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PubMed2004

Incorporating problem-based learning into an obstetrics/gynecology clerkship: impact on student satisfaction and grades.

OBJECTIVE: The purpose of this study was to describe the effect of the problem-based learning method on student grade and on student and faculty satisfaction. STUDY DESIGN: The problem-based learning method was instituted at 2 of 5 obstetrics/gynecology clerkship sites. Students and faculty were surveyed, with the use of a Likert scale, regarding aspects of satisfaction with the clerkship. Responses were compared according to problem-based learning usage. Student performance was also assessed according to problem-based learning usage, with a comparison of several grade components. Statistical analysis involved t-tests and Kendall's tau-C. RESULTS: For the year that was assessed, 54 of 156 students used the problem-based learning method. Mean student satisfaction responses were significantly higher for students who used the problem-based learning method. Faculty satisfaction was also significantly higher for the problem-based learning method, compared with other teaching methods. Mean scores on the National Board of Medical Examiners subject examination were higher for problem-based learning but did not reach statistical significance. Grade distribution was not significantly different for the groups. CONCLUSION: The problem-based learning method was associated with improved student and faculty satisfaction and did not affect student grades negatively.

Adult↗
PubMed2006

Learning enhancement with neuropeptides.

OBJECTIVE: Previous work has demonstrated that two synthetic peptides can prevent prenatal alcohol-induced damage as assessed by prevention of learning abnormalities in adult offspring as well as improve outcome from traumatic brain damage. The current studies were undertaken to evaluate whether these peptides could enhance performance in a learning and memory paradigm when administered either prenatally or to aged mice. STUDY DESIGN: For prenatal treatment, C57Bl6/J mice were treated on gestational day 8 with 1 oral administration of D-NAP or D-SAL alone or D-NAP+D-SAL or a double dose of D-SAL. Control groups were same-regimen treated with vehicle alone. Learning was assessed in adult male offspring (35-50 days) by using the Morris water maze. To evaluate aged animals, 12-month-old mice were treated with D-NAP and D-SAL or vehicle alone daily and tested on the Morris water maze. RESULTS: Offspring exposed prenatally to D-NAP+D-SAL learned significantly faster than controls, with an earlier onset of learning and an overall decreased latency to find the hidden platform (P < .05). Animals exposed prenatally to either D-NAP or D-SAL alone learned similar to control, with a trend toward faster latencies. Aged animals who received D-NAP+D-SAL learned significantly faster than age-matched controls, with an earlier onset of learning (P < .05). CONCLUSION: Combined D-NAP+D-SAL enhanced learning in healthy young mice and aged mice. These findings suggest potential therapeutic interventions not only during a critical developmental period, but also in aged animals.

Age Factors↗
PubMed2005

The role of dopamine in cognitive sequence learning: evidence from Parkinson's disease.

Electrophysiological and computational studies suggest that nigro-striatal dopamine may play an important role in learning about sequences of environmentally important stimuli, particularly when this learning is based upon step-by-step associations between stimuli, such as in second-order conditioning. If so, one would predict that disruption of the midbrain dopamine system--such as occurs in Parkinson's disease--may lead to deficits on tasks that rely upon such learning processes. This hypothesis was tested using a "chaining" task, in which each additional link in a sequence of stimuli leading to reward is trained step-by-step, until a full sequence is learned. We further examined how medication (L-dopa) affects this type of learning. As predicted, we found that Parkinson's patients tested 'off' L-dopa performed as well as controls during the first phase of this task, when required to learn a simple stimulus-response association, but were impaired at learning the full sequence of stimuli. In contrast, we found that Parkinson's patients tested 'on' L-dopa performed better than those tested 'off', and no worse than controls, on all phases of the task. These findings suggest that the loss of dopamine that occurs in Parkinson's disease can lead to specific learning impairments that are predicted by electrophysiological and computational studies, and that enhancing dopamine levels with L-dopa alleviates this deficit. This last result raises questions regarding the mechanisms by which midbrain dopamine modulates learning in Parkinson's disease, and how L-dopa affects these processes.

Aged↗
PubMed2004

Behavior strategy learning in rat: effects of lesions of the dorsal striatum or dorsal hippocampus.

Depending on task demands, there is a growing body of evidence suggesting that the dorsal striatum plays a critical role in not only learning new response strategies but also in the inhibition of pre-existing strategies when a shift in strategy is required. The present experiment examined the effects of lesions of the dorsal striatum or dorsal hippocampus on acquisition of a response-learning rule and a place-learning rule in a Greek Cross version of the Morris water maze. Specifically, adult Long-Evans rats were prepared with either sham lesions or lesions to one of two subcortical areas of the brain considered necessary for processing nondeclarative or declarative memories, the dorsal striatum or the hippocampus, respectively. An analysis of the trial 2 performance pooled across reversals revealed hippocampus lesions induced accelerated acquisition when a response-learning rule was required. A much smaller enhancement effect was observed in dorsal striatum-lesioned animals in the place-learning paradigm. Dorsal hippocampus- and dorsal striatum-lesioned animals were highly impaired on place learning and response learning, respectively. The present results are congruent with a growing body of literature suggesting that different anatomical substrates are involved in the acquisition and maintenance of different types of information, that these processes can occur simultaneously and in parallel, and that the dorsal striatum is necessary for the mediation of stimulus-response learning, while the hippocampus is necessary to mediate the expression of place learning.

Animals↗
PubMed2006

Implicit oculomotor sequence learning in humans: Time course of offline processing.

Studies of manual and digital sequence learning indicate that motor memories continue to be processed after training has ended, following a succession of identifiable steps. However, it is not known whether this offline memory processing constitutes a basic feature of motor learning and generalizes to the implicit learning of a sequence of eye movements. To assess this hypothesis, we have created the serial oculomotor reaction time task (SORT). Participants were trained to the SORT then tested after either 30 min, 5 h or 24 h. During training, ocular reaction times decreased monotonically over practice of a repeated sequence, then increased when a different sequence was displayed, demonstrating oculomotor learning of the trained sequence. When tested 30 min after training, a significant gain in oculomotor performance was observed irrespective of the sequence learning. This gain was no longer present after 5 h. Remarkably, a gain in performance specific to the learned sequence emerged only 24 h after training. After testing, a generation task confirmed that most subjects learned implicitly the regularities of the sequence. Our results show that, as for manual or digital sequences, oculomotor sequences can be implicitly learned. The offline processing of oculomotor memories follows distinct stages in a way similar to those observed after manual or digital sequence learning.

Adult↗
PubMedDate not supplied

Designing high-quality interactive multimedia learning modules.

Modern research has broadened scientific knowledge and revealed the interdisciplinary nature of the sciences. For today's students, this advance translates to learning a more diverse range of concepts, usually in less time, and without supporting resources. Students can benefit from technology-enhanced learning supplements that unify concepts and are delivered on-demand over the Internet. Such supplements, like imaging informatics databases, serve as innovative references for biomedical information, but could improve their interaction interfaces to support learning. With information from these digital datasets, multimedia learning tools can be designed to transform learning into an active process where students can visualize relationships over time, interact with dynamic content, and immediately test their knowledge. This approach bridges knowledge gaps, fosters conceptual understanding, and builds problem-solving and critical thinking skills-all essential components to informatics training for science and medicine. Additional benefits include cost-free access and ease of dissemination over the Internet or CD-ROM. However, current methods for the design of multimedia learning modules are not standardized and lack strong instructional design. Pressure from administrators at the top and students from the bottom are pushing faculty to use modern technology to address the learning needs and expectations of contemporary students. Yet, faculty lack adequate support and training to adopt this new approach. So how can faculty learn to create educational multimedia materials for their students? This paper provides guidelines on best practices in educational multimedia design, derived from the Virtual Labs Project at Stanford University. The development of a multimedia module consists of five phases: (1) understand the learning problem and the users needs; (2) design the content to harness the enabling technologies; (3) build multimedia materials with web style standards and human factors principles; (4) user testing; (5) evaluate and improve design.

Computer Graphics↗
PubMed2006

Oculomotor and manual indexes of incidental and intentional spatial sequence learning during middle childhood and adolescence.

The goal of this study was to examine incidental and intentional spatial sequence learning during middle childhood and adolescence. We tested four age groups (8-10 years, 11-13 years, 14-17 years, and young adults [18+ years]) on a serial reaction time task and used manual and oculomotor measures to examine incidental sequence learning. Participants were also administered a trial block in which they were explicitly instructed to learn a sequence. Replicating our previous study with adults, oculomotor anticipations and response times showed learning effects similar to those in the manual modality. There were few age-related differences in the sequence learning indexes during incidental learning, but intentional learning yielded differences on all indexes. Results indicate that the search for regularities and the ability to learn a sequence rapidly under incidental conditions are mature by 8 to 10 years of age. In contrast, the ability to learn a sequence intentionally, which requires cognitive resources and strategies, continues to develop through adolescence.

Adolescent↗
PubMed2006

Functional imaging of sequence learning in Parkinson's disease.

Sequence learning, a cognitive task linked to cortico-striatal function, is impaired in Parkinson's disease (PD). We chose this task as a behavioral paradigm to study the functional architecture of PD in treated and untreated conditions. In our studies, participants were scanned with H(2)(15)O while performing a kinematically controlled motor sequence learning task and a matching motor baseline task. Experiments revealed that a specific sequence learning network predicts learning in normal subjects, and in independent cohorts of early and advanced PD patients. The analysis of the relationship of network activity to learning performance revealed diverging influences of dopaminergic therapy and deep brain stimulation (DBS). DBS of the internal GP and of STN increased network activity and task performance, while levodopa decreased both measures. In separate studies, we investigated the role of dopaminergic modulation on brain activation during sequence learning. In healthy subjects dopamine transporter (DAT) binding correlated with learning-related brain activation in prefrontal, premotor and cingulate cortices, and in the thalamus. By contrast, in PD most of these regional relationships were lost. Only ventral and dorsolateral prefrontal cortex activation correlated with caudate dopaminergic input. In a final set of studies, we found a significant decline in learning performance in early stage PD patients followed over the course of 2 years. Longitudinal declines in learning-related activation were found in parietal areas, while concomitant increases were localized to the left hippocampus. These observations support hypotheses on disease-stage and task-specific effects within the different cortico-striato-pallido-thalamocortical loops and the mesocortical system in PD.

Aged↗
PubMed2006

Pharmacological and molecular enhancement of learning in aging and Alzheimer's disease.

When animals learn hippocampus-dependent associative and spatial tasks such as trace eyeblink conditioning and the water maze, CA1 hippocampal neurons become more excitable as a result of reductions in the post-burst, slow afterhyperpolarization. The calcium-activated potassium current that mediates this afterhyperpolarization is activated by the calcium influx that occurs when a series of action potentials fire and serves as a modulator of neuronal firing frequency. As a result, spike frequency accommodation is also reduced after learning. Neuronal calcium buffering processes change and/or voltage-dependent calcium currents increase during aging; leading to enhancements in the slow afterhyperpolarization, increased spike frequency accommodation and age-associated impairments in learning. We describe a series of studies done to characterize this learning-specific enhancement in intrinsic neuronal excitability and its converse in aging brain. We have also combined behavioral pharmacology and biophysics in experiments demonstrating that compounds that increase neuronal excitability in CA1 pyramidal neurons also enhance learning rate of hippocampus-dependent tasks, especially in aging animals. The studies reviewed here include those using nimodipine, an L-type calcium current blocker that tends to cross the blood-brain barrier; metrifonate, a cholinesterase inhibitor; CI1017, a muscarinic cholinergic agonist; and galantamine, a combined cholinesterase inhibitor and nicotinic agonist. Since aging is the chief risk factor for Alzheimer's disease, a disease that targets the hippocampus and associated brain regions and markedly impairs hippocampus-dependent learning, these compounds have potential use as treatments for this disease. Galantamine has been approved by the USDA for this purpose. Finally, we have extended our studies to the TG2576 transgenic mouse model of Alzheimer's disease (AD), that overproduces amyloid precursor protein (APP) and increases levels of toxic beta-amyloid in the brain. Not only do these mice show deficits in hippocampus-dependent learning as they age, but their hippocampal neurons show a reduced capacity to increase their levels of intrinsic excitability with reductions in the slow afterhyperpolarization after application of the muscarinic agonist carbachol. These TG2576 APP overproducing mice were crossed with BACE1 knockout mice, that do not produce beta-amyloid because cleavage of APP by the beta-site APP cleaving enzyme 1 (BACE1) is a critical step in its formation. Not only was hippocampus-dependent learning rescued in the bigenic TG2576-BACE1 mice, but the capacity of hippocampal neurons to show normal enhancements of intrinsic excitability was restored. The series of studies reviewed here support our hypothesis that enhancement in intrinsic excitability by reductions in calcium-activated potassium currents in hippocampal neurons is an important cellular mechanism for hippocampus-dependent learning.

Aging↗
PubMed2004

Self direction in a problem based learning program.

Baccalaureate nursing graduates must enter their professional careers with the understanding and ability to engage in continuing learning in order to ensure competence in professional practice. The graduate's ability to be self directed in learning is an important indication of the ability to pursue continuing learning as a practitioner. It has been surmised that Problem Based Learning nursing programs facilitate the development of abilities to become self directed in learning. A quasi-experimental design using the self directed learning readiness scale (SDLRS) was used to examine the self directed learning (SDL) of students at the beginning and end of one year in a problem based learning (PBL) program. In order to complement the quantitative data, year end focus group interviews were held with students to explore their experiences with SDL. Students demonstrated average self directed learning readiness scores at the beginning and end of the first year in the PBL program. Although students did not demonstrate any increase in SDLRS at the end of one year in a PBL program, they were able to describe themselves as having developed many of the documented characteristics associated with self directed learners.

Adolescent↗
PubMed2003

Spatial learning is delayed and brain-derived neurotrophic factor mRNA expression inhibited by administration of MK-801 in rats.

Brain-derived neurotrophic factor (BDNF) is involved in activity-dependent plasticity and interacts with the neurotransmitter glutamate. Glutamate N-methl-D-aspartate (NMDA) receptor activation increases BDNF expression, while BDNF facilitates NMDA activity, with both involved in spatial learning. Administration of the NMDA receptor antagonist MK-801 can impair this leaning. The interaction between NMDA and BDNF in learning is examined in this study. Adult male Sprague-Dawley rats received either i.p. MK-801 or saline and were trained to locate a submerged water maze platform. Sedentary and activity yoked groups were included for biochemical comparisons. Control rats quickly learned the platform location while MK-801-treated rats learned at a significantly slower rate (P < 0.0001). In situ hybridization for hippocampal BDNF mRNA indicated significant increases in the yoked and learning groups. However, MK-801 attenuated the BDNF mRNA increase in the learning and activity-yoked conditions (P < 0.05). Administration of MK-801 to the sedentary group did not alter baseline mRNA levels. These data suggest that BDNF expression is important for NMDA-dependent learning and memory. Interestingly, learning still occurs across trials independent of the NMDA and BDNF interaction. Increases in BDNF and NMDA activity may be significant components in learning and memory, and modulation of these systems may be beneficial for developing strategies to improve cognitive function.

Animals↗
PubMed2005

Conserving total synaptic weight ensures one-trial sequence learning of place fields in the hippocampus.

The hippocampus plays a critical role in the rapid acquisition of information from a novel experience. Recent theoretical studies on the rat hippocampus have shown the possibility of behavioral sequence learning in a single traversal experience by theta phase coding. Specifically, previous work using computer simulations demonstrated that the extent of overlap among individual events of sequence and rat running velocity should be quantitatively incorporated into the learning rule to ensure one-trial sequence learning. These extents of overlap- and running velocity-dependent properties in the learning rule are called the input-dependent regulation of the learning rule. However, the biological meaning of such learning properties remains poorly understood. In this study, we quantitatively derive these learning properties with mathematical analyses. We further find that the input-dependent regulation of the learning rule allows maintenance of total synaptic weight over a given neuron during one-trial learning. Our results predict that a homeostatic plasticity mechanism should exist for conserving total synaptic weight on a rapid timescale.

Action Potentials↗
PubMed2006

Hippocampal synapsin I, growth-associated protein-43, and microtubule-associated protein-2 immunoreactivity in learned helplessness rats and antidepressant-treated rats.

Learned helplessness rats are thought to be an animal model of depression. To study the role of synapse plasticity in depression, we examined the effects of learned helplessness and antidepressant treatments on synapsin I (a marker of presynaptic terminals), growth-associated protein-43 (GAP-43; a marker of growth cones), and microtubule-associated protein-2 (MAP-2; a marker of dendrites) in the hippocampus by immunolabeling. (1) Learned helplessness rats showed significant increases in the expression of synapsin I two days after the attainment of learned helplessness, and significant decreases in the protein expression eight days after the achievement of learned helplessness. Subchronic treatment of naïve rats with imipramine or fluvoxamine significantly decreased the expression of synapsin I. (2) Learned helplessness increased the expression of GAP-43 two days and eight days after learned helplessness training. Subchronic treatment of naïve rats with fluvoxamine but not imipramine showed a tendency to decrease the expression of synapsin I. (3) Learned helplessness rats showed increased expression of MAP-2 eight days after the attainment of learned helplessness. Naïve rats subchronically treated with imipramine showed a tendency toward increased expression of MAP-2, but those treated with fluvoxamine did not. These results indicate that the neuroplasticity-related proteins synapsin I, GAP-43, and MAP-2 may play a role in the pathophysiology of depression and the mechanisms of antidepressants.

Analysis of Variance↗
PubMed2006

Long-term consequences of early experience on adult avoidance learning in female rats: role of the dopaminergic system.

Following our hypothesis that juvenile emotional and/or cognitive experience should affect learning performance at preweaning age as well as adulthood, the present study in female Wistar rats aimed to examine the impact of (i) avoidance training at preweaning age, (ii) exposure to repeated maternal separation, (iii) the combination of both, and (iv) the blockade of dopaminergic neurotransmission on adult two-way active avoidance learning in rats. We found that preweaning, i.e. three week old, rats were less capable of avoidance learning compared to adults. Our main findings revealed that preweaning avoidance training alone improved avoidance learning in adulthood. Furthermore, maternal separation alone also improved avoidance learning in preweaning and in adult rats, but this effect of maternal separation did not add up to the beneficial effect of preweaning avoidance training on adult learning. In addition, the pharmacological blockade of dopamine receptors during preweaning avoidance training via systemic application of haloperidol impaired preweaning avoidance performance in a dose-dependent manner. Testing the haloperidol-treated preweaning presumed "non-learners" as adults revealed that they still showed improved learning as adults. Taken together, our results strongly support the hypothesis that emotional as well as cognitive experience at preweaning age leaves an enduring "memory trace," which can facilitate learning in adulthood. Our pharmaco-behavioral studies suggest that unlike the adult brain, preweaning learning and memory formation is less dependent on dopaminergic mechanisms, which raises the intriguing question of possible alternative pathways.

Age Factors↗
PubMed2004

Accelerated senescence prone mouse-8 shows early onset of deficits in spatial learning and memory in the radial six-arm water maze.

Available data indicate that the senescence-accelerated prone mouse 8 (SAMP8) is an appropriate model of brain aging, with impairments in nonspatial learning and memory beginning as early as 2 months of age, and spatial learning and memory deficiencies not becoming apparent until after 4 months of age. However, with other strains (e.g., C57BL mice), the impairment in spatial memory was found earlier than that in nonspatial memory. We considered the possibility that the observed differences could be due to strain-specific differences in the training equipment. In the present study, a new optimized testing apparatus-the radial six-arm water maze (RAWM)-for detecting spatial learning and memory in mice, was employed, to determine whether there is impairment of spatial learning and memory in young SAMP8. The relationship between the spatial learning measures observed with the RAWM and the Morris maze, a classic spatial learning and memory testing apparatus, was also explored. It was found that, in the RAWM, rather than in the Morris maze, the impairment in spatial learning could be measured in SAMP8 mice as early as 3 months old, and the impairment in spatial memory in SAMP8 mice aged 5 months. These results suggested that the spatial learning and memory deficiencies could be found in early life of SAMP8 mice, and that RAWM and Morris maze each detect different aspects of spatial learning and memory.

Aging↗
PubMed1998

Spontaneous and artificial lesions of magnocellular reticular formation of brainstem deteriorate avoidance learning in senescence-accelerated mouse SAM.

The role of the magnocellular reticular formation (MGRF) of the brainstem on learning and memory was examined in memory-deficient mice with spontaneous spongy degeneration in the brainstem (senescence-accelerated mouse, SAMP8) and control mice (accelerated-senescence resistant mouse, SAMR 1). SAMP8 showed spontaneous age-related impairment of learning and memory, as determined by passive and active avoidance responses. The deficits of learning and memory function in passive avoidance performances began at two months of age and increased with ageing. In the brains of SAMP8 at one month of age and older, spongy degeneration was mainly observed in the brainstem, while no vacuoles were evident in SAMR1 control (normal ageing mouse) brains in the age range tested (up to 12 months). The vacuolization in SAMP8 was marked in the MGRF, especially in the dorsomedial MGRF. Quantitative analysis of the vacuolization showed that the total area and number of vacuoles in the MGRF increased with age, and they were affected by the degree of deficits in learning and memory. The latency 24 h after footshock in passive avoidance tests decreased with the increase in total area and number of vacuoles in MGRF. The number of shocks in active avoidance tests increased with the increase in total number and area of vacuoles. Thus, learning and memory ability in passive and active avoidance responses deteriorated with enlargement in the vacuolated area in MGRF, and it was assumed that MGRF (especially, the dorsomedial part) possesses functions related to learning and memory. To confirm this notion, behavior and memory tests (passive avoidance and active avoidance tests, open field tests and shock sensitivity measurements) were carried out in SAMR1 mice, whose bilateral dorsomedial MGRF was destroyed electrolytically (MGRF-lesioned mice). The MGRF-lesioned mice showed no difference from sham mice in sensory threshold or open field activity; however, there was severe deterioration in passive avoidance behavior and impairment in the active avoidance performances. From the results in SAMP8 and MGRF-lesioned mice, it was confirmed that MGRF (especially the dorsomedial part) has functions related to learning and memory, and is one part in the learning and memory system of the brain. Thus, SAMP8 can serve as a model of RF-lesioned mice with impaired learning and memory functions.

Aging↗
PubMed2003

Word, nonword, and visual paired associate learning in Dutch dyslexic children.

Verbal and non-verbal learning were investigated in 21 8-11-year-old dyslexic children and chronological-age controls, and in 21 7-9-year-old reading-age controls. Tasks involved the paired associate learning of words, nonwords, or symbols with pictures. Both learning and retention of associations were examined. Results indicated that dyslexic children had difficulty with verbal learning of both words and nonwords. In addition, analysis of the errors made during nonword learning showed that both phonological errors and general learning errors were distributed similarly for the reading groups. This suggests that nonword learning in dyslexics is slower, but not qualitatively different from normal readers. Furthermore, no differences were found between the dyslexics and age-matched normal readers on non-verbal learning. Long-term retention of the learned visual-verbal associations (both words and nonwords) was not impaired in dyslexic children as compared to normal readers. Finally, phonological awareness ability was assessed. Dyslexics performed worse than age-matched normal readers, but similar to reading-age controls.

Awareness↗
PubMed1984

Current status of the neuromaturational examination as an index of learning disability.

To further define the role of the neuromaturational examination in determining the presence of learning problems, we examined 104 boys, ages 9.5 to 14.1 years, representing three populations of school children: normal (32 boys), gifted (37), and learning disabled (35). Information concerning each child's behavior and development was obtained through a parent questionnaire; cognitive ability and academic achievement were measured by the Wechsler Intelligence Scales for Children (revised) and Woodcock -Johnson Psychoeducational Battery, respectively. Significant relationships emerged between the number of neuromaturational signs and data group membership (LD greater than N greater than G,P less than 0.05). The number of neuromaturational signs decreased with age for normal (P less than 0.05) and gifted (P less than 0.05) children, but not for the learning-disabled group. Tasks that differentiated the normal and learning disabled were entered into a stepwise discriminant analysis, with a resulting classification accuracy of 93.1% and 100% for the normal and learning-disabled boys, respectively. Analysis of covariance indicated that differences in performance of the three groups may reflect IQ differences among the populations. Learning disabled boys were more likely to exhibit synkinesis than normal boys, but gifted boys did not differ from the learning disabled in the frequency of synkinesis. Our data indicate that, although a composite set of neuromaturational tasks can discriminate normal and learning-disabled boys with a high level of accuracy, caution is urged because the findings may be more related to overall intelligence than to a specific learning disability.

Adolescent↗