The meta-level versus object-level distinction (and other issues) in formulations of metacognition.

Replies to comments by A. B. Newberg et al (see record 1997-02873-011) and A. D. Kornfeld (see record 1997-02873-012) on T. O. Nelson's paper (see record 83-26608) on consciousness and metacognition. Nelson addresses each of Newberg's comments, and asserts that one can make good use of the distinction between object-level and meta-level processing without taking any stance about an ultimate meta-level. Nelson also explains his disagreement with Kornfeld's comments on Wilhelm Wundt and Dunlap. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Understanding coronary artery movement: a knowledge-based approach

The aim of this paper is to describe a knowledge-based system that interprets three-dimensional (3D) coronary artery movement, using data from digital subtraction angiography image sequences. Dynamic information obtained from artery centerline 3D reconstruction and optical flow estimation, is classified according to experimental evidence indicating that artery displacements are quasi-homogeneous by a segment analysis. Characteristic motion features like displacement direction, perpendicular/radial components, rotation direction, curvature and torsion are qualitatively described from an image sequence using symbolic labels. These facts are then related and interpreted using anatomical-functional knowledge provided by a specialist, as well as spatial and temporal knowledge, applying spatio-temporal reasoning schemes. Facts, knowledge and reasoning rules are stated in a declarative form. Detailed examples of local and global interpretation results, using a real reconstructed angiographic biplane image sequence are presented in order to illustrate how our system suitably interprets coronary artery dynamic behavior.     

Two kinds of attention in Pavlovian conditioning: Evidence for a hybrid model of learning.

Four appetitive Pavlovian conditioning experiments with rats examined the rate at which the discrimination between compounds AY and AX was solved relative to the discrimination between compounds AY and BY. In Experiments 1 and 2, these discriminations were preceded by training in which A and B were continuously reinforced and X and Y were partially reinforced. Consistent with the Pearce and Hall (1980) model, the results showed that the AY/AX discrimination was solved more readily than the AY/BY discrimination. In Experiments 3 and 4, the discriminations were preceded by feature-positive training in which trials with AX and BY signaled food but trials with X and Y did not. Consistent with the Mackintosh (1975) model, the results showed that the AY/BY discrimination was solved more readily than the AY/AX discrimination. These results are discussed with respect to a hybrid model of conditioning and attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Genetic architecture of learning and delayed recall: A twin study of episodic memory.

Objective: Although episodic memory is often conceptualized as consisting of multiple component processes, there is a lack of understanding as to whether these processes are influenced by the same or different genetic determinants. The aim of the present study was to utilize multivariate twin analyses to elucidate the degree to which learning and delayed recall, two critical measures of episodic memory performance, have common or different genetic and environmental influences. Method: Participants from the Vietnam Era Twin Study of Aging (314 monozygotic twin pairs, 259 dizygotic twin pairs, and 47 unpaired twins) were assessed using the second edition of the California Verbal Learning Test. Mean age at the time of the evaluation was 55.4 years (SD = 2.5). Results: Model fitting revealed the presence of a higher-order latent factor influencing learning, short- and long-delay free recall, with a heritability of .36. The best-fitting model also indicated specific genetic influences on learning, which accounted for 10% of the overall variance. Given that learning involves the acquisition and retrieval of information, whereas delayed recall involves only retrieval, we conclude that these specific effects are likely to reflect genes that are specific to acquisition processes. Conclusion: These results demonstrate that even in nonclinical populations, it is possible to differentiate component processes in episodic memory. These different genetic influences may have implications for gene association studies, as well as other genetic studies of cognitive aging and disorders of episodic memory such as Alzheimer's disease or mild cognitive impairment. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

The use of a computerized brain atlas to support knowledge-based training in radiology

Trainers of radiologists face the particular challenges of teaching normal and abnormal appearance for a variety of imaging modalities, providing access to a large appropriately-indexed case library, and teaching a consistent approach to the reporting of cases. The computer has the potential to address these issues, to supplement conventional teaching of radiology by providing case-based tutoring and diagnostic support based on a large library of images of normal and abnormal anatomy, described in a consistent terminology. The paper presents a new approach to computer-based training in radiology that combines a knowledge-based tutor with an on-line medical atlas. It describes two existing computer systems, the MR Tutor and ATLAS, and discusses the medical, computational, epistemic, and pedagogic issues involved in developing a combined Atlas-Tutor. Integrating an atlas with a training system could significantly improve the teaching and support offered, but practical difficulties include the need to merge knowledge representations and to incorporate techniques for registering atlas plates on images that exhibit abnormalities. The paper addresses these problems, and concludes by indicating how the Atlas-Tutor might be employed in practical radiology training.     

教育是知识产业:中国教育发展观的新突破

在1999年6月召开的第三次全国教育工作会议上,江泽民同志明确指出:"各级党委和政府,都要将教育纳入战略发展重点和现代化教育的整体布局之中,切实把教育作为先导性、全局性、基础性的知识产业和关键的基础设施,摆在优先发展的战略重点地位."这种崭新的教育产业观,在更深的层次上揭示了教育在未来经济发展中的战略意义,赋予了"教育优先发展"战略以新的时代内涵,为加强教育自身的发展步伐,加大教育改革的力度,提供了科学的理论依据和实践依据,标志着全党、全国人民对教育的战略重点地位在认识上的新突破.     

Supporting visual and verbal learning preferences in a second-language multimedia learning environment.

English-speaking college students who were enrolled in a German course read a 762-word German language story presented by a computer program. For key words in the story, students could choose to see a translation on the screen in English (i.e., verbal annotation) or view a picture or video clip representing the word (i.e., visual annotation), or both. Students remembered word translations better when they had selected both visual and verbal annotations during learning than only 1 or no annotation; students comprehended the story better when they had the opportunity to receive their preferred mode of annotation. Results are consistent with a generative theory of multimedia learning that assumes that learners actively select relevant verbal and visual information, organize the information into coherent mental representations, and integrate these newly constructed visual and verbal representations with one another. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Microvascular architecture of hepatic metastases in a mouse model

Development of effective treatment for hepatic metastases can be initiated by a better understanding of tumour vasculature and blood supply. This study was designed to characterise the microvascular architecture of hepatic metastases and observe the source of contributory blood supply from the host. Metastases were induced in mice by an intrasplenic injection of colon carcinoma cells (10(6) cells/ml.) Vascularization of tumours was studied over a three week period by scanning electron microscopy of microvascular corrosion casts. Metastatic liver involvement was observed initially within a week post induction, as areas approximately 100 microns in diameter not perfused by the casting resin. On histology these spaces corresponded to tumour cell aggregates. The following weeks highlighted the angiogenesis phase of these tumours as they received a vascular supply from adjacent hepatic sinusoids. Direct sinusoidal supply of metastases was maintained throughout tumour growth. At the tumour periphery most sinusoids were compressed to form a sheath demarcating the tumour from the hepatic vasculature. No direct supply from the hepatic artery or the portal vein was observed. Dilated vessels termed vascular lakes dominated the complex microvascular architecture of the tumours, most tapering as they traversed towards the periphery. Four vascular branching patterns could be identified as true loops, bifurcations and trifurcations, spirals and capillary networks. The most significant observation in this study was the direct sinusoidal supply of metastases, together with the vascular lakes and the peripheral sinusoidal sheaths of the tumour microculature.     

Muscle architecture and function in humans

We describe a 58-year-old woman who developed Wegener's granulomatosis (WG) complicated by a perforation of the transverse colon caused by necrotizing granulomatous vasculitis. In addition, her colon lesion continued in spite of high dose corticosteroid and cyclophosphamide therapy. She was admitted to our hospital because of her severe tonsillitis in Dec., 1994. She was diagnosed as having WG because she had oral ulcer, antibiotics-resistant lung infiltration, renal dysfunction and positive C-ANCA. Just after we started high dose steroid therapy, the transverse colon was perforated because of vasculitis, and she underwent emergency operation. Many vasculitic lesions were found in the small intestine, colon, and mesenterium. The disease was improved by corticosteroid and cyclophosphamide therapy except for a sustained ulcer with necrotizing vasculitis in the sigmoid colon region even 1 year after the operation. Although WG rarely complicates digestive tract lesions as initial manifestations, they reach 12% of the causes of death of WG in Japan. Therefore, we should take care of digestive tract lesions when we follow-up patients with WG.     

Observation learning in day-old chicks using a one-trial passive avoidance learning paradigm

The ATP-binding cassette (ABC) transporters belong to a large superfamily of proteins which share a common function and a common nucleotide-binding domain. The CvaB protein from Escherichia coli is a member of the bacterial ABC exporter subfamily and is essential for the export of the peptide antibiotic colicin V. Here we report that, surprisingly, the CvaB carboxyl-terminal nucleotide-binding domain (BCTD) can be preferentially cross-linked to GTP but not to ATP at low temperatures. The cross-linking is Mg2+ and Mn2+ dependent. However, BCTD possesses similar GTPase and ATPase activities at 37 degrees C, with the same kinetic parameters and with similar responses to inhibitors. Moreover, a point mutation (D654H) in CvaB that completely abolishes colicin V secretion severely impairs both GTPase and ATPase activities in the corresponding BCTD, indicating that the two activities are from the same enzyme. Interestingly, hydrolysis activity of ATP is much more cold sensitive than that of GTP: BCTD possesses mainly GTP hydrolysis activity at 10 degrees C, consistent with the cross-linking results. These findings suggest a novel mechanism for an ABC protein-mediated transport with specificity for GTP hydrolysis.     

Problem-based learning in a social medicine course--a concept for improving learning achievement and practice relevance

In many medical curricula around the world, problem-based learning (PBL), i.e. inductive, usually interdisciplinary learning based on real or constructed cases, has been shown to improve the acquisition of knowledge. Additionally, it is valued positively by students. On the other hand, lecturing is usually valued negatively. Teaching of epidemiology and social medicine is further handicapped by the fact that students consider it irrelevant. In 1994/95, one of 18 social medicine courses for fifth year medical students at Hannover Medical School was problem-based. The following "cases" were used: 1. rheumatic patient with various social medical problems (losing sick pay, receiving status as handicapped person, early retirement etc.), 2. cluster of patients with leukaemia in the surroundings of a nuclear power plant and 3. recent newspaper articles on the effects of the 1993 Health Care Reform Law (dentists refusing to treat patients because of a fixed budget, introduction of prepayment methods in hospital etc.). Evaluation by the students at the end of the course revealed that PBL is well accepted in social medicine. Students rated learning success, relevance of the subject compared to other disciplines and the ability to transfer the acquired knowledge into medical practice well above the traditional courses. Besides lectures, practical courses and seminars, PBL should therefore be used as a standard method of learning in undergraduate medical education.     

Sleep architecture in a canine model of obstructive sleep apnea

Obstructive sleep apnea (OSA) causes recurrent sleep disruption that is thought to contribute to excessive daytime sleepiness in patients with this disorder. The purpose of this study was to determine the specific effects of OSA on overall sleep architecture in a canine model of OSA. The advantage of this model is that sleep during long-term OSA can be compared to both normal sleep before OSA and recovery sleep after OSA. Studies were performed in four dogs in which sleep-wake state was monitored continuously by a computer that received telemetered EEG and EMG signals. Whenever sleep was detected, the computer sent a signal to close a valve through which the dog breathed; when the dog awoke the occlusion was released. In each dog, data were analyzed from 4 consecutive nights in three phases: a control phase before induction of OSA, a phase during long-term OSA (mean = 85 days, apnea index = 59/hour), and a recovery phase after cessation of OSA. During recovery there was a significant increase in the amount of rapid-eye-movement (REM) sleep compared to the OSA phase (p < 0.01), as well as significant increases in sleep efficiency and decreases in wakefulness (p < 0.01), similar to that reported in OSA patients. The REM rebound during recovery, however, could not be attributed to overall REM deprivation since the amount of REM sleep during the OSA phase was not different from the control phase (p = 0.708). This finding suggests that REM rebound during recovery from OSA is not the result of an overall REM sleep deficit per se. Rather, repeated sleep disruption due to the effects of repetitive apneas and hypoxia may lead to an increased REM sleep drive that manifests itself as a REM sleep rebound during recovery sleep after OSA.     

Adult age differences in memory in relation to availability and accessibility of knowledge-based schemas.

Three experiments investigated whether, over adulthood, the use of schemas to process and remember new information increases (developmental shift hypothesis), decreases (production deficiency hypothesis) or remains constant (age-invariance hypothesis). Effects of schema access were studied by having young, middle-aged, and old music experts and nonexperts recall information that was relevant or irrelevant to music (Experiment 1) and by comparing young and old participants' memory for prose passages when they knew or did not know the subject of the passage (Experiments 2 and 3). In each case, schema access facilitated memory equally across age levels, supporting the age-invariance hypothesis and implying that the basic structures and operations of memory do not necessarily change with age. Possible limits on the independence of age and schema utilization were considered in relation to the conditions under which each of the two alternative hypotheses might hold. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Collagen fiber architecture of a cultured dermal tissue

Advances in tissue engineering have led to the development of artificially grown dermal tissues for use in burn and ulcer treatments. An example of such an engineered tissue is Dermagraft, which is grown using human neonatal fibroblasts on rectangular sheets of biodegradable mesh. Using small angle light scattering (SALS), we quantified the collagen fiber architecture of Dermagraft with the mesh scaffold contributions removed through the use of a structurally based optical model. Dermagraft collagen fibers were found to have a preferred direction nearly parallel to the long dimension of the kite-shaped mesh opening with small spatial variations over the mesh. This study demonstrated the utility of SALS as a rapid and inexpensive technique for the evaluation of gross collagen fiber architecture in engineered tissues.     

The architecture of intuition: Fluency and affect determine intuitive judgments of semantic and visual coherence and judgments of grammaticality in artificial grammar learning.

People can intuitively detect whether a word triad has a common remote associate (coherent) or does not have one (incoherent) before and independently of actually retrieving the common associate. The authors argue that semantic coherence increases the processing fluency for coherent triads and that this increased fluency triggers a brief and subtle positive affect, which is the experiential basis of these intuitions. In a series of 11 experiments with 3 different fluency manipulations (figure-ground contrast, repeated exposure, and subliminal visual priming) and 3 different affect inductions (short-timed facial feedback, subliminal facial priming, and affect-laden word triads), high fluency and positive affect independently and additively increased the probability that triads would be judged as coherent, irrespective of actual coherence. The authors could equalize and even reverse coherence judgments (i.e., incoherent triads were judged to be coherent more frequently than were coherent triads). When explicitly instructed, participants were unable to correct their judgments for the influence of affect, although they were aware of the manipulation. The impact of fluency and affect was also generalized to intuitions of visual coherence and intuitions of grammaticality in an artificial grammar learning paradigm. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Meaning as a factor in learning.

(This reprinted article originally appeared in the Journal of Educational Psychology, 1938, Vol 29, 419–430. The following abstract of the original article appeared in PA, Vol 13:797.) This is a selective review of the experiments on the effect of meaning on learning and retention. It is concluded that "the principles of contiguity, practice, the conditioned reflex, and the law of effect have receded from the foreground (as a result of studies of meaning as a factor in learning); and in their place have come such terms as insight, understanding, intelligence, organization, pattern, and the like. When (these terms) are more precisely defined they will lead us to not only a truer understanding of the learning process, but also to more practical results." (PsycINFO Database Record (c) 2010 APA, all rights reserved)