PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “GENERALIZATION LEARNING”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 667 records · Page 37Linked to original sources
PubMed2006

Treating recurrence after a totally extraperitoneal approach.

BACKGROUND: One of today's most highly regarded procedures for treating inguinal hernia is the totally extraperitoneal approach (TEP), but it can on occasion lead to recurrence. This is commonly managed with an open repair, a transabdominal preperitoneal procedure (TAPP), or another TEP. We report here on our years of experience with the latter. METHODS: The endeavor to a secondary TEP is much the same as to a primary one, but certain differences are encountered as the operation proceeds. For example, many anatomical landmarks found in a first TEP cannot be seen in a second. There can also be a diminished amount of working space, and this occasionally leads to an open conversion. RESULTS: From September 1991 to September 2005, we repaired 1,526 hernias in 1,156 male patients, using the TEP in every case. Of these, 21 were TEPs after a previous TEP. In 3 cases, the space could not be opened, and they were converted to the open Lichtenstein. One patient had peritoneal tears that led to conversion and another had conversion because of excessive bleeding. There were no complications, no bladder or bowel injuries, no transfusions, no preperitoneal hematomas, and no fatalities. All patients were discharged the same day. CONCLUSIONS: A secondary TEP, open repair, and TAPP are alternative solutions to the problem of recurrence after TEP. However, any TEP involves a very prolonged learning curve for general surgeons, since they must learn the anatomy as well as the procedure, both at the same time. This is doubly true for the TEP after a previous TEP.

Hernia, Inguinal↗
PubMed1992

Imagery mnemonics and memory remediation.

This paper evaluates the claim that imagery mnemonic techniques are useful in remediation of memory disorders in brain-damaged patients. Clinical research has confirmed that such techniques can lead to improved performance on formal testing in a number of neurologic disease populations and following lesions of either the left or right hemisphere. However, those patients with more severe forms of amnesia and those with medial or bilateral damage do not improve unless the learning task is highly structured. Even among patients who show improvement on formal testing, there is little evidence that they maintain the use of these techniques in similar learning tasks or generalize the use to new learning situations. Imagery mnemonics also appear to be of little practical value in the daily activities that are of most concern to brain-damaged patients themselves. The effectiveness of imagery mnemonics appears to depend upon the patients' motivation and insight rather than upon their intelligence or educational level. Instead of training patients in specific mnemonic techniques, clinicians should promote the development of "meta-cognitive" skills and the acquisition of knowledge about domains of practical significance.

Humans↗
PubMed1996

Dynamics of time discrimination: II. The effects of multiple impulses.

According to a diffusion generalization model, time discrimination is determined by the frequency and recency of preceding intervals of time. A procedure for studying rapid timing was used to investigate whether pigeons' wait-time responses were sensitive to these factors. In Experiment 1 the number (two or eight) and spacing (consecutive or far apart) of 5-s interfood intervals (called impulses) intercalated in a series of 15-s interfood intervals (nonimpulses) were studied. Experiment 2 was identical to the first but the interfood intervals were increased by a factor of three. Overall, impulses shortened wait times in the next interfood interval. However, several impulses occurring in succession extended the localized effect of an impulse: Wait times following a set of eight-close impulses were slow to recover to preimpulse levels. The results show that linear waiting is only an approximation to the dynamic process, and a process that is sensitive to events in an animal's remote past, such as the diffusion generalization model, provides a better account of rapid timing effects.

Animals↗
PubMed1999

Sensitization to apomorphine in pigeons is due to conditioning, subject to generalization but resistant to extinction.

Apomorphine (Apo) administration induces a persistent bout of pecking in pigeons and other birds. Repeated injections of Apo in pigeons lead to sensitization, i.e. the pecking response to a particular dose increases up to a dose-dependent asymptotic level. It is also known that Apo-induced pecking can be classically conditioned to the cage environment where the animals experience the effect of the drug. Here we address the question of whether, and to what extent, the sensitization effect arises as a consequence of a conditioning or of a pharmacological process. An extinction experiment demonstrated that an extinction procedure supposed to be effective in inhibiting the conditioned pecking response was not effective in suppressing the sensitization to Apo, thus casting provisional doubt on the conditioning hypothesis. However, a conditioning experiment demonstrated that the sensitization effect undoubtedly involved an important component of conditioning to an experimental cage environment, but also suggested that there was an additional component possibly not due to learning. A generalization experiment, however, showed that this second component was very probably due to a stimulus generalization effect deriving from conditioning to the home cage, suggesting that learning can account for most, if not all, of the increase in Apo-induced pecking and that an exclusively pharmacological sensitization process plays, at best, a minor role. The apparent contrast between the results of the first experiment, indicating that the sensitization is not affected by inhibitory conditioning, and the results of the last two experiments, suggesting that the sensitization is due to excitatory conditioning, can be resolved by assuming that Apo induces a drug-state-dependent conditioning. These results are related to findings and arguments concerning the sensitization to psychostimulant drugs in mammals.

Animals↗
PubMed2003

General concepts in full scale simulation: getting started.

UNLABELLED: Over the past decade, medical simulation has developed to a point where it now is poised to become ubiquitous in teaching curricula. Despite this experience, there is little up-to-date information to help new instructors and operators learn the general principles of simulation. The purpose of this article is to provide prospective simulation instructors with basic concepts and a practical approach to patient simulation. The main focus is on full-scale or high fidelity simulation. The article is intended to (a). prepare instructors to use full-scale simulation to educate students; (b). teach some of the complexities and terminology of simulation; (c). prepare for and complement the curriculum of a formal instructor course; and (d). teach the basic elements required to run a successful simulation. This article should be used as an adjunct to practical experience gained from using simulation units. IMPLICATIONS: Medical simulation replicates normal and abnormal physiology and pathology. It is a tool that is intended to increase experiential learning. Establishing a functional and useful simulation program involves many factors. This paper presents a detailed introduction to the concepts and methodology of simulation in medicine.

Anesthesiology↗
PubMed1999

Perceptual learning in motion discrimination that generalizes across motion directions.

When human subjects discriminate motion directions of two visual stimuli, their discrimination improves with practice. This improved performance has been found to be specific to the practiced directions and does not transfer to new motion directions. Indeed, such stimulus-specific learning has become a trademark finding in almost all perceptual learning studies and has been used to infer the loci of learning in the brain. For example, learning in motion discrimination has been inferred to occur in the visual area MT (medial temporal cortex) of primates, where neurons are selectively tuned to motion directions. However, such motion discrimination task is extremely difficult, as is typical of most perceptual learning tasks. When the difficulty is moderately reduced, learning transfers to new motion directions. This result challenges the idea of using simple visual stimuli to infer the locus of learning in low-level visual processes and suggests that higher-level processing is essential even in "simple" perceptual learning tasks.

Humans↗
PubMed2005

Self directed learning and continuing medical education.

Self directed learning (SDL) for continuing medical education (CME) is the most effective approach for improving physician performance and patient care outcomes. Self directed learning is an essential basis for CME. However, instructor directed programs--particularly on-site conferences--remain the most popular method for acquiring CME. This article briefly examines the evolution of SDL and its importance in lifelong learning for general practice. The challenge for CME providers is to facilitate SDL while taking general practitioners' views and preferences into consideration.

Adult↗
PubMed1993

On the role of the hippocampus in learning and memory in the rat.

An overview of lesion experiments concerned with the involvement of the hippocampus in learning and memory in the rat is presented. Multiple injections of small amounts of ibotenic acid were used to selectively remove the hippocampus (dentate gyrus, hilar cells, CA1-CA3 pyramidal cells). Similar selective, axon-sparing ibotenate lesions of hippocampus were used in a series of learning and memory experiments employing tasks that are thought to be important in hippocampal function. The performance of rats with the hippocampus removed was compared with that of control animals in the acquisition and retention of spatial versus nonspatial information, forgetting of spatial and nonspatial information, contextual learning, recognition memory and concurrent discrimination learning, and complex representational learning (conditional discrimination and negative patterning learning). The general finding that rats without a hippocampus were impaired on those tasks that required the utilization of spatial and contextual information stands in contrast with the spared performance that was found in learning about and handling (even complex) nonspatial information. Rather than support for views that emphasize a role for the hippocampus in specific memory processes (working memory, declarative memory, temporary memory buffer, configural learning), the present results are more compatible with the idea that the hippocampus plays an especially important role in processing and remembering spatial and contextual information. The limited data that are available using more selective lesions of related hippocampal formation structures (entorhinal cortex, subiculum) suggest that these structures also make important contributions to learning and memory, and that some of these contributions may be different from those made by the hippocampus.

Animals↗
PubMed1994

Relationships between measures of auditory verbal learning and executive functioning.

Relationships between performance on the California Verbal Learning Test (CVLT) and executive abilities were examined. In a sample of 115 neurological cases principal components factor analysis produced five theoretically and clinically meaningful CVLT factors. The five CVLT factors reflected general verbal learning (CVLT1), response discrimination (CVLT2), a proactive interference effect or "working memory" (CVLT3), serial learning strategy (CVLT4), and a retroactive interference effect (CVLT5). Canonical correlation between executive function measures and the five CVLT factor scores yielded one significant canonical variable accounting for 29 percent of the variance in the data. Two CVLT factors (CVLT1 and CVLT3), the Trail Making Test Part B, and Digit Span were significantly correlated with the canonical variate. Higher levels of memory performance were associated with better attention and mental tracking. Based on the present findings, attentional aspects of executive abilities appear to play a role in learning and working memory. Other aspects of executive abilities (abstraction, problem-solving, planning) appear to have minimal relationships with memory processes.

Adolescent↗
PubMed1988

Discriminative stimulus control by the anxiogenic beta-carboline FG 7142: generalization to a physiological stressor.

Drug discrimination was employed to investigate the similarities between FG 7142-induced anxiogenesis and the stress produced by exposure to either a novel environment or to footshock. Eight rats were trained to discriminate between the stimulus properties of the beta-carboline FG 7142 (5.0 mg/kg) and its vehicle in a two-lever, food motivated operant task. Once trained, decreasing doses of FG 7142 produced fewer FG 7142-appropriate responses and the dose-response relationship yielded an ED50 of 1.45 mg/kg. Rats were subsequently subjected to two physiological/environmental stressors, footshock and novelty, and then tested in the discriminative paradigm. Exposure to novelty resulted in partial FG 7142-appropriate responding, whereas footshock sessions produced responding predominately on the FG 7142-appropriate lever. This is the first report of stimulus control by FG 7142 and it is likely that the interoceptive cue state produced by this compound is anxiogenic in nature, as reported to occur in man. The anxiogenic nature of the FG 7142 discriminative stimulus is supported by the generalization of FG 7142 to the state produced following stressful environmental manipulation.

Animals↗
PubMed1975

Stimulus generalization and anxiety in schizophrenic and normal subjects.

Sixty schizophrenics and 60 normal subjects were compared on a test of stimulus generalization. The generalization stimuli were lines differing in length. Both schizophrenics and normals were divided into two groups (30 subjects each) and trained either on a short line or on a long line. In addition to the generalization stimuli, subjects were presented with an irrelevant stimulus (circle). Although there was a significant difference between the generalization gradients of the groups, this difference was limited to generalization stimuli away from the negative training stimulus. The concept of peak shift was invoked to interpret these data. That the groups did not respond to the irrelevant stimulus is inconsistent with interference theory and gives some support to the differentiation between conceptual overinclusion and perceptual overinclusion. The relationship between stimulus generalization and scores on the Manifest Anxiety Scale was inconsistent.

Anxiety↗
PubMedDate not supplied

Explanation and generalization in young children's strategy learning.

Children often learn new problem-solving strategies by observing examples of other people's problem-solving. When children learn a new strategy through observation and also explain the new strategy to themselves, they generalize the strategy more widely than children who learn a new strategy but do not explain. We tested three hypothesized mechanisms through which explanations might facilitate strategy generalization: more accurate recall of the new strategy's procedures; increased selection of the new strategy over competing strategies; or more effective management of the new strategy's goal structure. Findings supported the third mechanism: Explanations facilitated generalization through the creation of novel goal structures that enabled children to persist in use of the new strategy despite potential interference from competing strategies. The facilitative effect of explanation did vary with children's age and did not vary between explanations children created by themselves versus explanations they learned from the experimenter.

Analysis of Variance↗
PubMed2004

Learning with computerized guidelines in general practice?: A randomized controlled trial.

BACKGROUND: Evidence-based guidelines are seen as an important instrument to transfer scientifically generated knowledge into daily clinical practice and to ensure high standards of clinical care. Despite wide promulgation, clinical guidelines so far have a limited impact on individual professional learning and on changing daily medical practice. OBJECTIVES: Our aims were (i) to study a potential knowledge increase among German GPs after implementation of web- and evidence-based guidelines and (ii) to identify and analyse potential barriers to individual professional learning with computerized guidelines. METHODS: A prospective, randomized controlled trial was conducted including 72 GPs (21% female, 79% male). The intervention group (n = 38) had access to clinical guidelines via the Internet or CD-ROM, the control group had not (n = 34). Both groups received a standardized two-part questionnaire. An increase of knowledge was measured with 25 multiple choice questions related to four different medical topics. In addition, reasons for using or not using computerized guidelines were analysed after access to guidelines was open to all participating physicians. RESULTS: There was no significant knowledge increase in the intervention group (P = 0.69). Twenty-two (58%) GPs of the intervention group had used the guidelines. Unspecified curiosity (76%) and a specific medical question (38%) were predominant motives for usage among physicians who had used the guidelines. Among 'non-users', 78% stated 'lack of time' as the main reason for not using guidelines. CONCLUSION: An efficient knowledge transfer through computerized guidelines was not achieved. Usage, individual learning and potential implementation depend on adequate incentives and pragmatic aspects of clinical practice: easy and quick access.

Adult↗
PubMed1999

Community-based clinical education at the University of Birmingham Medical School.

Throughout the United Kingdom, medical schools have begun to make significant changes in the content and delivery of their undergraduate curricula in response to a number of social and educational forces. In particular, many schools have begun to focus increasingly on community-based education. This and other changes mirror developments that have taken place in other countries and in the context of other health care systems, with such forerunners as Harvard, Maastricht, and McMaster having had a fundamental influence. In this article, the authors describe the forces for curricular change in the United Kingdom and the specific recommendations for change made by the General Medical Council. They then discuss in detail the new curriculum at the University of Birmingham medical school, focusing in particular on a community medicine module, where students spend ten days per academic year learning in general medical practices in and around the city of Birmingham.

Clinical Clerkship↗
PubMed2005

Segregation between acquisition and long-term memory in sensorimotor learning.

It is widely accepted that learning first involves generating new memories and then consolidating them into long-term memory. Thus learning is generally viewed as a single continuous process with two sequential stages; acquisition and consolidation. Here, we tested an alternative hypothesis proposing that acquisition and consolidation take place, at least partly, in parallel. Human subjects learned two visuomotor tasks. One task required moving a cursor under visuomotor rotation and the other required arbitrary association of colour to direction of movement. Subjects learned the two tasks in sequence, and were tested for acquisition of the second immediately after learning the first, and for retention of the first on the following day. The results show that learning one task led to proactive interference to acquisition of the second. However, this interference was not accompanied by retroactive interference to consolidation of the first task, indicating that acquisition and consolidation can be uncoupled.

Adult↗
PubMed2000

Approaches to learning spatial relationships in gross anatomy: perspective from wider principles of learning.

When students learn spatial relationships in gross anatomy, as in other areas of study, fundamentals should be learned first; otherwise confusion results. The fundamentals in gross anatomy are defined not in conceptual terms but by principles of visual perception. In particular, they derive from Gestalt principles such as collinearity and symmetry, which generally make learning and recognition of visual patterns easier. The collinearity (straight line formations) and symmetry in the body cavities are obvious when one studies the empty cavities, or body cavities with only a few symmetrical structures in place. These principles are, however, totally obscured if one starts one's study, as in traditional dissection, with the body cavities crammed full of a complex mass of interlocking organs. and their ducts, vessels, etc. Therefore, it is recommended that learning gross anatomy (especially of the body cavities) would be an easier exercise if it started with empty body cavities, then building up, with a careful sequence of prosections, to the more complex and realistic anatomy of the full cavities. This system of learning is perceptually preferable to traditional dissection. However, it needs to be enlivened in several ways, e.g., with respect to design principles evident in anatomical structure (especially for the musculoskeletal system), developmental processes, and sometimes by explicit reference to clinical relevance.

Anatomy↗