations between personality traits and mental disorders can inform key issues in psychopathology research. However, it has been hindered by extensive correlations among the traits. Building on studies of affect-psychopathology relations (e.g., the tripartite model), an organizational framework is proposed to solve this problem with respect to anxiety pathology. To test the resulting model, associations between four traits (negative emotionality, positive emotionality, anxiety sensitivity, and negative evaluation sensitivity) and four anxiety symptoms (chronic worry, obsessive-compulsive symptoms, panic, and social anxiety) were examined in an undergraduate sample (N=907). Confirmatory factor analyses supported operationalizations of the constructs in this study. Examination of the trait-symptom links using hierarchical multiple regression analyses supported most of the predicted relations. Specifically, negative emotionality emerged as a general predictor that was significantly related to all four symptom dimensions. In contrast, anxiety sensitivity was specific to panic and worry, whereas negative evaluation sensitivity was specific to social anxiety and worry. Finally, positive emotionality was uniquely related to social anxiety. The model accounted for a substantial amount of variance in the symptoms and almost all of the covariation among them. 相似文献
60.
Eavesdropping can be defined as the extraction of information from the interactions between other individuals. It provides
a relatively cheap way of gathering relevant information for fitness enhancement. Here, we propose that obligate avian brood
parasites, which always lay their eggs in foreign nests of individuals of other species, may eavesdrop on their host sexual
signals to locate nests of high quality individuals in which to lay their parasitic eggs. Sexual signal variation can honestly
signal parental quality. Thus, by eavesdropping on sexual signals, parasites may select high quality foster parents for their
own offspring. Such a use of sexual signals within host populations by brood parasites differs from signal exploitation theory
that proposes that parasite only use signals to locate potential host independently from signaller quality. Here, we review
the avian literature concerning host choice within a host species by obligate avian brood parasites and find evidence for
host selection within individuals of a host species on the basis of cues potentially functioning as sexually selected traits,
or at least revealing parental abilities. We have also found support for the existence of benefits linked to host selection
by avian brood parasites. Finally, one study reported on the attenuation of a sexual ornament in host populations under strong
pressure by brood parasites. Most of these findings have been interpreted as evidence for host selection by avian brood parasites
based on the conspicuousness of sexual signals. We suggest, however, that these findings may in fact reveal eavesdropping
on host signalling performance by brood parasites which would use the information extracted to choose the better individuals
among conspecifics of a given host. This provides a new perspective for the study of host selection in obligate brood parasites,
and raises interesting questions for the study of animal cognition that would deserve experimental studies. 相似文献