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PubMedDate not supplied

Pelvic pain: lessons from anatomy and physiology.

Pelvic pain is often a difficult differential diagnosis in the emergency department. For physiologic reasons, pain in the pelvis is difficult to localize to a specific organ, and pelvic peritonitis is hard to recognize. On the other hand, differences in types of pain can be very useful in arriving at a correct diagnosis. The clinician must learn to recognize superficial and deep somatic pain, and differentiate between various types of visceral pain which originate from inflammation, ischemia, or colic. A review of the anatomy and physiology of pelvic pain helps identify some of the problems as well as potential aids in approaching the patient with pelvic pain.

Adult↗
PubMed2000

Spectral tuning and the visual ecology of mantis shrimps.

The compound eyes of mantis shrimps (stomatopod crustaceans) include an unparalleled diversity of visual pigments and spectral receptor classes in retinas of each species. We compared the visual pigment and spectral receptor classes of 12 species of gonodactyloid stomatopods from a variety of photic environments, from intertidal to deep water (> 50 m), to learn how spectral tuning in the different photoreceptor types is modified within different photic environments. Results show that receptors of the peripheral photoreceptors, those outside the midband which are responsible for standard visual tasks such as spatial vision and motion detection, reveal the well-known pattern of decreasing lambdamax with increasing depth. Receptors of midband rows 5 and 6, which are specialized for polarization vision, are similar in all species, having visual lambdamax-values near 500nm, independent of depth. Finally, the spectral receptors of midband rows 1 to 4 are tuned for maximum coverage of the spectrum of irradiance available in the habitat of each species. The quality of the visual worlds experienced by each species we studied must vary considerably, but all appear to exploit the full capabilities offered by their complex visual systems.

Adaptation, Physiological↗
PubMed2004

Observations of veterinary medicine students' approaches to study in pre-clinical years.

RATIONALE FOR THIS STUDY: This study has two purposes. The first is to explore an instrument of evaluation of the approaches to study (deep, strategic, and surface) adopted by students in the pre-clinical years of their veterinary degree program. The second is to examine relationships between these approaches and a broad range of further factors deemed relevant to the veterinary medicine context. We envisage that a greater knowledge of how these students learn will aid curriculum reform in a way that will enrich the learning experience of veterinary students. METHODOLOGY: A questionnaire consisting of the 52-question Approaches to Study Inventory (ASI) and an additional 49 questions relating mainly to teaching, assessment, and study skills was distributed to 215 veterinary medicine (MVB) students in their pre-clinical years of study. Factor analysis was used to ensure that the ASI section of the questionnaire maintained previously reported structure. The internal reliability of the approaches measured was tested using Cronbach alpha analysis. The approaches were described as frequency distributions. Associations between the parameters (deep, strategic, and surface) and 49 additional context-specific factors were investigated using loglinear analysis. RESULTS: (1) Factor analysis revealed that the integrity and structure of the instrument in this context was generally comparable to previous studies. (2) The impact of a high workload was evident in the surface approach, with fear of failure becoming a strong motivating factor and syllabus boundness a widely used strategy. (3) Associations made between the approaches and 49 context-specific factors showed strong associations between both workload and lack of prior knowledge with the surface approach. (4) Grades were associated positively with both the deep and strategic approaches but negatively with the surface approach. (5) A range of learning and study skills were associated positively with the deep and strategic approaches and negatively with the surface approach. CONCLUSION: The ASI proved to be a reliable and insightful instrument, highlighting specific surface learning tendencies present in the group as well as a deep learning approach, the pattern of which deviates from previous studies on this subject. This study also confirms the value of some teaching practices as a means of supporting deep learning and perhaps challenging surface learning strategies. The prevalent perception of a high workload is notable, as is its positive association with surface learning.

Adolescent↗
PubMed2002

Pallidal stimulation for parkinsonism: improved brain activation during sequence learning.

We used (15)O-labeled water and positron emission tomography to assess the effect of deep brain stimulation of the internal globus pallidus on motor sequence learning in Parkinson's disease. Seven right-handed patients were scanned on and off stimulation while they were performing a motor sequence learning task and a kinematically matched motor execution reference task. The scans were performed after a 12-hour medication washout. Stimulation parameters were adjusted for maximal motor improvement; experimental task parameters were held constant across stimulation conditions. Internal globus pallidus stimulation improved motor ratings by 37% (p < 0.01). During the sequence learning task, stimulation improved performance as measured by several correct anticipatory movements (p < 0.01) and by verbal report (p < 0.001). Concurrent positron emission tomography imaging during learning demonstrated significant (p < 0.01) increases in brain activation with stimulation in the left dorsolateral prefrontal cortex, bilaterally in premotor cortex, and in posterior parietal and occipital association areas. Stimulation did not affect the activity of these regions during the performance of the motor execution reference task. These findings suggest that internal globus pallidus deep brain stimulation can enhance the activity of prefrontal cortico-striato-pallidothalamic loops and related transcortical pathways. Improved sequence learning with stimulation may be directly related to these functional changes.

Adult↗
PubMed1999

The effects of age on the neural correlates of episodic encoding.

Young and old adults underwent positron emission tomographic scans while encoding pictures of objects and words using three encoding strategies: deep processing (a semantic living/nonliving judgement), shallow processing (size judgement) and intentional learning. Picture memory exceeded word memory in both young and old groups, and there was an age-related decrement only in word recognition. During the encoding tasks three brain activity patterns were found that differentiated stimulus type and the different encoding strategies. The stimulus-specific pattern was characterized by greater activity in extrastriate and medial temporal cortices during picture encoding, and greater activity in left prefrontal and temporal cortices during encoding of words. The older adults showed this pattern to a significantly lesser degree. A pattern distinguishing deep processing from intentional learning of words and pictures was identified, characterized mainly by differences in prefrontal cortex, and this pattern also was of significantly lesser magnitude in the old group. A final pattern identified areas with increased activity during deep processing and intentional learning of pictures, including left prefrontal and bilateral medial temporal regions. There was no group difference in this pattern. These results indicate age-related dysfunction in several encoding networks, with sparing of one specifically involved in more elaborate encoding of pictures. These age-related changes appear to affect verbal memory more than picture memory.

Adult↗
PubMed2005

Lectures in problem-based learning--why, when and how? An example of interactive lecturing that stimulates meaningful learning.

Even though opinions differ as to whether lecturing is compatible with problem-based learning (PBL) or not, lectures are still a common form of instruction in PBL curricula. This paper discusses the lecture in the framework of theories of learning in general and the medical problem-based learning tradition in particular. An example of how theories of learning can be implemented in the lecture hall is presented. Theories that underpin PBL as an educational philosophy rather than as a method of instruction are reviewed. A lecture form, organized in introductory, in depth and application lectures, that responds to important factors for stimulating deep processing of knowledge and meaningful learning is discussed. Examples of and practical points about how to renew and restructure lectures in a way that counteracts surface approaches to learning, teacher centering and student passivity are presented. We argue that, with proper awareness of possible drawbacks of the large format, lectures can be used as valuable tools for learning also in a PBL curriculum.

Education, Medical↗
PubMed1988

Role of compression modalities in a prophylactic program for deep vein thrombosis.

During the past decade, we have learned a great deal about the etiology, pathogenesis, diagnosis, and treatment of thromboembolic disease. Subcutaneous heparin has emerged as a major deterrent worldwide for thrombosis prevention but is associated with the potential risk of bleeding and cannot be used in certain patient situations. External compression modalities have emerged as major alternate forms of prophylaxis. We have learned that these devices stimulate the fibrinolytic system, prevent stasis and the endothelial injury that can accompany extreme venous distention. Since they are not associated with bleeding or other serious complications, they are attractive methods for most surgeons, including those performing delicate or complex surgical procedures. Independent studies worldwide have demonstrated their effectiveness in reducing deep vein thrombosis, as recognized by the NIH Consensus Development Panel, and the evidence is compelling that DVT efficacy is a valid marker for PE efficacy. Since these devices reduce the incidence of deep vein thrombosis, they almost certainly must prevent pulmonary emboli; however, a properly designed protocol should be conducted to validate these assumptions. Evidence suggests that full-leg sequential compression is superior to calf compression, but further study is necessary. We believe that a hospital-wide plan, including risk-factor assessment and application of clinical management guidelines, including all available modalities, is important to provide the maximum protection of patients with the lowest risk of side effects. Such a program has been very successful in our community.

Clothing↗
PubMed2005

Entrepreneurship in continuing dental education: a dental school perspective.

The definition of continuing dental education is presented, along with its benefits to the profession. The preeminence of dental schools in providing lifelong learning opportunities and freedom from commercial involvement that existed even twenty years ago has changed. Less than a quarter of CE takes place in school, and the focus there is increasingly on material with deep scientific background and hands-on learning. The newest innovations and those with the greatest commercial potential are taught elsewhere. Proposed changes in the ADA CERP standards would take on a "purist" approach that could place dental schools at a severe disadvantage while allowing "for profit" institutes to flourish and thus further undermine the role dental schools can play in providing quality professional development experiences.

American Dental Association↗
PubMedDate not supplied

Stimulus generalization of conditioned eyelid responses produced without cerebellar cortex: implications for plasticity in the cerebellar nuclei.

In Pavlovian eyelid conditioning and adaptation of the vestibulo-ocular reflex, cerebellar cortex lesions fail to completely abolish previously acquired learning, indicating an additional site of plasticity in the deep cerebellar or vestibular nucleus. Three forms of plasticity are known to occur in the deep cerebellar nuclei: formation of new synapses, plasticity at existing synapses, and changes in intrinsic excitability. Only a cell-wide increase in excitability predicts that learning should generalize broadly from a training stimulus to other stimuli capable of supporting learning, whereas the alternatives predict that learning should be relatively specific to the training stimulus. Here we show that deep nucleus plasticity, as assessed by conditioned eyelid responses produced without input from the cerebellar cortex, is relatively specific to the training conditioned stimulus (CS). We trained rabbits to a tone or light CS with periorbital stimulation as the unconditioned stimulus (US), and pharmacologically disconnected the cerebellar cortex during a posttraining generalization test. The short-latency conditioned responses unmasked by this treatment showed strong decrement along the dimension of auditory frequency and did not generalize across stimulus modalities. These results cannot be explained solely by a cell-wide increase in the excitability of deep nucleus neurons, and imply that an input-specific mechanism in the deep cerebellar nucleus operates as well.

Acoustic Stimulation↗
PubMed2026

A framework for delivering real-time, instrument-relative navigation in transoral robotic surgery.

Transoral robotic surgery (TORS) is a minimally invasive, inside-out technique that, compared with traditional open approaches, provides fewer post-operative complications, shorter hospital stays, and improved survival for early-stage head and neck cancer. However, TORS is limited by its steep learning curve and poor visualization of deep tumor margins. This randomized crossover study evaluated a surgical navigation system's potential to enhance accuracy and user experience with real-time, instrument-relative feedback. Seven Teflon beads (d&#x2009;=&#x2009;2.381&#xa0;mm) were embedded at the tongue base of a porcine pharynx-and-larynx model. Tongue blade compression and retraction were applied to the model to mimic intraoperative tissue deformation, reproducing the anatomical shifts that occur relative to preoperative imaging. Eight participants used the da Vinci Surgical system to localize the beads by placing pins under two conditions: (a) preoperative computed tomography with no navigation; (b) model-based visual navigation with quantitative instrument-to-target metrics. Surgical accuracy was determined by calculating the target localization error (TLE, pin-to-bead Euclidean distance) and the angular error (AE, pin axis trajectory to bead). Accounting for training level and bead depth, surgical navigation reduced TLE by 5.44&#xa0;mm (95% CI, 4.02-6.86&#xa0;mm; p&#x2009;=&#x2009;2.00e-11) and AE by 8.47 degrees (95% CI, 6.21-10.72 degrees; p&#x2009;=&#x2009;5.17e-11). Impressions of the system were generally favorable using a 5-point Likert survey and task duration (p&#x2009;=&#x2009;0.26) or cognitive workload via the NASA-Task Load Index (p&#x2009;=&#x2009;0.22) were not significantly affected. The navigation system demonstrated translational promise, offering improved target localization accuracy and more consistent performance across experience levels, two critical determinants of surgical quality in TORS.

Robotic Surgical Procedures↗
PubMed1986

Pulmonary embolism. Guide to diagnosis, treatment, and prevention.

While more remains to be learned about the natural history of deep vein thrombosis and pulmonary embolism, better information is now available on which to base decisions about diagnosis and treatment. Several retrospective and prospective studies have placed the value of lung scanning, venography, and pulmonary angiography in better perspective. Newer diagnostic techniques for deep vein thrombosis, such as 125I-labeled fibrinogen scanning and impedance plethysmography, are valuable and should be more widely used. Other diagnostic techniques for pulmonary embolism, such as computed tomography and nuclear magnetic resonance imaging, may be of value but are still untested. More effective therapies are now available. Moderate-dose subcutaneous heparin and lower-dose warfarin for long-term therapy of deep vein thrombosis are attractive alternatives to standard warfarin therapy. Thrombolytic therapy has not replaced standard intravenous heparin therapy, although it should be considered in treatment of a massive pulmonary embolus. Perhaps most important, prevention of deep vein thrombosis in most patients at high risk is possible with minidose heparin therapy or intermittent pneumatic compression. One of these methods of prophylaxis should be used in all high-risk patients as the only current effective way to decrease the mortality of pulmonary embolism.

Angiography↗
PubMed2006

Multi-dimensional profiling of medical students' cognitive models about learning.

INTRODUCTION: In current constructivist paradigms, learners' previous subject-matter knowledge, or cognitive models, provide the foundations for the construction of new knowledge. Learners' cognitive models about learning also mediate students' capacities to learn in their chosen topics of study. The diverse backgrounds of students entering medicine suggest that they might come to medical studies equipped with a wide variety of cognitive models about learning. Some current theories tend to reduce students' cognitions about learning to parsimonious representations, such as surface-deep approaches or mastery-performance goals. It is possible that such reduced representations underrepresent, or misrepresent, the complexity of students' cognitive models about learning. Good quality teaching needs to take account of learners' cognitive models, not just about subject matter, but also about learning. This study investigated the diversity and complexity of medical students' cognitive models about learning. METHODS: A total of 7 graduate entry, clinical-year medical students volunteered for in-depth interviews about learning. NUD*IST text analysis software and correspondence analysis were employed to identify dimensions and to profile students' responses. RESULTS: The correspondence analysis identified a significant 4-dimensional solution that illustrates the contributions of multiple variables to students' cognitive models about learning. Individual profiles highlight diversity between participants. DISCUSSION: This study provides evidence that students' cognitive models about learning are complex and highly differentiated. Representations of what students know about learning need to take account of such complexity in order to inform instructional practice more adequately.

Cognition↗
PubMed2004

Examining the multidimensionality of approaches to learning through the development of a revised version of the Learning Process Questionnaire.

AIM: This study aimed to produce a revised two-factor version of the Learning Process Questionnaire (R-LPQ-2F) with deep and surface approach scales, measured by a reasonably small number of items, suitable for use by teachers in secondary schools to evaluate the learning approaches of their students. METHOD: A set of 41 items was derived, with modification, from the original version of the LPQ and from items used to develop the revised version of the SPQ. These items were tested using reliability procedures and confirmatory factor analysis and items were deleted until scales were of a suitable length and confirmatory factor analysis indicated a good fit to the intended two-factor structure. SAMPLE: The sample consisted of 841 students from 20 secondary schools in Hong Kong. RESULTS: The final two-factor version of the questionnaire had good Cronbach alpha values and reasonable goodness-of-fit values for the confirmatory analysis. There was a much better fit, though, to a hierarchical structure with motive and strategy subscales for each approach, each of which, in turn, had two subcomponents. CONCLUSION: Approaches to learning have a hierarchical dimensionality with motive and strategy elements. Each motive and strategy element is itself multidimensional. The results are used to question the conventional approach to the testing and acceptance of instruments, which place sole reliance upon reliability tests. The use of confirmatory factor analysis is recommended as a routine procedure in the development and testing of instruments.

Adult↗
PubMed2002

Measuring self-reported studying and learning for university students: linking attitudes and behaviours on the same scale.

BACKGROUND: The relationships between self-reported Approaches to Studying and Self-concept, Self-capability and Studying and Learning Behaviour are usually studied by measuring the variables separately (using factor analysis and Cronbach Alphas) and then using various correlation techniques (such as multiple regression and path analysis). This procedure has measurement problems and is called into question. AIMS: To create a single scale of Studying and Learning using a model with subsets of ordered stem-items based on a Deep Approach, a Surface Approach and a Strategic Approach, integrated with three self-reported aspects (an Ideal Self-view, a Capability Self-view and a Studying and Learning Behaviour Self-view). SAMPLES: The stem-item sample was 33, all answered in three aspects, that produced an effective item sample of 99. The person convenience sample was 431 students in education (1(st) to 4(th) year) at an Australian university during 2000. METHOD: The latest Rasch Unidimensional Measurement Model Computer Program (Andrich, Lyne, Sheridan, & Luo, 2000) was used to analyse the data and create a single scale of Studying and Learning. RESULTS: Altogether 77 items fitted a Rasch Measurement Model and formed a scale in which the 'difficulties' of the items were ordered from 'easy' to 'hard' and the student measures of Studying and Learning were ordered from 'low' to 'high'. The proportion of observed student variance considered true was 0.96. The response categories were answered consistently and logically and the results supported many, but not all, the conceptualised ordering of the subscales. Students found it 'easy' to report a high Ideal Self-view, 'much harder' to report a high Capability Self-view, and 'harder still' to report a high Studying and Learning Behaviour for the stem-items, in accordance with the model, where items fit the measurement model. The Ideal Self-view Surface Approach items provided the most non-fit to the model. CONCLUSION: This method was highly successful in producing a single scale of Studying and Learning from self-reported Self-concepts, Self-capabilities, and Studying and Learning Behaviours, based on a Deep Approach, a Surface Approach and a Strategic Approach.

Achievement↗
PubMed2001

Impairment of eyeblink classical conditioning in progressive supranuclear palsy.

In a previous study we showed that learning in eyeblink classical conditioning (EBCC) is normal in Parkinson's disease (PD) and that the serial reaction time task (SRTT) is only marginally impaired. Since pathological lesions are more widespread in the atypical parkinsonian disorder of progressive supranuclear palsy (PSP) than in PD, we hypothesized that PSP patients may show more profound deficits in the EBCC and SRTT learning tasks. We therefore investigated EBCC with a delay and two trace paradigms, an SRTT and the California Verbal Learning Test (CVLT) in eight patients with PSP and an age-matched control group. In all EBCC paradigms, we found a significant difference between groups with no significant learning in PSP patients. In the SRTT, implicit learning may have been impaired, but verbal and manual sequence recall were only marginally impaired. Verbal memory was significantly worse in PSP patients than in the control group. Our study shows a dissociated pattern of learning abilities in PSP, where the EBCC as a measure of implicit learning is impaired, the explicit sequence detection in the SRTT is relatively preserved, and the verbal memory impaired. We hypothesize that the PSP patients' deficits in EBCC learning may be due to lesions of deep cerebellar nuclei. There may be a clinical role for EBCC in distinguishing PD and PSP patients.

Aged↗
PubMed2004

AutoTutor: a tutor with dialogue in natural language.

AutoTutor is a learning environment that tutors students by holding a conversation in natural language. AutoTutor has been developed for Newtonian qualitative physics and computer literacy. Its design was inspired by explanation-based constructivist theories of learning, intelligent tutoring systems that adaptively respond to student knowledge, and empirical research on dialogue patterns in tutorial discourse. AutoTutor presents challenging problems (formulated as questions) from a curriculum script and then engages in mixed initiative dialogue that guides the student in building an answer. It provides the student with positive, neutral, or negative feedback on the student's typed responses, pumps the student for more information, prompts the student to fill in missing words, gives hints, fills in missing information with assertions, identifies and corrects erroneous ideas, answers the student's questions, and summarizes answers. AutoTutor has produced learning gains of approximately .70 sigma for deep levels of comprehension.

Algorithms↗
PubMed1996

Neural substrates of discriminative avoidance learning and classical eyeblink conditioning in rabbits: a double dissociation.

In a previous study, lesions of the deep cerebellar nuclei blocked classical eyeblink conditioning, but did not impair discriminative avoidance learning in rabbits. Here, was also found previously, lesions of the anterior and medial dorsal thalamic nuclei severely impaired discriminative avoidance learning. However, these lesions had no impact on discriminative eyeblink conditioning or reversal learning. These results complete the demonstration of a double dissociation, indicating distinct neural substrates for the acquisition of these learned behaviors. It is proposed that the two learning circuits identified by these studies mediate, respectively, acquisition of specific adaptive reflexes and whole-body, voluntary goal-directed movements.

Animals↗