Diagnostic imaging in the detection of parotid adenoma. Review of the literature and personal experience with the combined use of computerized tomography and MRI

In this report we reviewed the role of Ultrasonography, Computed Tomography, Magnetic Resonance and 99Tc-Sestamibi Scintigraphy for the detection of abnormal parathyroid glands in patients with biochemical evidence of hyperparathyroidism. We also report our personal experience with CT and RM.     

Information foraging.

Information foraging theory is an approach to understanding how strategies and technologies for information seeking, gathering, and consumption are adapted to the flux of information in the environment. The theory assumes that people, when possible, will modify their strategies or the structure of the environment to maximize their rate of gaining valuable information. The theory is developed by (a) adaptation (rational) analysis of information foraging problems and (b) a detailed process model (adaptive control of thought in information foraging [ACT-IF]). The adaptation analysis develops (a) information patch models, which deal with time allocation and information filtering and enrichment activities in environments in which information is encountered in clusters; (b) information scent models, which address the identification of information value from proximal cues; and (c) information diet models, which address decisions about the selection and pursuit of information items. ACT-IF is instantiated as a production system model of people interacting with complex information technology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of leading questions on prior memory: Evidence for the coexistence of inconsistent memory traces.

Previous studies have found that memory can be altered by leading questions that presuppose information inconsistent with originally presented memory materials. This phenomenon was examined to determine if memory disruption was due to the alteration of original memory by new inconsistent information. Also examined was the variation in this effect with the centrality of target materials. 48 undergraduates read high- and low-importance sentence targets embedded in texts, recalled the texts, were questioned about the materials, and later participated in a recognition task. Presented questions contained presuppositions that were consistent, inconsistent, or neutral with regard to targets. Recognition items were original targets, and foils were congruent with inconsistent question presuppositions. Inconsistent presuppositions did not produce significantly lower target hits than neutral presuppositions, but they did increase foil false alarms relative to neutrals, suggesting that both original and inconsistent new material coexisted in memory at recognition. Recognition results did not vary with the importance of the target material. False alarm rates following inconsistent presuppositions were higher among Ss who had previously failed to recall target information than for Ss recalling targets. This suggested that Ss may tag inconsistent information as false if original traces are retrievable at question time. (French abstract) (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of learning from examples in the acquisition of recursive programming skills.

Presents an analysis and simulation model of the verbal protocols of 2 college students and 1 8-yr-old S learning to program recursive functions. The model is formalized as a production system capable of acquiring new production rules based on problem-solving experience. The model and protocols suggest that (a) problem solving by analogy to worked-out examples is frequent in initial attempts by novices to write recursive functions; (b) different representations of examples are used to guide problem solving by analogy; and (c) performance on later problems reflects the particular representations used in problem solving by analogy on earlier problems. The protocols and simulations also suggest that learning is facilitated by using abstract representations of the structure of recursion examples to guide initial coding attempts. (French abstract) (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A knowledge-tracing model of learning from a social tagging system

We propose a user model to support personalized learning paths through online material. Our approach is a variant of student modeling using the computer tutoring concept of knowledge tracing. Knowledge tracing involves representing the knowledge required to master a domain, and, from traces of online user behavior, diagnosing user knowledge states as a profile over those elements. The user model is induced from documents tagged by an expert in a social tagging system. Tags identified with “expertise” in a domain can be used to identify a corpus of domain documents. That corpus can be fed to an automated process that distills a topic model representation characteristic of the domain. As a learner navigates and reads online material, inferences can be made about the degree to which topics in the target domain have been learned. We validate this knowledge tracing approach against data from a social tagging study. As part of this evaluation, we match the predictions of the knowledge-tracing model to individual participant responses made to individual question items used to test domain knowledge.     

Powers of 10: Modeling Complex Information-Seeking Systems at Multiple Scales

New models of information-seeking support systems offer two advantages: They move us from prescientific conceptual frameworks about information seeking to more rigorous scientific theories and predictive models while, at the same time, expanding the kinds of things we study and develop.     

You can't get there from here: Comments on R. W. Sperry's resolution of science and ethics.

Comments on R. W. Sperry's (see record 1989-00022-001) claims about the nature of cognitive science, assertions that science can prescribe moral values, and proclamations about ethics. It is argued that Sperry (1) made assertions that are largely at odds with mainstream conceptions of cognitive science, (2) failed to specify his meaning of moral responsibility without an acausal free will, and (3) failed to provide justifications for a deductive logic that allows one to derive moral values from scientific knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A theory of the measurement of knowledge content, access, and learning.

An approach to the measurement of knowledge content, knowledge access, and knowledge learning is developed. This approach has 2 elements: First, a theoretical view of cognition, called the Newell-Dennett framework, is described that is particularly favorable to the development of a measurement approach. A class of measurement models, based on Rasch modeling, is described that is particularly favorable to the development of cognitive theories. Knowledge content and access are viewed as determining the observable actions selected by an agent to achieve desired goals in observable situations. To the degree that models within the theory fit the data at hand, one considers measures of observed behavior to be manifestations of intelligent agents having specific classes of knowledge content and varying degrees of access to that knowledge. Although agents, environment, and knowledge are constitutively defined (in terms of one another), successful application of the theory affords separation of parameters associated with the person from those associated with the environment. Two examples of measurement models developed within the approach are discussed that address the evolution of cognitive skill, strategy choice and application, and developmental changes in mixtures of strategy use. (PsycINFO Database Record (c) 2010 APA, all rights reserved)