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PubMed2006

The self-reported learning style preferences of female Macmillan clinical nurse specialists.

Individuals typically adopt and prefer one or two learning styles and therefore, by default, remaining learning styles are underutilised. Insight into learning style preferences confers interpersonal benefits to both learners and teachers. Enlightened learners and teachers can identify their dominant learning styles and potentially strengthen underutilised ones. Findings from a retrospective study commissioned by Macmillan Cancer Relief that investigated learning style preferences of 137 female Macmillan Clinical Nurse Specialists (CNSs) showed that the majority (73.7%) displayed a strong-very strong preference for one or two learning styles. Mean scores across four learning styles were highest for the reflector learning style (mu=14.85+/-3.16) followed by theorist (mu=12.2+/-2.87), pragmatist (mu=11.5 (2.85) and activist (mu=7.95+/-3.11). An understanding of individual learning style preferences, particularly the strengthening of those that are underutilised is said to cultivate both flexible and resourceful learners and effective teachers. Such characteristics would confer considerable benefits within the remit of a Macmillan CNS position.

Attitude of Health Personnel↗
PubMed2004

Striatal dopamine and learning strategy-an (123)I-FP-CIT SPECT study.

UNLABELLED: Patients with Parkinson's disease (PD) have difficulty in processing learning tasks that lack external guidelines and, consequently, necessitate the subjects to generate their own problem-solving strategy. While the contribution of striatal dopaminergic deficiency to PD-specific motor symptoms is well established, its role in the PD-characteristic deviant learning style remains unclear. The aim of this study was to assess the relation between striatal dopamine activity as revealed by single photon emission computed tomography (SPECT) with (123)I-FP-CIT, a ligand for the dopamine transporter (DaT), and type of learning strategy, as identified by the California Verbal Learning Task (CVLT) in 19 patients with probable PD. The results showed a robust inverse correlation between striatal dopamine DaT binding and the externally guided, serial learning strategy: the lower the DaT in caudate nucleus as well as in putamen, the more the patient group appeared to rely on externally structured learning. Additionally, a significant positive correlation was found between caudatal DaT activity and the internally generated, semantic learning strategy. Unlike these strategic learning characteristics, IQ equivalent and recall total score appeared to vary independently from striatal DaT availability. CONCLUSION: our findings provide direct evidence that striatal dopaminergic activity is specifically involved in the regulation of strategic learning processes.

Adult↗
PubMed2005

The implicit sequence learning deficit in patients with Parkinson's disease: a matter of impaired sequence integration?

Despite the wealth of research investigating the serial reaction time (SRT) learning abilities of people with Parkinson's disease (PD), the role of the basal ganglia in implicit sequence learning remains largely unclear. The present research sought to examine the ability of people with PD to implicitly learn simultaneously operating sequences and integrate patterned information from each sequence dimension. Using a version of the SRT which reduced motor demands, the present experiment investigated the implicit learning of a spatial sequence, a stimulus-response sequence, and an integrated spatial/stimulus-response sequence, all of which are usually confounded in the standard SRT task. Whereas both PD and control groups demonstrated robust learning for the individual spatial and response sequences, only control participants evidenced learning for the integrated sequence. Further, unlike implicit learning for the spatial and object sequences, impaired integrated sequence acquisition was specifically related to the severity of patients' PD symptomatology. The implicit learning deficits of PD patients are discussed with regard to the role played by the basal ganglia in integrative sequence learning in the SRT.

Aged↗
PubMedDate not supplied

Learning impairment caused by a toxin produced by Pfiesteria piscicida infused into the hippocampus of rats.

Pfiesteria piscicida, an estuarine dinoflagellate, which has been shown to kill fish, has also been associated with neurocognitive deficits in humans. With a rat model, we have demonstrated the cause-and-effect relationship between Pfiesteria exposure and learning impairment. In several studies, we have replicated the finding in Sprague-Dawley rats that exposure to fixed acute doses of Pfiesteria cells or filtrates caused radial-arm maze learning impairment. Recently, this finding of Pfiesteria-induced learning impairment in rats has been independently replicated in another laboratory as well. We have demonstrated significant Pfiesteria-induced learning impairment in both the win-shift and repeated-acquisition tasks in the radial-arm maze and in reversal learning in a visual operant signal detection task. These learning impairments have been seen as long as 10 weeks after a single acute exposure to Pfiesteria. In the current study, we used a hydrophilic toxin isolated from clonal P. piscicida cultures (PfTx) and tested its effect when applied locally to the ventral hippocampus on repeated acquisition of rats in the radial-arm maze. Toxin exposure impaired choice accuracy in the radial-arm maze repeated acquisition procedure. The PfTx-induced impairment was seen at the beginning of the session and the early learning deficit was persistent across 6 weeks of testing after a single administration of the toxin. Eventually, with enough practice, in each session, the PfTx-exposed rats did learn that session's problem as did control rats. This model has demonstrated the cause-and-effect relationship between exposure to a hydrophilic toxin produced by P. piscicida and learning impairment, and specifically that the ventral hippocampus was critically involved.

Animals↗
PubMed2004

Functional characteristics of the associative areas of the cortex involved in visual information discrimination learning processes in monkeys.

Experiments on three groups of rhesus macaques (intact and with bilateral removal of field 7 and the sulcus principalis) were performed to study the functional characteristics of the associative areas of the cortex while the monkeys learned visual discrimination. Significant differences in learning processes associated with removal of structures and the properties of the stimuli were seen in all animals, in the form of different types of learning curves. As compared with intact monkeys, removal of field 7 had no effect on learning processes for images with properties such as spatial frequency, color, and animal images, though there was a significant worsening in the characteristics of learning during visual discrimination of spatial relationships between objects. Learning processes became unstable, the number of peaks and troughs on learning curves increased, and as a result the training periods were significantly lengthened and 85% of the animals were unable to achieve the learning criterion. Removal of the sulcus principalis significantly worsened the characteristics of discrimination of the sizes of geometric objects, the spatial relationships between them, and stimuli of different colors. The stable reaction time and the probability of refusal in most cases also increased for monkeys of both these groups. Cluster analysis based on the quantitative characteristics of learning processes, despite individual differences between the monkeys, demonstrated a tendency for stimuli to be separated into classes corresponding to different types of information. These data show that the result of sensory processing is that several (at least three) functional visual information flows are generated and that different areas of the cortex deal with these different flows.

Animals↗
PubMed1997

Effectiveness of problems used in problem-based learning.

Where problem-based learning (PBL) is the main method used in medical curricula, the literature suggests that it is crucial that the problems used are effective in facilitating students to identify relevant learning issues. These learning issues guide the students' studying. The present investigation explores the extent to which students identify relevant issues following exposure to prepared paper problems. In the preparatory year, in an Introduction to Medicine module, four groups of students were exposed to six themes (Health Care System, Environment and Health, Alternative and Islamic Medicine, Chronic Illness, Infectious Diseases, and Prevention and Health Promotion). Each group had two facilitators per theme. Having discussed the prepared problems, the students identified learning issues which were collected for the purpose of the study. Two content experts, using a Likert scale, analysed learning issues for their concordance to staff objectives per theme. Kappa coefficients were computed for the six PBL themes in order to assess inter-rater agreement. Learning issues identified as having no relationship to theme objectives were further analysed for their relevance to theme objectives. No objective was totally omitted by any student group. There was a 100% concordance of objectives to learning issues demonstrated over four themes. The relationship of learning issues to theme objectives ranged from 55-85% in the theme on health care system, and 73-94% in the theme on environment and health. Irrelevant learning issues were identified in the first two PBL themes addressed. Kappa coefficients over the six PBL themes varied from 0.49 to 0.82.

Education, Medical, Undergraduate↗
PubMed2005

Brief report: errorless versus errorful learning as a memory rehabilitation approach in Alzheimer's Disease.

Previous studies concerned with the use of errorless learning (EL) in memory rehabilitation of patients with Alzheimer's disease (AD) combined EL with other techniques, such as expanded rehearsal, to facilitate learning. These studies focused on the re-learning of previously familiar information and did not investigate the learning of novel information. The aim of the present study was to investigate if EL provides a better training technique for AD patients than errorful learning (EF). For this purpose, learning of familiar material and learning of novel associations in four patients with probable AD was compared under EL and EF conditions. Combined data analysis demonstrated a significant advantage of EL over EF both for old and novel learning. However, patients also learned significantly in the EF condition and the EL effect was not large enough to reach significance on an individual level. It is suggested that EL may be most beneficial for patients with profound amnesia, and in situations that make effortful processing difficult, but that residual explicit memory capacities may override EL benefits.

Aged↗
PubMed2006

Development switch in neural circuitry underlying odor-malaise learning.

Fetal and infant rats can learn to avoid odors paired with illness before development of brain areas supporting this learning in adults, suggesting an alternate learning circuit. Here we begin to document the transition from the infant to adult neural circuit underlying odor-malaise avoidance learning using LiCl (0.3 M; 1% of body weight, ip) and a 30-min peppermint-odor exposure. Conditioning groups included: Paired odor-LiCl, Paired odor-LiCl-Nursing, LiCl, and odor-saline. Results showed that Paired LiCl-odor conditioning induced a learned odor aversion in postnatal day (PN) 7, 12, and 23 pups. Odor-LiCl Paired Nursing induced a learned odor preference in PN7 and PN12 pups but blocked learning in PN23 pups. 14C 2-deoxyglucose (2-DG) autoradiography indicated enhanced olfactory bulb activity in PN7 and PN12 pups with odor preference and avoidance learning. The odor aversion in weanling aged (PN23) pups resulted in enhanced amygdala activity in Paired odor-LiCl pups, but not if they were nursing. Thus, the neural circuit supporting malaise-induced aversions changes over development, indicating that similar infant and adult-learned behaviors may have distinct neural circuits.

Age Factors↗
PubMedDate not supplied

Sound sequence discrimination learning motivated by reward requires dopaminergic D2 receptor activation in the rat auditory cortex.

We have previously reported that sound sequence discrimination learning requires cholinergic inputs to the auditory cortex (AC) in rats. In that study, reward was used for motivating discrimination behavior in rats. Therefore, dopaminergic inputs mediating reward signals may have an important role in the learning. We tested the possibility in the present study. Rats were trained to discriminate sequences of two sound components, and licking behavior in response to one of the two sequences was rewarded with water. To identify the dopaminergic inputs responsible for the learning, dopaminergic afferents to the AC were lesioned with local injection of 6-hydroxydopamine (6-OHDA). The injection attenuated sound sequence discrimination learning, while it had no effect on discrimination between the sound components of the sequence stimuli. Local injection of 6-OHDA into the nucleus accumbens attenuated sound discrimination learning. However, not only discrimination learning of sound sequence but also that of the sound components were impaired. SCH23390 (0.2 mg/kg, i.p.), a D1 receptor antagonist, had no effect on sound sequence discrimination learning, while it attenuated the licking behavior to unfamiliar stimuli. Haloperidol (0.5 mg/kg, i.p.), a D2 family antagonist, attenuated sound sequence discrimination learning, while it had no clear suppressive effect on discrimination of two different sound components and licking. These results suggest that D2 family receptors activated by dopaminergic inputs to the AC are required for sound sequence discrimination learning.

Acoustic Stimulation↗
PubMed1999

Procedural learning is impaired in patients with prefrontal lesions.

OBJECTIVES: To 1) determine the effect of prefrontal cortex lesions on procedural learning (PL), measured by a serial reaction-time task (SRTT); 2) confirm whether visuomotor PL is lateralized to one hemisphere; and 3) clarify the relation between visuomotor sequence learning and verbal sequence learning, working memory, and executive functions. BACKGROUND: Previous cognitive neuroscience research has implicated the prefrontal cortex in visuomotor PL but there is a lack of studies examining patients with prefrontal cortex lesions. METHODS: We studied 22 patients with strictly unilateral prefrontal cortex lesions (traumatic, ischemic, hemorrhagic, or tumors) and 52 cognitively intact controls matched for age, sex, and educational level. We administered to subjects long (10-item sequence) and short (4-item sequence) versions of the SRTT. With the long version, each hand was evaluated separately. Learning was indicated by the shortening of response times (RT) and decrease in errors across the sequential blocks and, most importantly, the rebound increase in RTs and errors when comparing the last sequence block with the next random block. Frontal lobe functions and verbal sequence learning were also assessed. RESULTS: Patients with unilateral prefrontal cortex lesions show PL impairment that involves both hands, although more errors were observed when the hand contralateral to the lesion was performing. Only those patients whose lesions were >2 cm in diameter were impaired. Neuropsychologic evaluation indicated impaired verbal sequence learning and executive function deficits. Patients with poorer working memory and verbal sequence learning were also more impaired in visuomotor sequence learning. CONCLUSIONS: The prefrontal cortex has a role in PL and is part of the neural circuit that mediates this type of learning.

Adult↗
PubMed1999

A partial agonist at strychnine-insensitive glycine sites facilitates spatial learning in aged rats.

1-Aminocyclopropanecarboxylic acid (ACPC) is a high affinity ligand at strychnine-insensitive glycine sites of the N-methyl-D-aspartate (NMDA) channels and exhibits partial agonist properties in both biochemical and electrophysiological measures. While ACPC was reported active in animal models used to evaluate potential antidepressants and anxiolytics, its effects on learning and memory are unknown. In the present study we investigated the effects of ACPC on spatial learning in the Morris water maze. On a schedule of 12 learning trials, one trial per day, mature male Wistar rats (3 months of age) rapidly acquired the task. Electroconvulsive shocks applied after each of the learning trials markedly inhibited the consolidation of spatial memory. Administration of either a muscarinic agonist, arecoline (1 mg/kg) or ACPC (250 or 400 mg/kg) 20 min before each of the learning trials did not affect the acquisition of spatial learning. Aged (16 months old) male Wistar rats demonstrated difficulties in the acquisition of spatial learning task. In these subjects, ACPC administered 20 min before each of the learning trials at a dose of 400, but not 250 mg/kg, facilitated the acquisition of spatial memory as indicated on trials 3-5. ACPC did not affect the strength of spatial memory as assessed at the end of conditioning, by measuring swimming behavior of rats in the pool with platform removed. It is suggested that ACPC may alleviate learning deficits observed in the elderly.

Age Factors↗
PubMedDate not supplied

[Learning and memory].

INTRODUCTION: The paper briefly reviews current knowledge on learning and memory processes, considered at the behavioral, cognitive and neural levels. DEVELOPMENT: After establishing the distinction between different learning processes (behavioral learning, skill acquisition and information acquisition processes), the specific learning phenomena belonging to each of these varieties are analyzed. Associative learning is described as a behavioral (pavlovian conditioning and instrumental learning) and cognitive (predictive learning and categorization) process. Also described are the properties of perceptual and motor learning, as those of the processes by which cognitive skills (e.g., rule learning) are acquired. Then, the distinction between short-term and long-term memory is discussed, referring to short-term memory as a working memory system that assists the performance of a variety of thinking and reasoning tasks. Finally, the two main long-term memory theories are discussed, considering the semantic/episodic and implicit/explicit memory dichotomies.

Animals↗
PubMed2001

Evaluation of problem-based learning: a lecturer's perspective.

INTRODUCTION: The exponential growth in medical/dental knowledge and the ever-expanding influence and sophistication of information technologies have placed a burden of responsibilities on dental educators to fashion out a curriculum that can prepare students to face the coming challenges in the new millennium. Consequently, a curriculum reform took place in the Faculty of Dentistry, National University of Singapore in 1997. Problem-based learning (PBL) was first introduced to the Faculty in 1996 as a pilot project to the 4th year. The purpose of this project was to evaluate the 4-year experience in PBL teaching and learning from the lecturers' point of view. MATERIALS AND METHODS: All 12 lecturers, who had been involved in the PBL teaching, participated in this questionnaire survey, which was composed of 17 questions with a 5-digit Likert scale. Data analysis was carried out using the Spearman's correlation, t-test, and the Mann-Whitney U test. RESULTS: Six female, 5 male and 1 unidentified lecturers were recruited into this survey with a 100% response rate. In general, lecturers learned more in teaching PBL and significantly took pleasure in the interactive learning and self-directed learning modes inherent to PBL (P = 0.004). Compared to the male lecturers, female lecturers had a greater propensity to feel that PBL teaching might not be cost-effective (P = 0.03). Senior lecturers felt more fulfilled compared with the younger ones (P = 0.026). Those lecturers who enjoyed the interactive learning experience in PBL seemed to like the self-directed learning and felt more fulfilled through teaching PBL compared to the traditional teaching (TT) (P < 0.01). They also felt that PBL may be cost-effective (P < 0.01). Lecturers did not have difficulties in being a facilitator (P = 0.04). Interestingly, lecturers who found difficulties in being a facilitator for the PBL class seemed to learn more in teaching PBL classes than in TT (P < 0.05). Overall, lecturers would like to suggest more PBL to be incorporated into the curriculum (P = 0.02). Nevertheless, lecturers were concerned about the knowledge gaps in students learning with PBL (P = 0.01) and the time constraint of students (P = 0.002). CONCLUSION: The results of this study reveal the pros and cons of the current PBL teaching method and may thus provide proper guidelines to shape the further development of PBL in our faculty.

Age Factors↗
PubMed2003

Switching memory systems during learning: changes in patterns of brain acetylcholine release in the hippocampus and striatum in rats.

This experiment measured acetylcholine (ACh) release simultaneously in the hippocampus and striatum while rats were trained in a cross maze. Consistent with past findings, rats initially showed learning on the basis of place (i.e., turning to the correct position relative to the room), but after extensive training, rats shifted to learning on the basis of response (i.e., turning to the right/left to find the food). Profiles of ACh release in the hippocampus and striatum were markedly different during training. In the hippocampus, ACh release increased by approximately 60% at the onset of training and remained at that level of release throughout training, even after the rats began to show learning on the basis of turning rather than place. In the striatum, increases in ACh release occurred later, reaching asymptotic increases of 30-40%, coincident with a transition from expressing place learning to expressing response learning. These findings suggest that the hippocampal and striatal systems both participate in learning in this task, but in a manner characterized by differential activation of the neural systems. The hippocampal system is apparently engaged first before the striatum is activated and, to the extent the hippocampus is important for place learning, promotes the use of a place solution to the maze. Later in training, although the hippocampus remains activated, the striatum is also activated in a manner that may enable the use of a response strategy to solve the maze. These findings may offer a neurobiological marker of a transition during skill learning from declarative to procedural learning.

Acetylcholine↗
PubMed2003

Dissociable contributions of the orbitofrontal and infralimbic cortex to pavlovian autoshaping and discrimination reversal learning: further evidence for the functional heterogeneity of the rodent frontal cortex.

To examine possible heterogeneity of function within the ventral regions of the rodent frontal cortex, the present study compared the effects of excitotoxic lesions of the orbitofrontal cortex (OFC) and the infralimbic cortex (ILC) on pavlovian autoshaping and discrimination reversal learning. During the pavlovian autoshaping task, in which rats learn to approach a stimulus predictive of reward [conditional stimulus (CS+)], only the OFC group failed to acquire discriminated approach but was unimpaired when preoperatively trained. In the visual discrimination learning and reversal task, rats were initially required to discriminate a stimulus positively associated with reward. There was no effect of either OFC or ILC lesions on discrimination learning. When the stimulus-reward contingencies were reversed, both groups of animals committed more errors, but only the OFC-lesioned animals were unable to suppress the previously rewarded stimulus-reward association, committing more "stimulus perseverative" errors. In contrast, the ILC group showed a pattern of errors that was more attributable to "learning" than perseveration. These findings suggest two types of dissociation between the effects of OFC and ILC lesions: (1) OFC lesions impaired the learning processes implicated in pavlovian autoshaping but not instrumental simultaneous discrimination learning, whereas ILC lesions were unimpaired at autoshaping and their reversal learning deficit did not reflect perseveration, and (2) OFC lesions induced perseverative responding in reversal learning but did not disinhibit responses to pavlovian CS-. In contrast, the ILC lesion had no effect on response inhibitory control in either of these settings. The findings are discussed in the context of dissociable executive functions in ventral sectors of the rat prefrontal cortex.

Animals↗
PubMedDate not supplied

Animal and clinical studies of vasopressin effects on learning and memory.

Cognitive deficits of attention deficit disorder in childhood are poorly responsive to presently available medication. Vasopressin derivatives have been reported to enhance learning and memory in animals and in normal humans in controlled studies. This study reports on the effects of vasopressin on learning in rats and in children with learning disorders. Vasopressin treatment three times weekly for 6 weeks in rats appeared to be more effective in enhancing learning and retarding extinction than did vasopressin treatment given only at the beginning of learning and again at the start of extinction. These effects were also shown to be affected by pharmacogenetic factors, since in six inbred mouse strains some showed retarded extinction with vasopressin and others did not. In 17 children with attention and learning disorders, vasopressin derivative was given daily for 10 days and compared with 10 days of placebo treatment in a randomized, crossover, double-blind design. Story memory plus position learning were significantly improved by vasopressin derivative compared with placebo. The same trend of improvement was observed in nine Down's syndrome patients. In 15 other children with attention and learning disorders, a single dose of vasopressin derivative was compared with placebo in a randomized, crossover, double-blind design, and no benefit was found. These parallel animal and human studies suggest that repeated, but not single-dose, vasopressin treatment may benefit childhood learning disorders.

Animals↗
PubMed1977

Preclinical effects: learned behavior.

A review of the previous Marihuana and Health Reports (1971-1975) reveals that an extensive array of experimental procedures and contexts have been used to study the effects of cannabinoids on the performance of learned behavior in animals. These preclinical behavioral experiments have provided a framework for, and guided the design of, subsequent human experimentation. Compared to previous years, only a few experiments pertaining to cannabinoids and learned behavior have appeared during the past two years. By and large these more recent experiments confirm previous findings; no particularly novel procedures have been explored nor have there been dramatically unpredictable results. In part, the decrease in activity in cannabinoid preclinical animal research on learned behavior indicates an increase in human cannabinoid-learning investigations. Several detailed taxonomies of learned behavior are possible. However, for the purposes of the present report, learned behaviors will be categorized into those involving: avoidance learning and aversive control; reinforcement schedules and maze learning; and discrimination learning.

Animals↗
PubMed2000

A model of hippocampally dependent navigation, using the temporal difference learning rule.

This paper presents a model of how hippocampal place cells might be used for spatial navigation in two watermaze tasks: the standard reference memory task and a delayed matching-to-place task. In the reference memory task, the escape platform occupies a single location and rats gradually learn relatively direct paths to the goal over the course of days, in each of which they perform a fixed number of trials. In the delayed matching-to-place task, the escape platform occupies a novel location on each day, and rats gradually acquire one-trial learning, i.e., direct paths on the second trial of each day. The model uses a local, incremental, and statistically efficient connectionist algorithm called temporal difference learning in two distinct components. The first is a reinforcement-based "actor-critic" network that is a general model of classical and instrumental conditioning. In this case, it is applied to navigation, using place cells to provide information about state. By itself, the actor-critic can learn the reference memory task, but this learning is inflexible to changes to the platform location. We argue that one-trial learning in the delayed matching-to-place task demands a goal-independent representation of space. This is provided by the second component of the model: a network that uses temporal difference learning and self-motion information to acquire consistent spatial coordinates in the environment. Each component of the model is necessary at a different stage of the task; the actor-critic provides a way of transferring control to the component that performs best. The model successfully captures gradual acquisition in both tasks, and, in particular, the ultimate development of one-trial learning in the delayed matching-to-place task. Place cells report a form of stable, allocentric information that is well-suited to the various kinds of learning in the model.

Animals↗