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PubMed2002

Chaos in learning a simple two-person game.

We investigate the problem of learning to play the game of rock-paper-scissors. Each player attempts to improve her/his average score by adjusting the frequency of the three possible responses, using reinforcement learning. For the zero sum game the learning process displays Hamiltonian chaos. Thus, the learning trajectory can be simple or complex, depending on initial conditions. We also investigate the non-zero sum case and show that it can give rise to chaotic transients. This is, to our knowledge, the first demonstration of Hamiltonian chaos in learning a basic two-person game, extending earlier findings of chaotic attractors in dissipative systems. As we argue here, chaos provides an important self-consistency condition for determining when players will learn to behave as though they were fully rational. That chaos can occur in learning a simple game indicates one should use caution in assuming real people will learn to play a game according to a Nash equilibrium strategy.

Game Theory↗
PubMed2004

DNA targeting of rhinal cortex D2 receptor protein reversibly blocks learning of cues that predict reward.

When schedules of several operant trials must be successfully completed to obtain a reward, monkeys quickly learn to adjust their behavioral performance by using visual cues that signal how many trials have been completed and how many remain in the current schedule. Bilateral rhinal (perirhinal and entorhinal) cortex ablations irreversibly prevent this learning. Here, we apply a recombinant DNA technique to investigate the role of dopamine D2 receptor in rhinal cortex for this type of learning. Rhinal cortex was injected with a DNA construct that significantly decreased D2 receptor ligand binding and temporarily produced the same profound learning deficit seen after ablation. However, unlike after ablation, the D2 receptor-targeted, DNA-treated monkeys recovered cue-related learning after 11-19 weeks. Injecting a DNA construct that decreased N-methyl-d-aspartate but not D2 receptor ligand binding did not interfere with learning associations between the cues and the schedules. A second D2 receptor-targeted DNA treatment administered after either recovery from a first D2 receptor-targeted DNA treatment (one monkey), after N-methyl-d-aspartate receptor-targeted DNA treatment (two monkeys), or after a vector control treatment (one monkey) also induced a learning deficit of similar duration. These results suggest that the D2 receptor in primate rhinal cortex is essential for learning to relate the visual cues to the schedules. The specificity of the receptor manipulation reported here suggests that this approach could be generalized in this or other brain pathways to relate molecular mechanisms to cognitive functions.

Animals↗
PubMed1999

Perceptual learning in motion discrimination that generalizes across motion directions.

When human subjects discriminate motion directions of two visual stimuli, their discrimination improves with practice. This improved performance has been found to be specific to the practiced directions and does not transfer to new motion directions. Indeed, such stimulus-specific learning has become a trademark finding in almost all perceptual learning studies and has been used to infer the loci of learning in the brain. For example, learning in motion discrimination has been inferred to occur in the visual area MT (medial temporal cortex) of primates, where neurons are selectively tuned to motion directions. However, such motion discrimination task is extremely difficult, as is typical of most perceptual learning tasks. When the difficulty is moderately reduced, learning transfers to new motion directions. This result challenges the idea of using simple visual stimuli to infer the locus of learning in low-level visual processes and suggests that higher-level processing is essential even in "simple" perceptual learning tasks.

Humans↗
PubMed1999

Strategic learning in healthcare organizations.

There is no definitive blueprint for the healthcare organization involved in strategic learning. However, what distinguishes strategic learning institutions is their acknowledgment that they must discover their own paths and solutions rather than blindly follow a detailed strategic mandate from administration. Answers to their most critical implementation and adaptive questions will not flow down ready-made from above, but will be tailored to meet the requirements of their own particular situation. Strategic learning organizations have certain attributes in common in developing their own answers: They continuously experiment rather than seek final solutions. They favor improvisation over forecasts. They formulate new actions rather than defend past ones. They nurture change rather than permanence. They encourage creative conflict rather than tranquillity. They encourage questioning rather than compliance. They expose contradictions rather than hide them (Weick 1977). Most importantly, strategic learning organizations realize that successful strategic change is best undertaken as a process of learning (O'Sullivan 1999). Healthcare organizations can no longer afford the illusion of traditional strategic planning, with its emphasis on bureaucratic controls from the top to the bottom. They must embrace the fundamental truth that most change occurs through processes of learning that occur in many locations simultaneously throughout the organization. The initial step in discovering ways to improve the capability of healthcare organizations is to adapt continuously while fulfilling their mission. Healthcare leaders must create a shared vision of where an institution is heading rather than what the final destination will be, nurture a spirit of experimentation and discovery rather than close supervision and unbending control, and recognize that plans have to be continuously changed and adjusted. To learn means to face the unknown: to recognize that we do not possess all the answers; to concede that we do not always know what to do; to admit that past actions and solutions may no longer be appropriate, in fact may have been the incubators of today's problems; to question basic assumptions long held about running the institution; and to make ourselves vulnerable to the political dynamics prevalent in all organizations. Hospitals and other healthcare organizations must seek to develop and maintain a continuing state of readiness in which everyone in the organization, from front-line clinician to senior management, is poised to act in anticipation of and in response to unforeseen changes in the environment and to learn from their own experiences in confronting the future.

Diffusion of Innovation↗
PubMed2001

The influence of learning style and cognitive ability on recall of names and faces in an older population.

The present study examined whether, for older adults, a verbal or imagery cognitive style is associated with recall of names and faces learned in an experimental condition. Cognitive abilities that are represented in current models of face recognition and name recall were also examined. Those abilities included picture naming, verbal fluency (i.e., naming items within a given category), vocabulary comprehension, visual memory, and the learning of unassociated word pairs. Fifty older adults attempted to learn first and last names of 20 student actors and actresses pictured on videotapes (40 names total). On average, participants learned the most first names, followed by last names, and the fewest full names. The greater the number of responses on a questionnaire associated with an imagery cognitive style, the more the names of faces were correctly identified by participants. There was no significant relationship between a verbal cognitive style and the number of names and faces recalled. As for cognitive abilities, all of the abilities measured--with the exception of vocabulary comprehension--were significantly associated with the number of names and faces learned. A regression analysis indicated that the best predictor of successful name-face learning was the participants' ability to learn and recall 5 unrelated word pairs. When that cognitive measure was deleted from the regression analysis, delayed visual memory and verbal fluency were the next best predictors of the older adults' ability to learn names and faces.

Aged↗
PubMed2006

An innovative outcomes-based medical education program built on adult learning principles.

An innovative medical curriculum at the University of New South Wales (UNSW) has been developed through a highly collaborative process aimed at building faculty ownership and ongoing sustainability. The result is a novel capability-based program that features early clinical experience and small-group teaching, which offers students considerable flexibility and achieves a high degree of alignment between graduate outcomes, learning activities and assessments. Graduate capabilities that focus student learning on generic outcomes are described (critical evaluation, reflection, communication and teamwork) along with traditional outcomes in biomedical science, social aspects, clinical performance and ethics. Each two-year phase promotes a distinctive learning process to support and develop autonomous learning across six years. The approaches emphasize important adult education themes: student autonomy; learning from experience; collaborative learning; and adult teacher-learner relationships. Teaching in each phase draws on stages of the human life cycle to provide an explicit organization for the vertical integration of knowledge and skills. A learning environment that values the social nature of learning is fostered through the program's design and assessment system, which supports interdisciplinary integration and rewards students who exhibit self-direction. Assessment incorporates criterion referencing, interdisciplinary examinations, a balance between continuous and barrier assessments, peer feedback and performance assessments of clinical competence. A portfolio examination in each phase, in which students submit evidence of reflection and achievement for each capability, ensures overall alignment.

Australia↗
PubMed1992

Effects of the model's skill level on observational motor learning.

Observation of a model prior to physical practice often facilitates the acquisition of motor skills. The majority of research studies on observational motor learning has used a skilled model for the demonstration. Recent research, however, suggests that observing an unskilled (learning) model may also be effective. The experiment reported here compared motor skill acquisition following observation of a learning model or a skilled model to the performance of subjects who lacked the benefit of observation. The task was to play a computer tracking game. Subjects were tested in pairs. Observers watched either a skilled or a learning model perform 3 trials. The observers then practiced the game for 3 trials. Observation of another 12 trials was followed by 12 more practice trials. Substantial observational learning was found, as both groups of observers performed better than the learning models after both the 3 initial trials of observation and after 12 more observation trials. However, there were no differences due to observing the skilled or the learning model. These findings are discussed in relation to theoretical issues of observational learning.

Analysis of Variance↗
PubMed2000

Optimizing generalized motor program and parameter learning.

Two experiments examined generalized motor program (GMP) and parameter learning. Experiment 1 examined the effects of bandwidth knowledge of results (KR) about relative timing in constant and variable practice. The purpose was to determine if movement stability created by the bandwidth manipulation is associated with increased GMP learning and if bandwidth KR interacts with constant and variable practice. Participants were asked to depress four keys sequentially, using the same relative timing structure. Constant practice had one absolute timing requirement, whereas variable practice had three different absolute timing requirements. The results indicated that GMP learning was enhanced by constant practice (independent of the bandwidth KR condition) and by bandwidth KR, when variable practice was used. The findings suggest practice conditions (bandwidth KR, constant practice) that increase movement stability during practice enhance GMP learning. Parameter learning (during transfer), however, was enhanced by variable practice. Experiment 2 attempted to determine how constant and variable practice conditions could be combined to enhance both GMP and parameter learning. The results indicated that developing a stable GMP early in practice--by providing learners with constant practice early in practice--and refining parameter learning later in practice--by providing them with variable practice late in practice--were effective for both GMP and parameter learning. This suggests a hierarchy in the development of programmed actions with a stable GMP being a requisite for developing an effective and stable parameter rule.

Adult↗
PubMed2005

Learning preferences of caregivers of asthmatic children.

BACKGROUND: People learn in different ways: visually, aurally, by reading/writing, and kinesthetically. In our clinic, we use color-coded Asthma Action Cards to educate our patients and their caregivers on asthma management. Our teaching is largely aural based, with the cards providing reading and visual stimulation and hands-on practice with devices offering kinesthetic stimulation. OBJECTIVE: We sought to determine the learning styles of the caregivers of our asthmatic children. METHODS: Caregivers in our Asthma/Allergy Clinic completed the Visual-Aural-Read/Write-Kinesthetic (VARK) questionnaire anonymously, and the responses were evaluated on the basis of previously validated scoring instructions. RESULTS: Analysis of 98 respondents showed that 42% had a single learning modality preference, and the remaining 58% were multimodal learners. Of those who reported a single mode of learning, 61% preferred kinesthetic, 27% preferred reading/writing, and less than 1% each preferred aural or visual stimuli. Of all 98 caregivers, 82% included kinesthetic as a learning preference, 59% included read/write, 50% included aural, and 41% included visual. CONCLUSION: The majority of caregivers preferred the kinesthetic learning method, whether as a single learning preference or in combination with other approaches. Incorporating kinesthetic methods of learning, such as role plays and problem-solving case scenarios, into standardized asthma education curricula may be beneficial to patients and families in terms of understanding and using their regimen.

Asthma↗
PubMed2006

The treatment of anomia using errorless learning.

In the contemporary literature, errorless learning is thought to have benefits over more traditional trial-and-error methods. The most prominent investigations of errorless learning are those designed for rehabilitation of severe memory impairments, including numerous demonstrations of effective amelioration of word-finding difficulties (Baddeley & Wilson, 1994; Clare, Wilson, Breen, & Hodges, 1999; Clare et al., 2000; Evans et al., 2000). Despite this, there are very few reports on the application of purely errorless learning to people with aphasia (Fillingham, Hodgson, Sage, & Lambon Ralph, 2003). The aim of this study was to compare directly the efficacy of errorless and errorful learning in a case series of 11 aphasic people with pronounced word-finding difficulties. Previous studies of errorless learning and, more recently, studies of rehabilitation have suggested that cognition is an important factor for determining outcome (Helm-Estabrooks, 2002; Robertson & Murre, 1999). Therefore, a thorough language and neuropsychological assessment battery was completed with each participant. Naming therapy was carried out to contrast errorless and errorful therapy in a case series analysis. Errorless learning proved to be as effective as the more traditional, errorful approach in the majority of cases in terms of both immediate improvement and at follow up assessment. Without exception, the patients preferred the errorless learning therapy. Strikingly, it was found that language skill did not predict therapy outcome. Participants who responded better overall, had better recognition memory, executive/problem solving skills and monitoring ability. This replicates recent findings that frontal executive skills are crucial for rehabilitation (Robertson & Murre, 1999). Also, participants who did better at errorful treatment were those with the best working and recall memory, and attention. It is probable that these factors are essential cognitive components for providing effective monitoring and feedback systems to a more general learning mechanism.

Adult↗
PubMed2005

Developing an interprofessional learning culture in primary care.

This paper discusses the concept of interprofessional learning based on empirical data from an evaluation of an interprofessional learning project that was set in a British primary health care centre. A process evaluation methodology was chosen to collect the data using semi-structured interviews and focus groups with stakeholders and staff to gather their experiences and views of the project and documentary data from records written over the lifetime of the project. The paper argues that an interprofessional learning culture requires time to become embedded in everyday practice and to achieve such a culture, shared values, aims and clear communication are essential. The data suggest that there is a need to recognize responsibility for one's own learning as individuals as well as learning as teams of work colleagues if interprofessional learning is to be successful. However, even when these pre-requisites of interprofessional learning are agreed and acknowledged openly in the workplace, participants in the development of a learning culture need to recognize that there are structural controls which influence and constrain such developments which are external to participants and beyond their immediate control.

Community Health Nursing↗
PubMed2003

Student generated learning objectives: extent of congruence with faculty set objectives and factors influencing their generation.

CONTEXT: A problem-based learning strategy is used for curriculum planning and implementation at the Arabian Gulf University, Bahrain. Problems are constructed in a way that faculty-set objectives are expected to be identified by students during tutorials. Students in small groups, along with a tutor functioning as a facilitator, identify learning issues and define their learning objectives. PURPOSE: We compared objectives identified by student groups with faculty-set objectives to determine extent of congruence, and identified factors that influenced students' ability at identifying faculty-set objectives. METHOD: Male and female students were segregated and randomly grouped. A faculty tutor was allocated for each group. This study was based on 13 problems given to entry-level medical students. Pooled objectives of these problems were classified into four categories: structural, functional, clinical and psychosocial. Univariate analysis of variance was used for comparison, and a p > 0.05 was considered significant. RESULTS: The mean of overall objectives generated by the students was 54.2%, for each problem. Students identified psychosocial learning objectives more readily than structural ones. Female students identified more psychosocial objectives, whereas male students identified more of structural objectives. Tutor characteristics such as medical/non-medical background, and the years of teaching were correlated with categories of learning issues identified. CONCLUSION: Students identify part of the faculty-set learning objectives during tutorials with a faculty tutor acting as a facilitator. Students' gender influences types of learning issues identified. Content expertise of tutors does not influence identification of learning needs by students.

Bahrain↗
PubMed2003

Age-related decline in spatial learning and memory: attenuation by captopril.

Spontaneously hypertensive rats (SHR) compared to normotensive rats display an accelerated decline in spatial learning and memory. However, few studies have systematically examined the independent contribution of hypertension vs. other age-related mechanisms to this decline. The present study uses a repeated acquisition water maze task to test the hypothesis that hypertension and/or the presence of angiotensin II can accelerate the age-related decrease of spatial learning and memory in rats. We have previously shown that both SHR and Wistar-Kyoto rats (WKY) display age-related decreases in spatial learning and memory; however, the rate of decline differs between the strains. The present results demonstrate that compared to young rats of the same strain, learning and memory in SHR declines significantly already at 12 months of age, and at 24 months of age both SHR and WKY rats are severely impaired in the water maze task. Lifetime treatment of either SHR or WKY with the antihypertensive drug captopril [an angiotensin converting enzyme (ACE) inhibitor] significantly attenuates the age-related impairment in learning and memory. In contrast, chronic treatment of SHR with captopril from 6 months of age only modestly decreases the decline in learning and memory. Whereas lifetime treatment with the vasodilator drug hydralazine also reduces arterial pressure in SHR, this treatment does not significantly preserve learning in 24-month-old SHR. Together, the data suggest captopril can delay the decline in spatial learning and memory in both aging SHR and WKY. Further, the results indicate that the memory enhancing effects of captopril are not primarily the due to the ability of captopril to lower blood pressure.

Aging↗
PubMed2026

NanoSSL: attention mechanism-based self-supervised learning method for protein identification using nanopores.

MOTIVATION: Nanopores are cutting-edge interdisciplinary tools that can analyze biomolecules at the single-molecule level for many applications, e.g. DNA sequencing. Efforts are underway to extend nanopores to proteomics, including the development of machine learning algorithms for protein sequencing and identification. However, single-molecule data are intrinsically noisy and hard to process. Moreover, the development and performance of machine learning for nanopore is jeopardized by data scarcity. Self-supervised learning is an emerging method that may yield advantages in nanopore scenarios. RESULTS: We propose and experimentally validate Nanopore analysis using Self-Supervised Learning (NanoSSL), a generative self-supervised learning framework based on attention mechanisms for the identification of protein signals from nanopores. Leveraging a two-step approach consisting of self-supervised pre-training and supervised fine-tuning, NanoSSL learns useful feature representations from empirical data to facilitate downstream classification tasks. Inspired by the concept of fragmentation in conventional protein sequencing technologies, during pretraining each translocation event is split into multiple non-overlapping fragments of equal size, some of which are randomly masked and reconstructed using a masked autoencoder. Learning the feature representations of the reconstructed nanopore events facilitates molecular identification in fine-tuning. In this study, we retested a publicly available nanopore multiplexed protein sensing dataset for model iteration, and subsequently measured Alzheimer's disease biomarker Aβ1-42 using homemade solid-state nanopores. Empirical results indicated NanoSSL achieved an unprecedented performance across four metrics: accuracy, precision, recall, and F1 score, when classifying two mutated Aβ1-42, E22G and G37R. The self-supervised learning and attention mechanism were verified as the source of performance gains. AVAILABILITY AND IMPLEMENTATION: The main program is available at https://doi.org/10.5281/zenodo.17172822.

Nanopores↗
PubMed1999

Callosal and cortical contribution to procedural learning.

Acallosal and callosotomized subjects usually show impairments on tasks requiring bilateral interdependent motor control. However, few studies have assessed the ability of these subjects to learn a skill that requires the simultaneous contribution of each hemisphere in its acquisition. The present study examined whether acallosal and callosotomized subjects could learn a visuomotor skill that involved a motor control from either both or a single hemisphere. Eleven adult patients, six acallosal and five callosotomized, participated in this study. Seven of these patients had epileptic foci located in the frontal and/or temporal areas and one of the acallosal patients showed bilateral prefrontal atrophy following surgical removal of an orbitofrontal cyst. The performance of the experimental subjects was compared with that of 11 matched control subjects, on a modified version of a serial reaction time task developed by Nissen and Bullemer (Cogn Psychol 1987; 19: 1-32). This skill acquisition task involved bimanual or unimanual key-pressing responses to a sequence of 10 visual stimuli that was repeated 160 times. A declarative memory task was then performed to assess explicit knowledge of the sequence. None of the experimental subjects learned the task in the bimanual condition. Patients with frontal epileptic foci or orbitofrontal damage also failed to learn the task in the unimanual condition when they were using the hand contralateral to the damaged hemisphere. All other subjects, including the acallosal and callosotomized patients with temporal foci, learned the visuomotor skill as well as their controls in the unimanual condition. In spite of the absence of transfer and interhemispheric integration of procedural learning, some of the acallosal and callosotomized patients were able to learn the sequence explicitly. These findings indicate that the corpus callosum and the frontal cortical areas are important for procedural learning of a visuomotor skill. They also confirm the dissociation described by Squire (Science 1986; 232: 1612-9 and J Cogn Neurosci 1992; 4: 232-43) between the declarative and procedural memory systems and extend this dissociation to processes involving simultaneous bihemispheric co-operation.

Adult↗
PubMed2001

Characterizing the neural mechanisms of skill learning and repetition priming: evidence from mirror reading.

The changes in brain activity related to skill learning and repetition priming in a mirror-reading task were examined using functional MRI. Subjects exhibited significant learning across five training sessions and this learning generalized significantly to different spatial transformations (inverted-mirror reversed text and normal letters spelled backwards). Mirror reading, compared with reading normal text, was associated with extensive activation in occipital, temporal, parietal and frontal regions. Learning to read mirror-reversed (MR) text was associated with increased activation in left inferior temporal, striatal, left inferior prefrontal and right cerebellar regions and with decreased activity in the left hippocampus and left cerebellum. Short-term repetition priming was associated with reduced activity in many of the regions active during mirror reading and extensive item-specific practice (long-term repetition priming) resulted in a virtual elimination of activity in those regions. Short- and long-term repetition priming thus appeared to rely upon common neural mechanisms. Nearly all of the regions exhibiting significant learning-related changes also exhibited increased repetition priming effects, suggesting common neural substrates for priming and skill learning in this task. Comparison of MR items with other spatially transformed typographies showed that the learning-related changes were general to all of the spatial transformations. The results confirm the importance of striatofrontal neural networks for the acquisition of skills, and suggest that skill learning and repetition priming may have common substrates within a particular task.

Adult↗
PubMed1983

Lateral dominance in children with learning disabilities.

The purpose of the study was to investigate the occurrence of lateral dominance problems in a sample of children with learning disabilities. Ninety-one children (62 boys, 29 girls) who attended a school for children with learning disabilities were selected for the study. The Harris tests of lateral dominance were administered individually, and the children were rated as having right, left, or mixed dominance for hand, eye, and foot. When compared with normative data on dominance in children, the results showed that the occurrence of mixed hand dominance was no more frequent, the occurrence of mixed eye dominance was less frequent, and the occurrence of mixed foot dominance was more frequent in the children with learning disabilities. Results also showed that the occurrence of mixed and crossed eye-hand dominance was significantly different in children with learning disabilities when compared with children without learning disabilities. However, the occurrence of mixed eye-hand dominance was found to be significantly greater in children without learning disabilities than in learning disabled children. Age and sex were not found to affect the occurrence of lateral dominance problems in children with learning disabilities.

Child↗
PubMed1998

Desflurane and the nonimmobilizer 1,2-dichlorohexafluorocyclobutane suppress learning by a mechanism independent of the level of unconditioned stimulation.

UNLABELLED: We previously demonstrated that anesthetics and non-immobilizers suppress learning and memory in rats. In the training portion of the test, rats received a light plus a footshock and learned to associate the two, as evidenced by subsequent potentiation of the response (jumping) to light plus a noise (fear-potentiated startle). However, anesthetics and nonimmobilizers also decreased the response of animals receiving footshocks during training, which suggests that the reduction in fear-potentiated startle might reflect analgesia, rather than an impairment of learning and memory. Furthermore, although we previously demonstrated that the nonimmobilizer 2,3-dichlorohexafluorocyclobutane (2N) could completely abolish learning, we did not demonstrate the minimal dose required. In the present study, we eliminated analgesia as a confounding factor by training rats breathing desflurane and 2N with footshock intensities that produced responses at least equal to those produced in control animals. Both desflurane and 2N suppressed learning at 0.2 times the minimum alveolar anesthetic concentration (MAC) or the MAC predicted from lipid solubility, despite the increased footshock intensity. This partial pressure of desflurane equals that previously shown to suppress learning at lower footshock intensities. We conclude that suppression of learning and memory by desflurane and 2N does not result from decreased sensitivity to the unconditioned stimulus (the footshock) and that the potency of 2N is consistent with its lipophilicity. IMPLICATIONS: General anesthesia eliminates recall of intraoperative events, including pain. Using an animal model, we refuted the hypothesis that lack of recall results from the analgesia (i.e., the reduced response to painful stimuli produced by inhaled drugs) rather than from a direct effect on learning.

Administration, Inhalation↗