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991.
Efrat Dagan Daphna Birenbaum-Carmeli Eitan Friedman Baruch Feldman 《Journal of genetic counseling》2017,26(5):1070-1079
To describe factors associated with preimplantation genetic diagnosis (PGD) decisions among Jewish Israeli BRCA1/2 carriers or spouses of a male carrier, we contacted all women who initiated PGD consultation for embryonic BRCA1/2 mutation detection at Sheba Medical Center, prior to March 2014. Applying a qualitative approach, we asked women to elaborate on the factors they considered in either opting for PGD or discontinuing the screening procedure. Participants were 18 Jewish Israeli women; 14 were carriers of one of the Ashkenazi founder mutations in BRCA1/2, and four were spouses of male mutation carriers, who underwent at least one cycle of PGD. Prior to seeking PGD, ten of the women had no children. At the time of the interview, all but three had at least one child. Three factors emerged as key motivators for PGD: having witnessed the disease in a close relative (n = 12); prior IVF treatment for infertility (n = 12); and having pre-existing frozen embryos (n = 6). Ten women withdrew from the PGD process due to clinical, logistical, and financial reasons. In conclusion, most women decided to withdraw from PGD instead of continuing until a successful conception was achieved. Those who opted for PGD attributed their discontinuation of further screening to the emotional burden that is greatly intensified by practical difficulties. 相似文献
992.
Melanie C. Green Jessica Hilken Hayley Friedman Karly Grossman Josephine Gasiewskj Rob Adler John Sabini 《Journal of applied social psychology》2005,35(3):445-462
Ersatz social engagement theory (Green & Brock, 1998, 2003) suggests that individuals may be drawn to mediated interactions because of their ease, lack of risk, and immediate gratification, but that these interactions may be less rewarding over the long term. In Study 1 ( N = 42), participants' moods were measured before and after engaging in a conversation with a stranger either online (instant messenger) or face to face. Participants became slightly less tense and less angry regardless of which condition they were in, but significantly happier when they were in the instant messenger (1M) condition. The increased happiness after an IM rather than face-to-face conversation was especially pronounced among women. Study 2 ( N = 101) was a survey of students' Internet use and other extracurricular activities. Students did not appear to be substituting Internet use for other forms of extracurricular engagement. However, IM use was associated with feeling that one used the Internet too much, and reduced life satisfaction. 相似文献
993.
Paul L. Harris Samuel Ronfard Deborah Bartz 《European Journal of Developmental Psychology》2017,14(2):221-232
When do children acquire an understanding of knowledge and ignorance? We analyzed the early development of children’s spontaneous references to knowing and not knowing and conclude that 2-year-olds talk explicitly and cogently about their own knowledge as well as that of an interlocutor. Two-year-olds also admit their own ignorance. Moreover, consistent with their realization that an informant may know what they do not, 2-year-olds ask many information-seeking questions. Finally, we discuss children’s receptivity and skepticism, especially toward the counterintuitive claims of an adult. We conclude that children’s conception of knowledge and ignorance begins early but undergoes protracted refinement. 相似文献
994.
Nicolas A. McNair Patrick T. Goodbourn Lauren T. Shone Irina M. Harris 《Attention, perception & psychophysics》2017,79(1):100-116
We used the attentional blink (AB) paradigm to investigate the processing stage at which extraction of summary statistics from visual stimuli (“ensemble coding”) occurs. Experiment 1 examined whether ensemble coding requires attentional engagement with the items in the ensemble. Participants performed two sequential tasks on each trial: gender discrimination of a single face (T1) and estimating the average emotional expression of an ensemble of four faces (or of a single face, as a control condition) as T2. Ensemble coding was affected by the AB when the tasks were separated by a short temporal lag. In Experiment 2, the order of the tasks was reversed to test whether ensemble coding requires more working-memory resources, and therefore induces a larger AB, than estimating the expression of a single face. Each condition produced a similar magnitude AB in the subsequent gender-discrimination T2 task. Experiment 3 additionally investigated whether the previous results were due to participants adopting a subsampling strategy during the ensemble-coding task. Contrary to this explanation, we found different patterns of performance in the ensemble-coding condition and a condition in which participants were instructed to focus on only a single face within an ensemble. Taken together, these findings suggest that ensemble coding emerges automatically as a result of the deployment of attentional resources across the ensemble of stimuli, prior to information being consolidated in working memory. 相似文献
995.
Anna Thorwart Metin Uengoer Evan J. Livesey Justin A. Harris 《Quarterly journal of experimental psychology (2006)》2017,70(7):1366-1379
Participants in two human goal-tracking experiments were simultaneously trained with negative patterning (NP) and positive patterning (PP) discriminations (A+, B+, AB–, C–, D–, CD+). Both elemental and configural models of associative learning predict a PP advantage, such that NP is solved less readily than PP. However, elemental models like the unique cue approach additionally predict responding in AB– trials to be initially stronger than that in A+ and B+ trials due to summation of associative strength. Both experiments revealed a PP advantage and a strong summation effect in AB– trials in the first half of the experiments, irrespective of whether the same US was used for both discriminations (Experiment 1) or two different USs (Experiment 2). We discuss that the correct predictions of the unique cue approach are based on its assumptions of non-normalized and context-independent stimulus processing rather than elemental processing per se. 相似文献
996.
The placebo effect is an important phenomenon whereby real changes occur in response to an otherwise inert intervention. Despite increasing research attention, it remains unclear exactly which processes are amenable to placebo effects. The current study tested whether an instructional manipulation could produce placebo effects on a nonconscious cognitive task, namely implicit learning. Four hundred and sixty-four university students completed a visual search task while smelling an odor or no odor, in alternating blocks. Unknown to them, the task contained a contingency whereby on half the trials the target's location was cued by the pattern of distractors, which was achieved by repeating some configurations of targets and distractors. Prior to the task, participants received positive, negative, or no information about the odor's possible effects on performance. Those given positive information demonstrated faster reaction times on cued trials than other participants. Those given negative information showed slower reaction times on cued trials compared with participants given no information. Further, the cuing effect appeared to be nonconscious, with participants' ability to recognize the repeated configurations equivalent to chance and no evidence that performance on a recognition test was related to the magnitude of the cuing effect. This suggests that instructional manipulations can produce placebo effects on some nonconscious processes. 相似文献
997.
To navigate a world filled with private property, children must be able to assign ownership information to objects and update that information when appropriate. In this chapter, the authors propose that children include ownership as an attribute of their object representations. Children can learn about ownership attributes either by witnessing owners acting on their property, a visual source, or by receiving information from the testimony of others, a verbal source. The authors consider the differences between these two forms of information and how they might conflict at the representational level, leading to difficulties in learning about ownership. 相似文献
998.
999.
1000.
Michael Friedman 《Synthese》2011,180(2):249-263
Both realists and instrumentalists have found it difficult to understand (much less accept) Carnap’s developed view on theoretical
terms, which attempts to stake out a neutral position between realism and instrumentalism. I argue that Carnap’s mature conception
of a scientific theory as the conjunction of its Ramsey sentence and Carnap sentence can indeed achieve this neutral position.
To see this, however, we need to see why the Newman problem raised in the context of recent work on structural realism is
no problem for Carnap’s conception; and we also need to locate Carnap’s work on theoretical terms within his wider program
of Wissenschaftslogik or the logic of science. 相似文献