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Results for “Informal learning”

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PubMed1987

The impairment of retention induced by pentylenetetrazol in mice may be mediated by a release of opioid peptides in the brain.

Pentylenetetrazol (PTZ, 45 mg/kg, ip) impaired retention of a one-trial step-through inhibitory avoidance task when injected into male Swiss mice 10 min after training, as indicated by retention performance 48 h later. The amnestic effect of PTZ was prevented by naltrexone (0.01 or 0.10 mg/kg, ip) administered after training, but prior to PTZ-treatment. On the contrary, neither naltrexone methyl bromide (0.01, 0.10, or 10.0 mg/kg, ip), a quaternarium analog of naltrexone, nor MR2266 (0.01 or 0.10 mg/kg, ip), a putative kappa opiate receptor antagonist, modified the behavioral effects of PTZ. On the other hand, the body seizures produced by PTZ were unaffected by any of the three opiate receptor antagonists that were given before the convulsant. Taken together, these results suggest that the effects of PTZ on retention are mediated, at least in part, by opioid peptides of central origin, and rules out a possible participation of opioid peptides derived from prodynorphin-precursor molecule. Administration of beta-endorphin (0.01 or 0.10 microgram/kg, ip) 10 min prior to testing attenuate the retrograde amnesia caused by PTZ. The effect of beta-endorphin was prevented by the simultaneous administration of naltrexone (0.10 mg/kg, ip) prior to testing. Naltrexone has no effect of its own upon retrieval. These results suggest that the impairment of retention induced by PTZ is probably due, at least in part, to a release of opioid peptides in the brain during the post-training period. PTZ given after training do not affect consolidation or memory storage, as mice thus treated may retrieve the learned information when they are submitted to an appropriate neurohumoral and/or hormonal state in the test session, that is, beta-endorphin injection. Therefore, the action of PTZ would be primarily at the level of the mechanism that make stored information available for late retrieval.

Animals↗

PubMed1990

Behavioral effects of MK-801 in the rat.

Several experiments were conducted to study the effects of the noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist, MK-801, on learning and memory in the rat. Rats displayed impaired performance on several sensorimotor tests and appeared grossly intoxicated when treated IP with 0.2 mg/kg MK-801, but not when treated with lower doses (0.05 or 0.1 mg/kg). Postacquisition performance on two spatial learning tasks involving working memory protocols (reinforced alternation and radial arm maze) was impaired by MK-801 at intoxicating doses (greater than or equal to 0.2 mg/kg) but not at lower doses (0.05 or 0.1 mg/kg). Using a position habit reversal task, we found that rats could learn to reverse a position habit while under the influence of a nonintoxicating dose of MK-801 (0.1 mg/kg), but when tested on the following day performed as if they did not recall what they had learned. Thus, acute administration of a nonintoxicating dose of MK-801 disrupts the retention of new information learned under the influence of the drug but does not interfere with the performance of tasks that are well learned before the drug is administered. Whether the performance deficits on the spatial learning tasks observed only following intoxicating doses of MK-801 reflect an effect on memory is not clear.

Animals↗

PubMed2004

Disrupting feedback processing interferes with rule-based but not information-integration category learning.

The effect of a sequentially presented memory scanning task on rule-based and information-integration category learning was investigated. On each trial in the short feedback-processing time condition, memory scanning immediately followed categorization. On each trial in the long feedback-processing time condition, categorization was followed by a 2.5-sec delay and then memory scanning. In the control condition, no memory scanning was required. Rule-based category learning was significantly worse in the short feedback-processing time condition than in the long feedback-processing time condition or control condition, whereas information-integration category learning was equivalent across conditions. In the rule-based condition, a smaller proportion of observers learned the task in the short feedback-processing time condition, and those who learned took longer to reach the performance criterion than did those in the long feedback-processing time or control condition. No differences were observed in the information integration task. These results provide support for a multiple-systems approach to category learning and argue against the validity of single-system approaches.

Feedback↗

PubMed2002

Regulated transcription of the immediate-early gene Zif268: mechanisms and gene dosage-dependent function in synaptic plasticity and memory formation.

The immediate-early gene Zif268 is a member of the Egr family of inducible transcription factors. Data from gene expression studies have suggested that this gene may play a critical role in initial triggering of the genetic machinery that has long been considered a necessary mechanism for maintenance of the later phases of LTP and also for the consolidation or stabilization of long-lasting memories. Until recently, however, the data supporting this assumption have been based primarily on circumstantial evidence, with no direct evidence to suggest that Zif268 is required for long-lasting synaptic plasticity and memory. In this report, we review our own data using Zif268 mutant mice; we show that although the early phase of dentate gyrus LTP is normal in these mice, the later phases are not present, and the ability of the mice to maintain learned information over a 24-h period is deficient. In addition, we present new information showing a task-dependent gene dosage effect in Zif268 heterozygous mice. We show that spatial learning is particularly sensitive to reduced levels of Zif268, as one-half of the complement of Zif268 in heterozygous mice is insufficient to maintain spatial long-term memories.

Animals↗

PubMed2004

Recovery from brain injury in animals: relative efficacy of environmental enrichment, physical exercise or formal training (1990-2002).

In the 1960s, it was shown for the first time that enriched housing enhances functional recovery after brain damage. During the 1970s and 1980s, many findings similar to this initial one have been reported, enlarging greatly its generality. Over the last 13 years, many different kinds of brain damage were modelled in animals or even directly studied in humans. Overall, these recent studies corroborated earlier findings, although occasional exceptions were reported. Other critical data, obtained mainly in intact animals, showed that enriched housing increases neurogenesis in the adult hippocampus. Recent evidence that this neurogenesis is involved in hippocampal-dependent learning supports the original interpretation of the enrichment effects as being the result of an accumulation of informal learning experiences (e.g., [. Heredity, environment, brain biochemistry, and learning. In: Current Trends in Psychological Theory. University of Pittsburgh Press, Pittsburgh, pp. 87-110;. Brain changes in response to experience. Sci. Am. 226, 22-29]). Other components of enriched environment, such as physical exercise, may have additive effects with those of training. The comparison of the relative effectiveness of enriched experience, of physical exercise and of training on structural and/or functional assessments of recovery, shows that training/learning is generally more effective than physical exercise and that enriched experience is a more potent therapy than either of these two other treatments. The combination of enriched experience with some other neurosurgical and/or neuropharmacological treatments may further improve its therapeutic effectiveness. Finally, other recent reports emphasize that the treatment parameters may be changed in order to approximate clinical/rehabilitation conditions and, nevertheless, remain effective.

Animals↗

PubMed1994

Age-related effects of the nicotinic antagonist mecamylamine on cognition and behavior.

Studies of the neurochemical pathology of Alzheimer's disease and Parkinson's disease reveal a severe and specific loss of central nicotinic cholinergic receptors. We have investigated the functional significance of this finding for cognitive functioning by studying the effects of the centrally active nicotinic antagonist mecamylamine. Single oral doses of mecamylamine were administered to 12 healthy young males and 15 healthy elderly subjects in doses of 5, 10, and 20 mg in a placebo-controlled, double-blind study. In both groups, the 20-mg dose caused a significant increase in errors in the learning condition of the Repeated Acquisition Task, producing a slower acquisition curve. There was no effect of drug on the performance component (retrieval of previously learned information). However, elderly subjects showed enhanced sensitivity to mecamylamine, with 10-mg dose producing significant impairment of learning not seen in the young normals. On a recognition memory task, there was an age-associated shift in response bias, with the elderly subjects becoming more liberal with increasing dose. Reaction-time measures suggested a dose-related slowing of reaction time on several tasks. Behavioral effects were minimal and physiologic effects were consistent with dose-related ganglionic blockade. These results indicate that acute blockade of nicotinic receptor function can produce measurable and significant cognitive impairment similar to some deficits seen in dementing illnesses, and that there is an age-related increase in sensitivity to nicotinic blockade.

Adult↗

PubMed1998

[Practice and research of forensic medicine learned from the dead].

Practice and Research of Forensic Medicine Learned from the Dead' is presented by looking back my 29 years' carrier as a forensic pathologist. After joining in Department of Forensic Medicine, Kumamoto University in 1969, I had spent several happy years with studying on postmortem corneal clouding. Soon I began to have doubts on a purpose of forensic autopsy in my department then, which seemed to be only to/under the police. I spent one year at Department of Forensic Medicine, Leeds University in England in 1979-1980 and experienced Forensic Medicine not only for the police but also for the society in general. Visiting several university departments in Europa at that time, I felt confident that Forensic Medicine is one special field of medical sciences and will be worth a subject to devote my life. Clinical Forensic Medicine is one field of forensic medicine. Its importance has been recognized in the society by increasing numbers of felonious crimes and campaigns of human rights throughout the world. In 1996, the 4th International Conference of World Police Medical Officers in Clinical Forensic Medicine was ended in a great success in Kumamoto, Japan. Now evaluation and development of Clinical Forensic Medicine are very essential for both forensic pathologists and clinicians to serve for the society. My own activities of teaching traffic safety and preventing child abuse and neglect were cited as examples of 'Practice of Forensic Medicine Learned from the Dead'. Studies on differentiation of postmortem discoloration and antemortem bleeding by glycophorin A or erythrocyte membranes and an international joint research project with Tanzania on neuropathology of AIDS were examples of 'Research of Forensic Medicine Learned from the Dead'. It is an important mission for a forensic pathologist to work for/with the police to solve crimes by hearing a voice of the dead on an autopsy table. Through friendship with foreign colleagues, however, I have learned much about what should be a forensic pathologist and have been inspired with a phrase, 'The information learned from studying the dead could be used to help the living.' by Dr. T.A. Gonzales of the Chief Medical Examiner's Office of New York. Because social activities of preventing crimes and accidents are very much important matters indeed, every forensic pathologist must devote his/her forensic practice and research to achieve a peaceful end of life for every citizen, I believe.

Accidents, Traffic↗

PubMed2001

Learning and change among leaders of a professional nursing association.

This is a report of the results of a qualitative research study that investigated the informal learning and changes experienced by 20 members of an exemplary chapter of critical care nurses as they advanced from being new members to becoming officers and board members. Qualitative research methods were used that included analysis of critical incidents, documents, and individual interviews. Methods used, results of the study, and conclusions and recommendations are discussed.

Anecdotes as Topic↗

PubMed1975

Pattern learning and the control of behaviour by all-inhibitory neural network hierarchies.

An all-inhibitory network which learns by selective disconnection of synapses is described. This is similar to an 'associative net'; however, it is simpler in that its neurons do not need to perform arithmetical operations, and the net does not require additional threshold modulating neurons in order to cope with input patterns which are incomplete, or of differing sizes. This fundamental simplicity permits a greater variety and density of connections. These can multiply the capacity of the nets to learn complex sequences of patterns without being saturated. An "all-connected" net is described which has the holograph-like capacity to reconstruct the whole of an input pattern from part patterns without involving delays or threshold devices. All of these inhibitory nets can construct themselves by means of simple random growth processes, without incurring any loss of learning capacity of holographic properties. Similarly, synapses can be allowed to potentiate with use, so that reaction times are progressively reduced by practice, without any reduction in the quality of the performance. Inhibitory connections between arrays can give patterns in one array control over the allocation of channels in which lower arrays store learned information. A description is given of a model, decentralised, inhibitory hierarchy consisting of inter-connected arrays which can learn to execute goal-directed TOTE-type programs of behaviour by means of a simple 'putting-through' procedure.

Axons↗

PubMed1983

Effects of serotonin on memory impairments produced by ethanol.

Subjects treated with low or high doses of ethanol demonstrated impaired memory, particularly in tests involving the recall of poorly learned information. Zimelidine, an inhibitor of serotonin reuptake, reversed this ethanol-induced impairment. The serotonin neurotransmitter system may mediate learning and memory in humans and may determine some of the effects of alcohol on higher mental functions.

Adult↗

PubMed1998

Effects of map orientation during learning on airport identification.

BACKGROUND: If an observer first learns to recognize an object in a specific orientation, a significant increase in processing time usually occurs when the object is subsequently seen in a different orientation; this phenomenon is called the "misorientation effect." The present study examines how quickly and how accurately human observers discriminate between airport maps that are viewed in orientations other than those in which they were initially learned. METHOD: Participants were trained to discriminate between two navigation maps that were seen in only one orientation; they subsequently were tested with maps and aerial photographs of the same airports that were presented in various orientations. RESULTS AND CONCLUSIONS: There were three principal findings: a) discriminative responses to maps of airports were most rapid when the maps were seen in the same orientation as that in which they were initially learned; b) a significant reduction in reaction time (RT) occurred with repeated presentations of the misoriented stimuli; and c) information learned from navigation maps was not sufficient for all observers to recognize aerial photographs of the same airports.

Adult↗

PubMed2006

Student perceptions of the effectiveness of education in the responsible conduct of research.

Responsible conduct of research (RCR) courses are widely taught, but little is known about the purposes or effectiveness of such courses. As one way to assess the purposes of these courses, students were surveyed about their perspectives after recent completion of one of eleven different research ethics courses at ten different institutions. Participants (undergraduate and graduate students, post-doctoral fellows and faculty, staff and researchers) enrolled in RCR courses in spring and fall of 2003 received a voluntary, anonymous survey from their instructors at the completion of the course. Responses were received from 268 participants. Seventy-seven percent of open-ended responses listed specific kinds of information learned; only a few respondents talked about changes in skills or attitudes. The perception that courses did more to provide information than to foster skills or attitudes was verified in quantitative responses (P<0.0001). Over 75% of the respondents specifically noted that courses were useful in preparing them to recognize, avoid, and respond to research misconduct. The two principal findings of this multi-institutional study are that respondents reported: (1) a wide variety of positive outcomes for research ethics courses, but that (2) the impact on knowledge was greater than that for changes in skills or attitudes.

Attitude↗

PubMed1991

Vascular smooth muscle contraction and relaxation: pathways and chemical modulation.

The purpose of this review has been to summarize the information learned in the past few years regarding the mechanisms responsible for smooth muscle contraction and relaxation and to relate this information to the vasoconstrictor and vasodilator agents used by the interventional radiologist. Because this review can only provide an overview of what is known about these processes, the reader is directed to the references cited below. This reference list contains review articles that will provide in-depth information about the topics presented herein.

Endothelium, Vascular↗

PubMed2003

Experimental evidence for spatial learning in cuttlefish (Sepia officinalis).

Laboratory mazes were used to study spatial-learning capabilities in cuttlefish (Sepia offcinalis), using escape for reinforcement. In preliminary observations, cuttlefish in an artificial pond moved actively around the environment and appeared to learn about features of their environment. In laboratory experiments, cuttlefish exited a simple alley maze more quickly with experience and retained the learned information. Similar improvement was not found in open-field mazes or T mazes, perhaps because of motor problems. Cuttlefish learned to exit a maze that required them to find openings in a vertical wall. The wall maze was modified to an arena, and simultaneous discrimination learning and reversal learning were demonstrated. These experiments indicate that cuttlefish improve performance over serial reversals of a simultaneous, visual-spatial discrimination problem.

Animals↗

PubMed2004

Adult age differences in self-regulated learning from reading sentences.

We examined age differences in the heuristic used to allocate effort in learning information from sentences. Younger and older adults read and reread sentences varying in propositional density for recall, making judgments of learning before producing recall. The allocation of effort in rereading items that were less well learned on the first reading was optimized for sentences of intermediate complexity, especially for older adults. These data support a model of self-regulated learning in which readers reduce the discrepancy between current and optimal states of learning. However, self-regulation, which may be procedure based or rely on an implicit representation of the current state of learning, may be particularly efficient for older adults within a region of proximal learning.

Adult↗

PubMed1997

Self-directed patient education in soft-tissue rehabilitation: rationale and analysis of a pilot project.

OBJECTIVES: To determine the compliance level and topic choice selection frequency of rehabilitation patients in a self-directed education program offered in conjunction with a rehabilitation exercise program. DESIGN: Descriptive study. SETTING: Soft-tissue injury rehabilitation clinic located within a chiropractic college. SUBJECTS: Twenty-four rehabilitation patients with injured spines who were enrolled in a daily in-clinic program. OUTCOME MEASURES: Data was collected from patient log-book pages, which recorded frequency of use, topic, medium and personal satisfaction for each selected resource. Clinic attendance data was collected by the clinical staff. RESULTS: Eighty-one percent (81%) of the patient group voluntarily used the learning center. Average frequency of use was approximately one visit per patient per week. Of the 13 subject areas included in the resource center collection, back injury care (30), nutrition (22) and fitness/exercise (14) received the most use. Patient satisfaction with the resources' value/interest averaged 78.4%. CONCLUSIONS: Most (81%) patients in this group were willing to spend some of their own time learning information that they thought was important. The results may allow for patient education program designs that put more responsibility for learning with the patient and allow for more efficient clinician time allocation.

Adult↗

PubMed2006

Reasons for post registration learning: impact of the learning experience.

This exploratory study is the second stage of a multi-method approach to explore some of the reasons why registered nurses take part in formal and informal learning and higher education. Also under exploration is the extent to which their various learning experiences met their expectations. The sample consists of 25 registered nurses, randomly selected from a population (N=162) of 1st and 2nd Level nurses employed in public and private clinical settings, who have taken part in continuing education to obtain a Diploma or a Degree in Nursing. The data gathering was achieved by three focus group interviews. Formal learning included mandatory and non-mandatory in house teaching. Mandatory input was regarded as a self-protection measure by the employer, not related to personal development and with no perceived benefit on client care. Regarding the achievement of additional clinical competences, the overwhelming reason is to improve client care, although the motives of the employer and medical staff are viewed with some suspicion as a measure to saving doctors' time. Higher education pursuits appears to be triggered by a perceived need to increase the participants' level of existing knowledge in line with that of current students on placement, but adjustment to adult life transition period also appear to be an influencing factor. In terms of learning experiences, the relevance and quality of mandatory sessions came under criticism, whilst a measure of surprise was expressed at the unexpected benefits, at a personal and a professional level, gained by taking part in academic learning.

Adult↗

PubMed1997

Shoaling generates social learning of foraging information in guppies

Two experimental studies are reported which investigate the social learning of foraging information in guppies, Poecilia reticulataIn both cases, untrained adult female guppies swam with trained conspecifics to feed, and in the process learned a route to a food source. In experiment 1, subjects were given 5 days experience swimming with demonstrator fish trained to take one of two equivalent routes to food. When tested alone, subjects preferentially used the route of their demonstrators. Experiment 2 investigated whether this social learning could mediate the stable transmission of route preferences among small populations of fish. This experiment used a transmission chain design, in which fish in small founder populations were trained to take one of the two routes, with founder members gradually replaced by untrained conspecifics. Three days after all founder members had been removed, populations of untrained fish still maintained strong preferences for the routes of their founders. The results suggest that the tendency to shoal may facilitate a simple form of guided social learning, which allows guppies to learn about their local environments. They also imply that selectively neutral behavioural alternatives may be maintained as traditions in aggregated animal populations by very simple social mechanisms. The transmission chain method may be particularly useful for studying social species, such as the guppy, that do not respond well to isolation testing.

Journal Article↗