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171.
Recent experiments have been used to “edit” genomes of various plant, animal and other species, including humans, with unprecedented precision. Furthermore, editing the Cas9 endonuclease gene with a gene encoding the desired guide RNA into an organism, adjacent to an altered gene, could create a “gene drive” that could spread a trait through an entire population of organisms. These experiments represent advances along a spectrum of technological abilities that genetic engineers have been working on since the advent of recombinant DNA techniques. The scientific and bioethics communities have built substantial literatures about the ethical and policy implications of genetic engineering, especially in the age of bioterrorism. However, recent CRISPr/Cas experiments have triggered a rehashing of previous policy discussions, suggesting that the scientific community requires guidance on how to think about social responsibility. We propose a framework to enable analysis of social responsibility, using two examples of genetic engineering experiments. 相似文献
172.
Sweeney AE 《Science and engineering ethics》2006,12(3):435-464
Continuing advances in human ability to manipulate matter at the atomic and molecular levels (i.e. nanoscale science and engineering)
offer many previously unimagined possibilities for scientific discovery and technological development. Paralleling these advances
in the various science and engineering subdisciplines is the increasing realization that a number of associated social, ethical,
environmental, economic and legal dimensions also need to be explored. An important component of such exploration entails
the identification and analysis of the ways in which current and prospective researchers in these fields conceptualize these
dimensions of their work. Within the context of a National Science Foundation funded Research Experiences for Undergraduates
(REU) program in nanomaterials processing and characterization at the University of Central Florida (2002–2004), here I present
for discussion (i) details of a “nanotechnology ethics” seminar series developed specifically for students participating in
the program, and (ii) an analysis of students’ and participating research faculty’s perspectives concerning social and ethical
issues associated with nanotechnology research. I conclude with a brief discussion of implications presented by these issues
for general scientific literacy and public science education policy. 相似文献
173.
Cognitive functioning in delusions: a longitudinal analysis 总被引:2,自引:0,他引:2
BACKGROUND: This study explored the longitudinal course of the relationship between delusions and different aspects of cognitive functioning. METHODS: Deluded patients were compared to psychiatric and non-clinical controls on three tasks: negative priming, a probabilistic judgement task (the 'beads' task), and the pragmatic inference task (PIT). All groups were tested at two time points, once when actively symptomatic, and once when in remission. RESULTS: Deluded individuals exhibited a 'jump-to-conclusions' (JTC) reasoning bias: i.e., they made decisions on the basis of limited evidence and were more likely to revise their estimates when faced with disconfirmatory evidence. This JTC bias remained stable over time, although probability judgments seemed to normalise in remission. No deficits in cognitive inhibition were found on negative priming. The deluded group displayed an excessive self-focus on the PIT at both time points, but did not show a depressive attributional style. Only a small sub-sample, characterised by the "bad-me" type of paranoia [Trower & Chadwick, 1995 Clinical Psychology: Science and Practice, 2, 263-278.], demonstrated depressive schemas when symptomatic, but no longer did so when remitted. Few relationships were found between tasks, suggesting that different areas of functioning are relatively independent. The only measures associated with delusion symptom scores were from the 'beads' task. CONCLUSIONS: Overall these findings suggest that the JTC bias is a stable factor associated with delusional thinking, while the depressive attributional style characteristic of a small sub-sample of paranoid patients fluctuates with delusional course. 相似文献
174.
Dorahy MJ McCusker CG Loewenstein RJ Colbert K Mulholland C 《Behaviour research and therapy》2006,44(5):749-764
Using an experimentally based, computer-presented task, this study assessed cognitive inhibition and interference in individuals from the dissociative identity disorder (DID; n=12), generalized anxiety disorder (GAD; n=12) and non-clinical (n=12) populations. Participants were assessed in a neutral and emotionally negative (anxiety provoking) context, manipulated by experimental instructions and word stimuli. The DID sample displayed effective cognitive inhibition in the neutral but not the anxious context. The GAD sample displayed the opposite findings. However, the interaction between group and context failed to reach significance. There was no indication of an attentional bias to non-schema specific negative words in any sample. Results are discussed in terms of the potential benefit of weakened cognitive inhibition during anxious arousal in dissociative individuals. 相似文献
175.
Exposure to panic symptoms (interoceptive exposure) is often included as part of treatment for panic disorder (PD), although little is known about the relative effects of particular symptom induction exercises. This study describes responses of individuals with PD and nonclinical controls to 13 standard symptom induction exercises and 3 control exercises. Generally, individuals with PD responded more strongly to symptom induction exercises than did controls. The exercises producing the most fear included spinning, hyperventilation, breathing through a straw, and using a tongue depressor. This study also reports findings regarding specific symptoms triggered by each exercise, the percentage of participants reporting fear during each exercise, and predictors of fear. 相似文献
176.
Abramowitz JS Khandker M Nelson CA Deacon BJ Rygwall R 《Behaviour research and therapy》2006,44(9):1361-1374
Cognitive models of obsessive-compulsive disorder (OCD) posit that specific kinds of dysfunctional beliefs (e.g., pertaining to responsibility and the significance of intrusive thoughts) underlie the development of this disorder. The present study was designed to prospectively evaluate whether dysfunctional beliefs thought to underlie OCD act as a specific vulnerability factor in the pathogenesis of obsessive-compulsive symptomatology. Eighty-five individuals were prospectively followed over a period of time thought to be associated with an increased onset of OCD symptoms -- childbirth and the postpartum. The majority of these new mothers and fathers experienced intrusive infant-related thoughts and performed neutralizing behaviors similar to, but less severe than, those observed in OCD. Scores on a measure of dysfunctional beliefs thought to underlie OCD predicted the development of obsessive-compulsive symptoms after controlling for pre-existing OCD symptoms, anxiety, and depression. Dysfunctional beliefs also predicted the severity of checking, washing, and obsessional OCD symptom dimensions, but not neutralizing, ordering, or hoarding symptom dimensions. These data provide evidence for specific dysfunctional beliefs as risk factors in the development of some types of OCD symptoms. 相似文献
177.
The present study investigates the effectiveness of a 3-h cognitive behavioral workshop for individuals, ages 18-22, with subclinical obsessions and compulsions. It was hypothesized that, compared to individuals in an assessment-only waitlist group (n = 42), individuals assigned to the workshop group (n = 43) would experience a significant decrease in obsessive-compulsive (OC) symptomatology, comorbidity, and thought action fusion endorsement at 1-month and 5-month follow-up assessments. An additional outcome of interest was the number of incident cases of obsessive-compulsive disorder (OCD) over the course of the study. The results indicated that the workshop group reported a significantly fewer number of OC symptoms at 5-month follow-up and endorsed significantly less thought action fusion at both follow-up points. However, there were no differences between groups in severity of OC symptoms and number of comorbid diagnoses endorsed. Only one incident case of OCD was observed during the study, from a participant in the waitlist group. These results are discussed in reference to treatment of subclinical anxiety symptoms. 相似文献
178.
Cognitive behavioural conceptualisations of grief propose that negative cognitions and avoidance strategies play a key role in emotional problems after bereavement. In the current study, this assumption was examined. Ninety-seven individuals who had lost a relative less than 5 months ago completed questionnaires tapping background and loss-related variables, negative cognitions (about the self, life, the future, and one's own grief reactions), avoidance, and symptoms of complicated grief (CG) and depression. Of these mourners, 70 people (72%) completed symptom measures again 6 months later at T2 (7-10 months after the loss), and 60 (62%) completed symptoms measures still 9 months later at T3 (16-19 months after the loss). Among other things, results showed that all four cognitive variables and the avoidance variable were strongly associated with concurrent and prospective symptom levels, even when the influence of relevant background/loss-related variables was controlled. In addition, independent of initial symptom levels, most of the cognitive variables predicted later CG and depression. The avoidance variable only predicted additional variance in depression at T3 beyond T1 symptom levels. Findings indicate that negative cognitions are important in emotional problems after bereavement and that the role of avoidance in the development of these problems needs further scrutiny. 相似文献
179.
Existing frameworks for explaining spatial knowledge acquisition in a new environment propose either stage-like or continuous development. To examine the spatial microgenesis of individuals, a longitudinal study was conducted. Twenty-four college students were individually driven along two routes in a previously unfamiliar neighborhood over 10 weekly sessions. Starting Session 4, they were also driven along a short connecting route. After each session, participants estimated spatial properties of the routes. Some participants' knowledge improved fairly continuously over the sessions, but most participants either manifested accurate metric knowledge from the first session or never manifested accurate metric knowledge. Results are discussed in light of these large individual differences, particularly with respect to the accuracy and development of integrated configurational knowledge. 相似文献
180.
Seok B 《Cognitive Science》2006,30(2):347-380
Since the publication of Fodor's (1983) The Modularity of Mind, there have been quite a few discussions of cognitive modularity among cognitive scientists. Generally, in those discussions, modularity means a property of specialized cognitive processes or a domain-specific body of information. In actuality, scholars understand modularity in many different ways. Different characterizations of modularity and modules were proposed and discussed, but they created misunderstanding and confusion. In this article, I classified and analyzed different approaches to modularity and argued for the unity of modularity. Modularity is a multidimensional property consisting of features from several dimensions specifying different aspects of cognition. Among those, there are core features of modularity, and these core features form a cross-dimensional unity. Despite the diverse and liberal characterizations, modularity contributes to cognitive science because of the unity of the core features. 相似文献