PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “GENERALIZATION LEARNING”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources

Generalized relevance learning vector quantization.

We propose a new scheme for enlarging generalized learning vector quantization (GLVQ) with weighting factors for the input dimensions. The factors allow an appropriate scaling of the input dimensions according to their relevance. They are adapted automatically during training according to the specific classification task whereby training can be interpreted as stochastic gradient descent on an appropriate error function. This method leads to a more powerful classifier and to an adaptive metric with little extra cost compared to standard GLVQ. Moreover, the size of the weighting factors indicates the relevance of the input dimensions. This proposes a scheme for automatically pruning irrelevant input dimensions. The algorithm is verified on artificial data sets and the iris data from the UCI repository. Afterwards, the method is compared to several well known algorithms which determine the intrinsic data dimension on real world satellite image data.

Algorithms↗

Learning and generalization with Minimerror, a temperature-dependent learning algorithm.

We study the numerical performances of Minimerror, a recently introduced learning algorithm for the perceptron that has analytically been shown to be optimal both on learning linearly and nonlinearly separable functions. We present its implementation on learning linearly separable boolean functions. Numerical results are in excellent agreement with the theoretical predictions.

Algorithms↗

Perceptual-motor sequence learning of general regularities and specific sequences.

Participants viewed digit strings and typed them on a computer keyboard. When they used the same key configuration across training and test, they typed test strings that adhered to the same sequence rule as training strings faster than test strings that adhered to the opposite rule (general-regularity [GR] learning), and they typed test strings that were processed repeatedly during training faster than test strings that were not (specific-sequence [SS] learning). However, when they used different key configurations at training and at test, GR learning, but not SS learning, was observed. Conversely, when they did not type but spoke the strings aloud during training, SS learning, but not GR learning, was observed. Results suggest that in addition to declarative memory for specific sequences, relatively independent subsystems underlie procedural learning of perceptual-motor sequence components (producing GR effects) and sequence wholes (producing SS effects).

Female↗

New semantic learning and generalization in a patient with amnesia.

New learning of semantic information is impaired in amnesia. Several reports have demonstrated that "errorless" learning techniques have allowed patients with amnesia to acquire at least some form of new semantic information, although this information appears to be relatively inflexible. Using insights and principles from connectionist modeling of cortical and medial temporal lobe memory systems, the authors describe why errorless learning procedures act as a poor proxy for the medial temporal lobe, suggesting that they artificially eliminate the variability that defines semantic information. The authors trained a patient with severe amnesia on new semantic sentences both with and without variance and then tested him on both repeated and related novel sentences to assess generalization. He successfully learned new semantic information in both conditions but demonstrated better generalization of semantic concepts following training with variance.

Aged↗

Human learning during general anaesthesia and surgery.

To determine if learning occurs during general anaesthesia, 72 women undergoing surgery were given postoperative implicit memory tests in which performance could be influenced by auditory information presented during general anaesthesia. Two methods of anaesthesia were used: nitrous oxide and opioids (n = 24) or nitrous oxide and isoflurane (1, 1.3 and 1.5 MAC for n = 12, 24 and 12, respectively). Three tests showed some retention, apparently unconscious, of information presented during anaesthesia: in Behavioural Suggestions tests, patients who were instructed during anaesthesia to touch a particular body part (ear or nose) during later questioning touched the "correct" (suggested) body part longer than the "incorrect" (not suggested) body part during a postoperative interview on the day of surgery (means 2.5 vs 0.2 s); in World Completion tests, patients shown a page containing the first three letters of words and asked to give words beginning with those letters gave more words from a list that had been played during anaesthesia than from a list not played (means 0.48 vs 0.27 words); in Nonsense Word tests, patients who were played different nonsense words between two and 16 times during anaesthesia preferred and guessed more accurately those that had been played most often (16 times) relative to those played less often in subsequent preference and recognition tests (means 56% vs 46% for preference and 62% vs 48% for recognition), while showing no such patterns in additional control tests. Learning did not vary with the method of anaesthesia, as might have been expected if learning was a monotonic function of brain depression. Some information processing functions of the brain evidently continue to function during adequate general anaesthesia.

Adult↗

Independent learning among general practice trainees: an initial survey.

Self-directed learning is a natural way for adults to learn. Vocational training for general practice is a preparation for unsupervised clinical work that will be supported, in the main, by continuing medical education. This study uses the Self-Directed Learning Readiness Scale to investigate factors influencing readiness for such learning among a sample of general practice trainees. Three principal factors emerged from analysis: enjoyment and enthusiasm for learning; a positive self-concept as a learner and a factor suggesting the possibility of a 'reproducing' orientation to learning. These factors may reflect approaches to learning in general rather than these adopted for professional learning, but offer helpful pointers for the development of both vocational training and of continuing medical education.

Attitude of Health Personnel↗

How do General Practitioners learn of their patient's deaths?

OBJECTIVES: To investigate the methods by which General Practitioners learn, or do not learn, of their patients deaths, when the deaths occur in an institution in which the General Practitioner has no direct role in their care. DESIGN: Using a semi-structured telephone questionnaire the relevant General Practitioners were asked of the method, if any, by which they had learned of their patients deaths, and their views on this. SETTING: Sligo, Ireland. RESULTS: In 6 (16%) of the 37 cases, the GP was informed of the death within one working day by hospital staff. In 22 (59%) of the cases, the GP had learned of the death through other means. In 9 (26%) of the cases the GP had not learned of the death. In 28 (75%) of the cases, the GPs were dissatisfied with either the fact that they did not know of the death, or even if they did know, the method by which they learned of the patients death. CONCLUSION: General Practitioners, for a variety of reasons, wish to learn of their patient's deaths within a short length of time of such deaths occurring. When deaths occur in an institution in which the GP has no direct role in the care of their patients, the information is not forwarded to the GP within a reasonable length of time in the vast majority of cases. Such institutions need to realise the importance of this simple act, and to make it routine to forward the information.

Attitude of Health Personnel↗

Learning and generalization of auditory temporal-interval discrimination in humans.

The sensory encoding of the duration, interval, and order of different stimulus features provides vital information to the nervous system. The present study focuses on the influence of practice on auditory temporal-interval discrimination. The goals of the experiment were to determine (1) whether practice improved the ability to discriminate a standard interval of 100 msec bounded by brief 1 kHz tones from longer intervals, and, if so, (2) whether this improvement generalized to different tonal frequencies or temporal intervals. Learning was examined in 14 human subjects using an adaptive, two-alternative, forced-choice procedure. One hour of training per day for 10 d led to marked improvements in the ability to discriminate between the standard and longer intervals. The generalization of learning was evaluated by independently varying the spectral (tonal frequency) and temporal (interval) components of the stimuli in four conditions tested both before and after the training phase. Remarkably, there was complete generalization to the trained interval of 100 msec bounded by tones at the untrained frequency of 4 kHz, but no generalization to the untrained intervals of 50, 200, or 500 msec bounded by tones at the trained frequency of 1 kHz. Thus, these data show that (1) temporal-interval discrimination using a 100-msec standard undergoes perceptual learning, and (2) the neural mechanisms underlying this learning are temporally, but not spectrally, specific. These results are compared with those from previous investigations of learning in visual spatial tasks, and are discussed in relation to biologically plausible models of temporal processing.

Acoustic Stimulation↗

Objectives and students' learning in general practice.

Student views of objectives and learning, during 4 weeks spent in general practice in the fifth year, are compared to those of the GPs to whom they were attached. Relationships between these views are discussed, together with their implications, for the wider contributions made by general practitioners to the undergraduate curriculum.

Education, Medical, Undergraduate↗

Reduced feedback frequency enhances generalized motor program learning but not parameterization learning.

The purpose of the study was to examine the effects of a reduced feedback frequency on the learning of generalized motor programs and movement parameterization. Subjects practiced three movement patterns with the same relative timing and the same relative amplitude, but with varied movement time (Experiment 1) or varied movement amplitude (Experiment 2). KR was given either on 100% or 63% of the trials, with learning being assessed by retention and transfer tests. In both experiments, reduced KR frequency enhanced GMP learning but generally degraded parameter learning. These data provide converging evidence for the dissociation of the program and parameterization processes postulated in GMP theory.

Adult↗

Does dietary learning occur outside awareness?

Several forms of dietary learning have been identified in humans. These include flavor-flavor learning, flavor-postingestive learning (including flavor-caffeine learning), and learned satiety. Generally, learning is thought to occur in the absence of contingency (CS-US) or demand awareness. However, a review of the literature suggests that this conclusion may be premature because measures of awareness lack the rigor that is found in studies of other kinds of human learning. If associations do configure outside awareness then this should be regarded as a rare instance of automatic learning. Conversely, if awareness is important, then successful learning may be governed by an individual's beliefs and predilection to attend to stimulus relationships. For researchers of dietary learning this could be critical because it might explain why learning paradigms have a reputation for being unreliable. Since most food preferences are learned, asking questions about awareness can also tell us something fundamental about everyday dietary control.

Association Learning↗

Error consistency and the evaluation of treatment outcomes.

The consistency/variability of error substitution patterns may hold important implications for subgrouping children with speech disorders, as well as for relationships between learning and generalization patterns. There is a need to quantify and examine the range of consistency/variability within the speech disordered population as it relates to system-wide change. This investigation compared two groups of preschool children (N = 10 each) differing in the consistency/variability of errors on a variety of pre-treatment and treatment outcome measures. The Error Consistency Index (ECI), a measure of error variability across the entire phonological system, was used to identify groups at the extreme ends of the ECI distribution from a larger participant pool. Each participant was treated on three target singletons from among obstruents /s, z, f, integral, tintegral, k, g/ and liquids /l, r/ and change on these targets, as well as their generalization to untrained positions was assessed. Although there were significant differences between the variable and consistent groups on all pre-treatment measures, there were no significant group differences in target and generalization learning or in per cent consonants correct (PCC) change. These findings provide evidence to suggest that relationships observed between error variability for individual phonemes and learning of those targets may differ from those observed when consistency/variability is quantified for the entire system and change across a number of phonemes, and the system as a whole, is examined.

Child Language↗

Right hemisphere, white-matter learning disabilities associated with depression in an adolescent and young adult psychiatric population.

Four hundred and eighty-four adolescents and young adults at an inpatient psychiatric facility were diagnosed as nonverbal learning disabled, verbal learning disabled, general learning disabled, or normal psychiatric controls. The nonverbal learning disabled group had the highest incidence of depression and was clearly different from the reading disabled group (66.3% vs. 33.3%). Nondisabled subjects were significantly more likely than the other subjects to be diagnosed with adjustment problems. Depressed subjects were significantly younger and more likely to be female. This study supports the contention that right-hemisphere, white-matter, arithmetic-disabled adolescents and young adults in a psychiatric population are at greater risk for depression than are psychiatric patients not showing this pattern.

Achievement↗

A questionnaire examining learning in general practice.

Vocational training is a key element of professional development in general practice. Learner-centred approaches to teaching bring a need for greater understanding of the individual learning styles and preferences of trainees. This paper reports the findings of a pilot study undertaken to determine factors that may influence learning among general practice trainees. A questionnaire survey of 261 trainees in six regions in the UK was carried out to explore attitudes to a series of themes identified in semi-structured interviews with trainees at the end of their training. Six distinct subscales were identified using principal components analysis. These are named 'Learning from Patients', 'Openness to Criticism', 'Negative Attitudes', 'Desire for Clear Guidelines', 'Peer Support', and 'Academic Approach'. Males scored significantly higher on 'Academic Approach' (P < 0.05). Each of the subscales reflects themes that permeate the atmosphere of general practice training. Further work is required to establish relationships between the subscales and the outcomes of learning and to explore the implications for continuing professional development. The questionnaire is an instrument that may prove useful in the future investigation of learning in general practice.

Family Practice↗

Effects of speech and speech and sign instruction on oral language learning and generalization of action + object combinations by Down's syndrome children.

This study was designed to compare the effects of speech and speech-plus-sign stimulation during comprehension treatment on the oral language learning and generalization of action + object relational meanings. Ten home-reared Down's syndrome children in Early Stage 1 received concurrent comprehension treatment in Speech and Speech-Sign conditions using a miniature linguistic system. Upon attainment of criterion level performance in both conditions, generalization tasks were administered to measure the effects of the comprehension treatment on the comprehension and the production of treated and untreated action + object combinations. The results obtained from this study indicated that the two treatment conditions did not differ significantly for either learning or generalization. The data did, however, indicate that individual patterns of acquisition were evident among the children. Caution is advised concerning the automatic adoption or rejection of manual sign as part of oral language intervention programs.

Child↗

Portfolio learning in general practice vocational training--does it work?

Reflective learning has been widely addressed as an important learning mechanism in the educational literature. The creation of portfolios has been seen as a mechanism to promote this, though there has been little exploration of the place of a portfolio in general practice training. This study examined the introduction of a model of a portfolio learning strategy into one training region. The model had been developed by previous pilot work. The study explored the model in terms of its usefulness in general practice training and its relationship to reflective learning. An educational facilitator was used to support this introduction. Workshops and written material were developed to disseminate and refine ideas generated in the pilot study. This was followed by visits to trainer/general practice registrar (GPR) pairs over a 2-year period. These visits included semistructured interviews, which were tape-recorded and analysed using qualitative methods. Additional written resources, video and audio material as well as new workshops were designed with the researched participants in order to promote the development of the concepts of portfolio learning. Sixty interviews were carried out over a 2-year period with 44 pairs of trainers and GPRs. This included a total of 27 trainers and 44 registrars. Eighteen pairs were interviewed twice. Two focus groups were used at the end of the project. Portfolios have a place to play in general practice vocational training. They act as a bridge between hospital and general practice. They can be used to develop a learner-centred curriculum, explore difficult emotive concerns and facilitate feedback. They do not suit all learning styles. Their use is determined by a cost-benefit analysis described in this study.

Education, Medical, Graduate↗

Stimulus generalization, discrimination learning, and peak shift in horses.

Using horses, we investigated three aspects of the stimulus control of lever-pressing behavior: stimulus generalization, discrimination learning, and peak shift. Nine solid black circles, ranging in size from 0.5 in. to 4.5 in. (1.3 cm to 11.4 cm) served as stimuli. Each horse was shaped, using successive approximations, to press a rat lever with its lip in the presence of a positive stimulus, the 2.5-in. (6.4-cm) circle. Shaping proceeded quickly and was comparable to that of other laboratory organisms. After responding was maintained on a variable-interval 30-s schedule, stimulus generalization gradients were collected from 2 horses prior to discrimination training. During discrimination training, grain followed lever presses in the presence of a positive stimulus (a 2.5-in circle) and never followed lever presses in the presence of a negative stimulus (a 1.5-in. [3.8-cm] circle). Three horses met a criterion of zero responses to the negative stimulus in fewer than 15 sessions. Horses given stimulus generalization testing prior to discrimination training produced symmetrical gradients; horses given discrimination training prior to generalization testing produced asymmetrical gradients. The peak of these gradients shifted away from the negative stimulus. These results are consistent with discrimination, stimulus generalization, and peak-shift phenomena observed in other organisms.

Animals↗

Contextual quick-learning and generalization by humans and machines.

In a previous study (1994 Network: Comput. Neural Syst. 5 203-27) we compared human quick-learning and generalization (quick modelling) with that of neural nets (feedforward architectures), symbolic algorithms (decision tree procedures), and pattern classifiers (truth-set descriptors). Those studies raised the question of the role of context in the nature and rapidity of human learning. Here we address that issue in the setting of the same basic experiment (Quinlan classification problem) used for the previous studies. A major implication of our findings is that humans overwhelmingly seek, create, or imagine context in order to provide meaning when presented with abstract or apparently incomplete or contradictory or otherwise untenable situations.

Adolescent↗