专家医生的知识结构及诊断推理方式

医学专长研究中“中间者效应”的发现,引发了研究者对专家医生知识结构的探讨。在“知识打包”的基础上,医生的临床知识以“疾病脚本”的方式组织起来。随着临床经验的增加,专家医生积累了丰富的疾病脚本。在临床诊断中,他们无需对病人所有的体征和症状进行仔细地和系统地分析,而是通过非分析性的推理方式——“模式识别”或“样例识别”便可自动激活与之匹配的疾病脚本,据此对病人做出迅速而准确的诊断。医学专长的本质就在于专家医生以“疾病脚本”的方式组织起来的知识结构。“适应性专长”代表了未来医学专长研究的新方向     

Strategies in Syllogistic Reasoning

This paper is about syllogistic reasoning, i.e., reasoning from such pairs of premises as, All the chefs are musicians; some of the musicians are painters. We present a computer model that implements the latest account of syllogisms, which is based on the theory of mental models. We also report four experiments that were designed to test this account. Experiments 1 and 2 examined the strategies revealed by the participants' use of paper and pencil as aids to reasoning. Experiment 3 used a new technique to externalize thinking. The participants had to refute, if possible, putative conclusions by constructing external models that were examples of the premises but counterexamples of the conclusions. Experiment 4 used the same techniques to examine the participants' strategies as they drew their own conclusions from syllogistic premises. The results of the experiments showed that individuals not trained in logic can construct counterexamples, that they use similar operations to those implemented in the computer model, but that they rely on a much greater variety of interpretations of premises and of search strategies than the computer model does. We re-evaluates current theories of syllogistic reasoning in the light of these results.     

Knowledge Grounded on Pure Reasoning

In this paper, I deal with epistemological issues that stem from the hypothesis that reasoning is not only a means of transmitting knowledge from premise‐beliefs to conclusion‐beliefs but also a primary source of knowledge in its own right. The idea is that one can gain new knowledge on the basis of suppositional reasoning. After making some preliminary distinctions, I argue that there are no good reasons to think that purported examples of knowledge grounded on pure reasoning are just examples of premise‐based inferences in disguise. Next, I establish what kinds of true propositions can to a first approximation be known on the basis of pure reasoning. Finally, I argue that beliefs that are competently formed on the basis of suppositional reasoning satisfy both externalist and internalist criteria of justification.     

Reasoning and Instruction in Medical Curricula

We describe two experiments that examine the knowledge and explanatory processes of students in two medical schools with different modes of instruction. One school had a conventional curriculum with basic science courses taught 1 '/2 years before the clinical training; the other had a problem-based learning curriculum with basic science taught in the context of clinical problems and general problem-solving strategies involving knowledge elaboration and hypothetico-deductive reasoning. Both before and after being exposed to relevant basic science information, students were asked to provide diagnostic explanations of a clinical case. In this study, students in the problem-based learning curriculum reasoned in a manner consistent with the way they were taught, using a backward directed pattern of reasoning and extensive elaborations based on detailed biomedical information. However; these students had a greater tendency to commit errors of scientific fact, to generate less coherent explanations, and to use flawed patterns of explanation, such as circular reasoning. These results are viewed as reflecting the operation of two factors: context and method of instruction. The interaction between these factors is expressed in terms of the hypothesis that basic science and clinical knowledge constitute two different worlds.     

Rules for Reasoning from Knowledge and Lack of Knowledge

In this paper, the traditional view that argumentum ad ignorantiam is a logical fallacy is challenged, and lessons are drawn on how to model inferences drawn from knowledge in combination with ones drawn from lack of knowledge. Five defeasible rules for evaluating knowledge-based arguments that apply to inferences drawn under conditions of lack of knowledge are formulated. They are the veridicality rule, the consistency of knowledge rule, the closure of knowledge rule, the rule of refutation and the rule for argument from ignorance. The basic thesis of the paper is that knowledge-based arguments, including the argument from ignorance, need to be evaluated by criteria for epistemic closure and other evidential rules that are pragmatic in nature, that need to be formulated and applied differently at different stages of an investigation or discussion. The paper helps us to understand practical criteria that should be used to evaluate all arguments based on knowledge and/or ignorance.

Interviewer Knowledge and Preschoolers' Reasoning About Knowledge States Moderate Suggestibility

Fifty-one preschoolers listened to a story and were interviewed about the details by a knowledgeable and a naı̈ve interviewer. Half the questions were straightforward and half were misleading. One-week later, children completed a recognition test to measure story memory and a set of theory-of-mind tasks to measure reasoning about mental states related to knowing. All children showed a misinformation effect at the initial interview. At the recognition test, a knowledgeable interviewer misled children who passed false-belief tasks more often than a naı̈ve interviewer did. Knowledgeable and naı̈ve interviewers misled children who failed false-belief tasks equally often. False-belief scores predicted the tendency to be misled more often by a knowledgeable interviewer relative to a naı̈ve interviewer, after controlling for age and memory when not misled. Elaborated cognitive processing and/or memory source monitoring may mediate the results.     

情绪调节策略对推理的影响

研究使用两种推理题作为实验材料.比较了负性情绪诱发状态下情绪调节策略使用与否以及不同情绪调节策略对推理的影响.结果发现,认知重评组的成绩好于表达抑制组和无调节组,存在显著差异;表达抑制组与无调节组之间不存在差异.此外,在表达抑制组上,男生的图形推理成绩好于女生,存在显著的性别差异.因此,个体不同推理任务的成绩与是否使用调节策略、使用什么策略及性别有关.     

医学生医学伦理推理能力调查研究

采用中间概念测量法,围绕病人自主权、保密、有利、公平分配四个中间概念,对我国S省某医学院1108名医学生医学伦理推理行为表现和动机水平进行调查。调查发现,医学生在面对多重叠加的复杂伦理问题时,推理能力相对较差;对医学伦理行为动机的判定优于对行为的判定;医学生的年级、性别、医学伦理负面事件的干扰等因素,都会对其医学伦理推理能力产生影响。基于此,医学伦理教育应构建全方位、全环境的教育模式,明确教学目标、创新教育方式以加强伦理推理能力培养,充分利用隐性课程的积极作用。

     

Complete Axiomatizations for Reasoning about Knowledge and Branching Time

Sound and complete axiomatizations are provided for a number of different logics involving modalities for the knowledge of multiple agents and operators for branching time, extending previous work of Halpern, van der Meyden and Vardi [to appear, SIAM Journal on Computing] for logics of knowledge and linear time. The paper considers the system constraints of synchrony, perfect recall and unique initial states, which give rise to interaction axioms. The language is based on the temporal logic CTL*, interpreted with respect to a version of the bundle semantics.     

Knowledge Argument: Scientific Reasoning and the Explanatory Gap

It is easy to accept that scientific reasoning cannot determine the characteristics of subjective experiences in cases like Broad’s archangel or Jackson’s Mary. The author questions why this seems to be evident and discusses the differences between these cases and ordinary scientific work, where future states of studied systems can be predicted in phenomenal terms. He concludes that important limitations of scientific reasoning are due to the inadequacy of human sensorial apparatus for representing physical reality. Such inadequacies were more evident in Mary’s case, but are always present, and entail the existence of the explanatory gap.     

Cognitive Structure,Content Knowledge,and Classificatory Reasoning

Classificatory reasoning was studied in 58 children, 7 and 8 years old, who differed in operational level as well as in expertise. Knowledge about dinosaurs was used to distinguish expertise level. The children's performance on class-inclusion tasks involving the dinosaur content was a function of operational level. An overall effect of expertise was found for children's performance on class-membership measures. Furthermore, on the class-membership measures, expertise did not significantly influence the performance of children at the concrete-operational level, but it did for children at the pre-operational level. The results suggest that domain-specific knowledge and operational level may have different but interacting influences on children's classificatory reasoning.     

Recognizing Racit Knowledge in Medical Epistemology

The evidence-based medicine movement advocates basing all medical decisions on certain types of quantitative research data and has stimulated protracted controversy and debate since its inception. Evidence-based medicine presupposes an inaccurate and deficient view of medical knowledge. Michael Polanyi’s theory of tacit knowledge both explains this deficiency and suggests remedies for it. Polanyi shows how all explicit human knowledge depends on a wealth of tacit knowledge which accrues from experience and is essential for problem solving. Edmund Pellegrino’s classic treatment of clinical judgment is examined, and a Polanyian critique of this position demonstrates that tacit knowledge is necessary for understanding how clinical judgment and medical decisions involve persons. An adequate medical epistemology requires much more qualitative research relevant to the clinical encounter and medical decision making than is currently being done. This research is necessary for preventing an uncritical application of evidence-based medicine by health care managers that erodes good clinical practice. Polanyi’s epistemology shows the need for this work and provides the structural core for building an adequate and robust medical epistemology that moves beyond evidence-based medicine.An erratum to this article can be found at     

Spatial Proportional Reasoning Is Associated With Formal Knowledge About Fractions

Proportional reasoning involves thinking about parts and wholes (i.e., about fractional quantities). Yet, research on proportional reasoning and fraction learning has proceeded separately. This study assessed proportional reasoning and formal fraction knowledge in 8- to 10-year-olds. Participants (N = 52) saw combinations of cherry juice and water in displays that highlighted either part–whole or part–part relations. Their task was to indicate on a continuous rating scale how much each mixture would taste of cherries. Ratings suggested the use of a proportional integration rule for both kinds of displays, although more robustly and accurately for part–whole displays. The findings indicate that children may be more likely to scale proportional components when being presented with part–whole as compared with part–part displays. Crucially, ratings for part–whole problems correlated with fraction knowledge, even after controlling for age, suggesting that a sense of spatial proportions is associated with an understanding of fractional quantities.     

The Role of Domain-Specific Knowledge in Generative Reasoning About Complicated Multileveled Phenomena

Promoting the ability to reason generatively about novel phenomena and problems students may encounter in their everyday lives is a major goal of science education. This goal proves to be a formidable challenge in domains, such as molecular genetics, for which the accumulated scientific understandings are daunting in both amount and complexity. To develop effective instruction that fosters generative reasoning we need to have a sound understanding of the types of knowledge in the domain that are critical for such reasoning. In this study I examined the ensemble of knowledge, both general and domain-specific, undergraduate students employed in reasoning about problems in genetics. I found that students initially formulate a solution in terms that are not domain specific and that serve as a frame–solution frame–that outlines and constrains a more specific and domain-appropriate explanation. This solution frame is then filled in with two powerful forms of domain-specific knowledge I term: domain-specific heuristics and domain-specific explanatory schemas. These knowledge forms embody understandings of central mechanisms and entities in molecular genetics. By invoking these domain-specific knowledge forms, students were able to reason about a variety of both familiar and novel genetics problems. I present a cognitive model that highlights the role of these powerful conceptual understandings in promoting generative reasoning in genetics.