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PubMed1984

Process curriculum in nursing contrasted to product orientation.

In summary the major variations in these two conceptions of curriculum include definitions of curriculum and learning, sources of curriculum and instructional content, technical language and underlying these their basic orientations. Yet, the two share intents in the areas of curricular theory, structure, teaching, development, and evaluation. The significance of these differences lies very much on the shoulders of the users of these two conceptions. The selection of one over the other must be gauged against each user's educational priorities and orientation. Implementation of each depends on a full understanding of each model. Even if a strict adherence to one or the other is not pursued, the review of both helps immensely in clarifying the specific concepts and estimating the impact of each model. It is through comparison that the assets and liabilities of each will be identified.

Curriculum↗

PubMedDate not supplied

Leadership in academic medicine: reflections from administrative exile.

Physicians are drawn into diverse leadership roles in academic medicine, but little in our education and training prepares us for these responsibilities. Fortunately, there is growing convergence in the literature on the attributes of successful leaders for knowledge-based organisations. Top-performing leaders seem to be self-effacing team-builders who eschew rapid-cycle strategic planning and management trends, focusing instead on strategic and incremental changes that will gradually transform their organisations. Academic physicians and search committees often concentrate on personal achievement and intellectual or technical mastery in research and clinical care. In contrast, the literature on leadership suggests other-directed skills matter more, eg mentorship, learning and teaching competencies, and so-called emotional intelligence. As a corollary, teaching hospitals, universities, and professional colleges or societies are long-term organisations with a rich history. Leadership in such a context demands stewardship of tradition along with patient pursuit of changes required to ensure that the organisation evolves successfully.

Academic Medical Centers↗

PubMed1999

Incentive downshifts evoke search repertoires in rats.

Negative incentive contrast effects (NCEs) have typically been attributed to frustration or the decremental generalization of learned associations. The purpose of these experiments was to clarify the relation of NCEs to the repertoires of functional search behaviors evoked by incentive downshifts. Rats shifted from 32% to 4% sucrose-solution decreased consummatory responses but increased nose-down locomotion, orientation, location entries, and sampling of alternatives relative to unshifted controls. These changes in behavior were terminated or failed to occur under incentive upshifts. Furthermore, reward downshifts did not produce avoidance of the location of the shifted incentive. Increased search occurred whether or not alternative reward locations were available. Together the evidence suggests that NCEs are related to evoked search modes supporting a repertoire of functional behaviors related to finding food.

Animals↗

PubMed1999

[Correlations between brain SPECT and neuropsychology assessments in mild and moderate stages of Alzheimer's disease].

UNLABELLED: Thirty-four patients with a probable Alzheimer's Disease (AD) (mild AD = 16; moderate AD = 18) and 12 matched controls were evaluated using semiquantitative SPECT-99mTc-HMPAO and neuropsychological tests (CERAD). RESULTS: Both temporal hypoperfusion (p < 0.01) and memory tests (p < 0.001) made it possible to differentiate the controls from mild AD patients. In these patients, significant correlations (p < 0.05) were also found between: 1) delayed recall test/temporal hypoperfusion, 2) learning memory test/temporoparietal and frontal hypoperfusion and 3) visual constructive praxis/posterior temporal hypoperfusion. In contrast to mild AD, moderate AD patients showed higher temporal (p < 0.01) parietal and frontal (p < 0.05) hypoperfusion along with worsening of praxis (p < 0.001) and memory tests (p < 0.05). CONCLUSIONS: SPECT imaging and neuropsychology evaluation can distinguish controls from AD patients with mild an moderate grades of dementia, showing a strong correlation from the early stages of AD.

Aged↗

PubMed2006

The effects of category overlap on information-integration and rule-based category learning.

In three experiments, we investigated whether the amount of category overlap constrains the decision strategies used in category learning, and whether such constraints depend on the type of category structures used. Experiments 1 and 2 used a category-learning task requiring perceptual integration of information from multiple dimensions (an information-integration task) and Experiment 3 used a task requiring the application of an explicit strategy (a rule-based task). In the information-integration task, participants used perceptual-integration strategies at moderate levels of category overlap, but explicit strategies at extreme levels of overlap--even when such strategies were suboptimal. In contrast, in the rule-based task, participants used explicit strategies, regardless of the level of category overlap. These data are consistent with a multiple systems view of category learning, and suggest that categorization strategy depends on the type of task that is used, and on the degree to which each stimulus is probabilistically associated with the contrasting categories.

Adolescent↗

PubMed2002

Learning to recognize talkers from natural, sinewave, and reversed speech samples.

In 5 experiments, the authors investigated how listeners learn to recognize unfamiliar talkers and how experience with specific utterances generalizes to novel instances. Listeners were trained over several days to identify 10 talkers from natural, sinewave, or reversed speech sentences. The sinewave signals preserved phonetic and some suprasegmental properties while eliminating natural vocal quality. In contrast, the reversed speech signals preserved vocal quality while distorting temporally based phonetic properties. The training results indicate that listeners learned to identify talkers even from acoustic signals lacking natural vocal quality. Generalization performance varied across the different signals and depended on the salience of phonetic information. The results suggest similarities in the phonetic attributes underlying talker recognition and phonetic perception.

Female↗

PubMedDate not supplied

Nerve growth factor with insular cortical grafts induces recovery of learning and reestablishes graft choline acetyltransferase activity.

Rats showing disrupted taste aversion due to insular cortex (IC)-lesions received either IC-grafts with NGF, grafts without NGF, or NGF alone. An additional group served as lesioned controls. Only those animals that received IC-grafts with NGF recovered the ability to learn the conditioned taste aversion task, at 15 days post-graft. Choline acetyltransferase (ChAT) activity in the IC-grafts with, but not without NGF, was similar to the IC activity of unoperated controls. In contrast, glutamate decarboxylase activity was similar in all the groups. These findings suggest that IC-grafts associated with NGF induce recovery of learning abilities in IC-lesioned rats, which correlates with reestablishment of ChAT activity in the grafts at 15 days post-implantation.

Animals↗

PubMed1984

Defeat, learned submissiveness, and analgesia in mice: effect of genotype.

Defeat-induced unconditioned and conditioned behaviors of C57BL/6 and DBA/2 mice were assessed in a social-learning paradigm. Upon bites, mice of the DBA strain reacted with significantly more escape reactions, while C57 mice showed more immobility, crouch, and defensive sideways and upright postures. Clear genotype-dependent patterns were also evident from the conditioned responses recorded 24 h after defeat. DBA mice displayed more escape and defensive sideways and upright postures upon contact with a nonaggressive partner mouse; in contrast, C57 mice reacted with more immobility and crouch. With an increasing number of bites the sum of learned responses increased in C57 mice while it decreased in mice of the DBA strain. This decrement was paralleled by an increase in the analgesic response measured on the hot plate in defeated DBA mice. The possible role of endogenous opioids in the genotype-dependent interaction of defeat-induced learned submissiveness and analgesia is discussed.

Aggression↗

PubMed1998

Perceptual learning reflects external noise filtering and internal noise reduction through channel reweighting.

To investigate the nature of plasticity in the adult visual system, perceptual learning was measured in a peripheral orientation discrimination task with systematically varying amounts of external (environmental) noise. The signal contrasts required to achieve threshold were reduced by a factor or two or more after training at all levels of external noise. The strong quantitative regularities revealed by this novel paradigm ruled out changes in multiplicative internal noise, changes in transducer nonlinearites, and simple attentional tradeoffs. Instead, the regularities specify the mechanisms of perceptual learning at the behavioral level as a combination of external noise exclusion and stimulus enhancement via additive internal noise reduction. The findings also constrain the neural architecture of perceptual learning. Plasticity in the weights between basic visual channels and decision is sufficient to account for perceptual learning without requiring the retuning of visual mechanisms.

Adult↗

PubMed1999

Learning physiology through service.

A service-learning component has been successfully incorporated into an introductory physiology course at Wheaton College. In addition to regular course work, each of the 24 students spent 12 hours shadowing and assisting staff at Sturdy Memorial Hospital, Attleboro, MA, with 4 hours in the emergency room and 8 hours in two other departments. Every student kept a log of his or her observations, reactions, and learning in the field and wrote a paper on a pathophysiological condition encountered in the hospital. To compare and contrast the real hospital experience with a fictional one, the students also studied patients from the television show ER. Each week in lab, two students showed a short videotape of one particular patient and discussed the diagnosis, symptoms, treatments, and surgical procedures involved. Questionnaire evaluations indicated that this program is effective in helping students learn more physiology and exposing them to community service. Health workers and patients also agreed that providing social support to patients while shadowing and assisting hospital staff was a valuable service.

Educational Measurement↗

PubMed2005

Functional magnetic resonance imaging activity during the gradual acquisition and expression of paired-associate memory.

Recent neurophysiological findings from the monkey hippocampus showed dramatic changes in the firing rate of individual hippocampal cells as a function of learning new associations. To extend these findings to humans, we used blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to examine the patterns of brain activity during learning of an analogous associative task. We observed bilateral, monotonic increases in activity during learning not only in the hippocampus but also in the parahippocampal and right perirhinal cortices. In addition, activity related to simple novelty signals was observed throughout the medial temporal lobe (MTL) memory system and in several frontal regions. A contrasting pattern was observed in a frontoparietal network in which a high level of activity was sustained until the association was well learned, at which point the activity decreased to baseline. Thus, we found that associative learning in humans is accompanied by striking increases in BOLD fMRI activity throughout the MTL as well as in the cingulate cortex and frontal lobe, consistent with neurophysiological findings in the monkey hippocampus. The finding that both the hippocampus and surrounding MTL cortex exhibited similar associative learning and novelty signals argues strongly against the view that there is a clear division of labor in the MTL in which the hippocampus is essential for forming associations and the cortex is involved in novelty detection. A second experiment addressed a striking aspect of the data from the first experiment by demonstrating a substantial effect of baseline task difficulty on MTL activity capable of rendering mnemonic activity as either "positive" or "negative."

Adult↗

PubMed1994

Reduced hippocampal long-term potentiation and context-specific deficit in associative learning in mGluR1 mutant mice.

We generated a novel strain of mutant mouse with a deletion in the gene encoding metabotropic glutamate receptor 1 (mGluR1). Gross anatomy of the hippocampus, excitatory synaptic transmission, long-term depression, and short-term potentiation in the hippocampal CA1 region are all apparently normal in the mutant mice. In contrast, long-term potentiation (LTP) is substantially reduced, and a moderate level of impairment is observed in context-specific associative learning. We propose that mGluR1 is not "in line" in LTP production, but rather modulates the plasticity process, and hence affects context-specific associative learning.

Animals↗

PubMed1988

Constraints on water maze spatial learning in rats: implications for behavioral studies of brain damage and recovery of function.

In an effort to develop spatial learning tasks not requiring food or water deprivation for use in studies of recovery of function after brain damage, T-maze spatial alternation learning was examined in intact rats using water maze swim-escape procedures. Consistent with previous studies, rewarded spatial alternation involving food or water deprivation was readily learned by intact rats. However, none of the groups of rats trained in the swim-escape tasks learned to alternate goal arm choices in the water maze at reliable rates. This was true regardless of whether non-correction or correction procedures were used, and regardless of intertrial delay intervals. Although average alternation rates over sessions did increase from chance levels, the majority of the rats did not reach criterion levels, even with as many as 38 consecutive days of testing. In contrast, a conditional spatial alternation task in the water maze, using a win-shift procedure, was readily learned. Surprisingly, a win-stay version of this conditional spatial task was not learned over 21 days of testing. These unexpected constraints on spatial learning and memory processes in rats cannot be attributed simply to failure of spatial information processing, nor to strict limitations on working memory in swim-escape tasks, since excellent spatial navigation abilities have been documented, and mastery of at least some working-memory tasks have now been demonstrated in swim-escape tasks.

Animals↗

PubMed1992

Contribution of the cerebellum to neuropsychological functioning: evidence from a case of cerebellar degenerative disorder.

A detailed neuropsychological evaluation was performed on a patient with an idiopathic cerebellar degenerative disorder. Significant deficits were found in verbal and nonverbal intelligence, verbal associative learning, and visuospatial skills. These deficits were not readily explained by motor control difficulties. In contrast to the patient's moderately impaired language abilities, he was severely impaired on a test of verbal fluency and demonstrated mild naming deficits. Severe cerebellar parenchymal volume loss was demonstrated by magnetic resonance examination. Supratentorial structures showed only minimal posterior parietal and occipital sulcal prominence. On neurological examination, this patient had signs of severe involvement of the cerebellar systems and mild-to-moderate dysfunction of the corticospinal tract. As is characteristic of patients with cerebellar degeneration, there was neurophysiological evidence of subclinical involvement of auditory and somatosensory pathways at the level of the brain stem. Since relatively little cerebral cortical atrophy was noted in this patient, these findings suggest that an intact cerebellum is important for normal cognitive functions.

Adult↗

PubMed1992

Effects of chlorpromazine and lorazepam on explicit memory, repetition priming and cognitive skill learning in healthy volunteers.

To assess the influence of neuroleptics on explicit memory and two forms of implicit memory, repetition priming and cognitive skill learning, the effects of two low doses of chlorpromazine (12.5 and 25 mg orally) were contrasted to those of lorazepam (2.5 mg orally) and of a placebo using a free-recall task, a word-completion task and repeated testing on the Tower of Toronto puzzle, a version of the Tower of Hanoi puzzle. Seventy-two healthy volunteers took part in this double-blind study. Chlorpromazine spared free-recall and word-completion performance, but impaired the acquisition of a cognitive routine in the subjects who completed the first trials of the Tower of Toronto puzzle efficiently. Lorazepam induced an opposite pattern of memory disruption. These preliminary results suggest that chlorpromazine and lorazepam induced a double dissociation between priming and the acquisition of a cognitive routine. They provide evidence that the two forms of implicit memory rely upon distinct neurochemical systems, the latter, but not the former, being dependent upon dopaminergic systems.

Adult↗

PubMed1996

Affective learning: awareness and aversion.

In two studies, we investigated the influence of aversive and nonaversive reinforcers on startle reactivity, visceral responses, and self-report during Pavlovian conditioning. Furthermore, we assessed how awareness of the stimulus contingencies affect conditioned discrimination in the different response systems. Conditioned potentiation of the startle response was only observed in the context of aversive learning. Moreover, blink potentiation occurred without awareness of the relationship between the conditioned and unconditioned stimulus. In contrast, skin conductance conditioning was independent of the aversiveness of the reinforcer and was only obtained for those individuals who could correctly verbalize the stimulus contingency in a postconditioning recognition test. Cardiac responses varied with the task demands of the situation and covaried with individual response stereotypes.

Adult↗

PubMed2004

Robotic laparoscopic radical prostatectomy with a single assistant.

INTRODUCTION: As experience with robot-assisted laparoscopic radical prostatectomy (rLRP) grows, the importance of the role of the assistant cannot be overstated. Key elements of the operation, dependent on the assistant, have not been reported. The focus of this report was to describe the key elements, which include positioning of the patient and assistant port sites, appropriate equipment, and the assistant-dependent steps of the procedure. TECHNICAL CONSIDERATIONS: During the course of the initial 100 cases, we reviewed the patient and port site positioning and reviewed the videotapes to identify key elements of the assistant's role that facilitate rLRP. We identified three important elements pertaining to patient positioning. In contrast to standard port site recommendations, we found that dominant and nondominant handedness dictate the assistant port site locations. Finally, we identified specific steps of the procedure that require the assistant to have laparoscopic skills necessary for the console surgeon to dissect the bladder neck, seminal vesicles, rectum, and neurovascular bundles. CONCLUSIONS: The assistant in rLRP is critical to the success of rLRP, especially in the learning phases. Right or left-handed dominance determines on which side the assistant should be positioned. In contrast to the console surgeon, the assistant should have intermediate to advanced laparoscopic skills.

Dissection↗

PubMed1995

Methodological aspects of life events research in people with learning disabilities: a review and initial findings.

A review of the life events studies relevant to people with learning disabilities is discussed. Issues surrounding the collection of information by using a structured interview method as set out in the Life Events and Difficulties Schedule Manual and the adjustment of threat rating to accommodate the perspective of people with learning disabilities are presented as a result of conducting a pilot study. The importance of using a probing interview style in contrast to a checklist method and eliciting the parents/carers' perception of events is emphasized.

Adult↗