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PubMed2025

Accurate prediction of toxicity peptide and its function using multi-view tensor learning and latent semantic learning framework.

MOTIVATION: Therapeutic peptide is an important ingredient in the treatment of various diseases and drug discovery. The toxicity of peptides is one of the major challenges in peptide drug therapy. With the abundance of therapeutic peptides generated in the post-genomics era, it is a challenge to promptly identify toxicity peptides using computational methods. Although several efforts have been made, few algorithms are designed to identify whether a query peptide exhibits toxicity. Considering the varied levels of biological activities, the toxicity peptides should be further classified into multi-functional peptides. RESULTS: This study introduces a two-level predictor, ToxPre-2L, developed using the multi-view tensor learning and latent semantic learning framework. The proposed method utilized multi-label learning with feature induced labels to avoid the redundancy of information from each view. Then the multi-view tensor learning was employed to establish the latent semantic information among different views, while low-rank constraint learning was leveraged to exploit the correlation information among multi-labels. Finally, we constructed an updated toxicity peptide benchmark dataset to assess the effectiveness of the proposed method. Experimental results demonstrated that ToxPre-2L achieves a better performance than alternative computational methods in the prediction of toxicity peptides and their multi-functional types. AVAILABILITY AND IMPLEMENTATION: The source code and data of ToxPre-2L can be accessed at http://bliulab.net/ToxPre-2L.

Peptides↗

PubMed1990

Learning to solve a problem: a microanalysis of the solution strategies of children with learning disabilities.

Ten subjects with learning disabilities and 10 normally achieving subjects, aged 10-5 to 12-5 years, were videotaped while attempting to solve the Tower of Hanoi problem (see Karat, 1982; Piaget, 1976; Simon, 1975). A microanalysis of their problem-solving activities provided a descriptive taxonomy used to analyze what, in fact, individual subjects did when constructing a solution strategy, and to categorize and compare changes in strategy. The results indicated that as a group the normally achieving subjects reached more sophisticated levels of strategy use (p less than .05). However, if the focus of the comparison is on an analysis of how learning proceeded in individuals, then the subjects with learning disabilities appear to be similar to the normally achieving subjects. There was no evidence in these subjects of the popular conception that individuals with learning disabilities are inactive, passive, or maladaptive in their attempts to learn to solve a problem.

Attention↗

PubMedDate not supplied

Assessment of learning abilities using complex experimental learning tasks.

Efforts are underway to develop a computerized methodology for the reliable, valid measurement of learning abilities. Central to these research efforts are the development of Complex Experimental Learning Tasks (CELTs) that provide real-time samples of learning. Objectives of current studies are the determination of relationships between performance on CELTs and performance on traditional cognitive abilities tests and the exploration of predictive value of measures of learning ability for academic performance. After construct and predictive validity are established, this methodology may be applicable to a wide range of assessment situations, including testing for the effects of environmental toxicants on learning abilities.

Aptitude Tests↗

PubMed2026

ORBIT: Oncogenic Representation Learning via Bi-Prototype Contrastive Learning in Hyperbolic Space for cancer driver gene identification.

Accurate identification of cancer driver genes is crucial for precision oncology but remains challenging due to the complexity of integrating heterogeneous data and modeling dynamic biological systems. To address these limitations, we propose ORBIT (Oncogenic Representation Learning via Bi-Prototype Contrastive Learning in Hyperbolic Space). Our framework synergistically fuses multi-omics profiles with functional network data using a context-adaptive graph reweighting mechanism to capture cancer-specific dynamics. The model employs a bi-prototype contrastive learning strategy within hyperbolic space, which aligns gene representations around distinct driver and non-driver semantic anchors while preserving the intrinsic hierarchy of biological networks. Comprehensive evaluations demonstrate that ORBIT achieves highly competitive stability in pan-cancer analysis while consistently outperforming state-of-the-art methods in cancer-specific predictions. Furthermore, functional enrichment analysis confirms that the model effectively segregates core cancer pathways, and drug sensitivity profiling validates the clinical relevance of the identified drivers. By integrating hyperbolic geometry with context-adaptive learning, ORBIT offers a robust and interpretable paradigm for precision medicine. The source codes and datasets are publicly accessible at https://github.com/spcho-dev/ORBIT.

Humans↗

PubMed1990

A taste aversion model of drug discrimination learning: training drug and condition influence rate of learning, sensitivity and drug specificity.

A model of drug discrimination based on a lithium chloride (LiCl) flavour aversion was described and examined. Mildly thirsty rats were presented daily with 4 ml of a distinctly flavoured solution which was followed on 50% of the days by an IP injection of LiCl. Prior to the flavour presentation, the rats were injection SC with saline or a training drug (0.04 mg/kg fentanyl or 20 mg/kg pentobarbital) to signal whether LiCl would follow. Almost all rats eventually exhibited stable behaviour that involved drinking most or all of the fluid when it was not to be followed by LiCl and little or no drinking when it was. Such discrimination occurred regardless of whether drug predicted LiCl (learned-discomfort) or predicted no LiCl (learned-safety). However, with fentanyl there were clear differences between rats trained with drug under learned-safety and under learned-discomfort conditions for 1) the rate of acquisition of stable performance as a function of LiCl dose, 2) generalization of the training dose to a test dose that was lower, and 3) elicitation of fentanyl responses by pentobarbital. These findings, together with indications that such effects did not always occur with pentobarbital as the training drug, were discussed from theoretical and practical perspectives.

Animals↗

PubMed1987

Paired associate learning in reading-disabled children: evidence for a rule-learning deficiency.

Two experiments examined whether normal and disabled readers differed in the utilization of rules in a paired associate learning task. Experiment 1 required children to learn symbol-word associates. Children were assigned to one of three conditions: nonrule, consistent rule, or inconsistent rule. When present, the rule was based on semantic opposites. Subjects benefited from having the rule, but disabled readers showed less improvement across four test blocks than both chronological age (CA) controls and reading age (RA) controls, particularly in the inconsistent condition. Experiment 2 required subjects to learn symbol-symbol associations in one of three conditions: nonrule, consistent rule, or inconsistent rule. When present, the rule specified the locations of a subsidiary figure in each symbol according to the pattern top-right, bottom-left. Disabled and normal readers did not differ in the nonrule condition where reliance on visual memory would be an effective strategy. Normal readers were superior to disabled readers in both rule conditions. In addition, disabled readers in the inconsistent rule condition were less able than normal readers to apply the rule in a generalization task where memory demands were reduced. Results supported the hypothesis that disabled readers have greater difficulty than normal readers inducing and/or using rules, particularly when they are inconsistent. It is suggested that difficulties in acquiring or using complex and inconsistent rules may be one important source of problems learning spelling-sound correspondence rules, which in English are complex and inconsistent.

Association Learning↗

PubMed2026

Implicit and explicit statistical learning in reading: Evidence from a randomized controlled-learning study and computational modeling.

A key challenge in reading acquisition is understanding how learners extract the complex probabilistic mappings between print, meaning, and sound. Statistical learning (SL) theory offers a mechanistic account of how such mappings are acquired, whether implicitly through exposure or explicitly through instruction. We conducted a randomized controlled-learning study in Chinese, a writing system characterized by multiple sub-lexical regularities linking orthography, semantics, and phonology. Ninety-five 2nd-3rd graders with or at risk for dyslexia were randomly assigned to one of three groups: an implicit-SL training group exposed to repeated lexical and sublexical orthography-semantics-phonology associations, an explicit-SL training group receiving the same input plus explicit instruction on the sublexical print-sound mapping, and a no-SL control group. Both SL groups outperformed controls on the characters they were trained on, as well as on untrained characters that required generalization. However, only the explicit group demonstrated abstraction of print-sound mapping to novel items. Neural network simulations further revealed distinct mechanisms supporting implicit and explicit SL, consistent with a dual-system account of reading acquisition. Together, these findings (1) clarify how implicit and explicit learning distinctly support the discovery of statistical structure in written language and (2) underscore the implicit-explicit dual learning mechanism underlying reading acquisition.

Humans↗

PubMed1992

Learning behaviour in chronic vitamin E-deficient and -supplemented rats: radial arm maze learning and passive avoidance response.

The effects of long-term vitamin E deficiency and supplementation on learning behaviour were investigated. Rats were fed vitamin E-deficient [VE(-)], -supplemented [VE(+)], or control standard food beginning after the age of 4 weeks. They were trained in an eight-arm radial maze learning task at the age of 17 months, and in a step-through passive avoidance response (PAR) task at the age of 25 months. In the radial maze task, both VE(-) and VE(+) animals required as many trials to reach the learning criterion as control animals. Scopolamine injection (0.25-0.5 mg/kg) after acquisition of the task decreased the number of correct choices dose-dependently; however, the degree of the drug effect on VE(-) and VE(+) rats did not differ from that on control rats. On the other hand, VE(-) animals showed significantly lower rate of avoidance response and VE(+) animals tended to show higher rate of avoidance response in the PAR task than did control animals. These results suggest that long-term vitamin E deficiency or supplementation does not influence general ability to acquire and maintain memory tasks in rats, but that it may affect learning behaviour, depending on the kind of task in which animals were trained.

Age Factors↗

PubMed1988

Learning in rats with caudate-putamen lesions: unimpaired classical conditioning and beneficial effects of redundant stimulus cues on instrumental and spatial learning deficits.

The effects of caudate-putamen lesions in the rat on conditioning were investigated in three experiments. In Experiment 1, rats with lesions were impaired on a spatial task that required learning to make the correct position response, but no deficit was obtained when the alternatives were differentiated by salient visual cues. Performance remained good even when the visual cues were removed. A classical conditioned suppression paradigm was used in Experiment 2, and caudate-putamen lesions were found not to impair acquisition of suppression or overshadowing. In Experiment 3 we revealed poor instrumental learning in subjects with lesions as retarded acquisition of lever-press responding and depressed variable interval response rates. When a light stimulus was present together with reinforced responses, response rates were depressed in the control group (which suggested an overshadowing phenomenon) but were potentiated in the group with lesions. The results showed that caudate-putamen lesions did not produce a general deficit in association formation. There was disruption of learning about responses but not stimuli and, moreover, it was found that redundant stimulus cues aided response learning. It appears that for normal subjects, the salience or associability of the response cues may largely determine the influence of stimuli presented during instrumental conditioning.

Animals↗

PubMed1979

Aging in the rhesus monkey: effects on visual discrimination learning and reversal learning.

The behavior of aged rhesus monkeys (18 years and older) was compared to that of young monkeys (3 to 6 years old) to evaluate their relative abilities to learn a series of visual discrimination and discrimination reversal problems. Using a subject-paced, automated experimental procedure designed to optimize stimulus control and facilitate execution of choice responses, no consistent age-related differences were observed in the ability to learn new color and pattern discrimination problems of varying difficulty. However, a severe and consistent deficity on reversal learning did occur. A detailed analysis of this deficit revealed that not only did the aged monkeys take longer to extinguish the old habit and return to chance performance, but they continued to display a deficit in establishing accurate performance at above-chance levels as well. Since no reliable age differences were observed on the original discrimination learning problems, these data suggest that aging impairs mechanisms involved with response rigidity and/or susceptibility to intertrial proactive interference, more severely than those involved with the simple formation of new associations.

Aging↗

PubMed1989

Learning ability in young rats with single and double lesions to the "general learning system".

Previous lesion studies suggest that the dorsal caudatoputamen (DCP), globus pallidus, ventrolateral thalamus (VLT), substantia nigra, ventral tegmental area, superior colliculus (SC), median raphe, and pontine reticular formation are components of the general learning system (GLS) of the rat brain. The current study attempted to determine whether bilateral lesions to two components of the GLS (DCP/VLT, DCP/SC or VLT/SC) would produce greater deterioration of learning ability than bilateral lesions to only one component (DCP, VLT or SC). In all combinations examined, a second lesion added to the first led to a significantly greater learning decrement on a series of spatial reversal problems than that associated with the first lesion alone. These results are compatible with the view that the foregoing structures are elements of the same functional system concerned either directly or indirectly with general learning ability.

Animals↗

PubMed1979

Learned helplessness and learned effectiveness: effects of explicit response cues on individuals differing in personal control expectancies.

Female undergraduates (n = 62) who scored as extreme internals or externals on the Mirels Personal Fate Control Scale participated in a partial replication of Hiroto's learned helplessness experiment. Lights were added to the treatment apparatus, which made explicit to subjects the contingency or noncontingency between their responses and the termination of an aversive tone. As predicted, the performance of internals was significantly impaired by uncontrollability (learned helplessness), while that of externals was facilitated by controllability (learned effectiveness). Externals performed as well as internals in the "escapable" condition, but their performance was inferior to that of internals in the control condition. Following "inescapable" treatment, internals performed worse than externals. These results are supportive of Lefcourt's theory of cue explication. Implications for locus of control and learned helplessness research are discussed.

Acoustic Stimulation↗

PubMed1979

The inability to transfer classroom learning to clinical nursing practice: a learning problem and its remedial plan.

The inability to transfer classroom knowledge to clinical nursing practice is a common learning problem encountered by many nursing students. Manifestations of this problem may involve both the academic performance and personal development of the students: inability to solve problems in nursing situations; inflexibility and rigidity in the exercise of nursing care; fragmentation of nursing care; and apathy towards clinical practice. Because of the seriousness of this learning problem, a plan must be formulated to rectify it. This plan is developed with major emphasis on the teaching process, the student and the curriculum. One of the important roles of a teacher is to help students understand many widely useful relationships, principles or generalizations. In order to enhance transfer, nursing students must be given ample opportunities to apply the learned principles in a variety of nursing situations. Learning is a self-active process; an ideal transfer demands the students' conscious realization that transfer is possible. Students need to be committed to the belief that particular facts in the classroom study are pertinent in other situations. To promote transfer, the curriculum must be designed in such a way so that it has transfer value in terms of the students' goals and purposes. Furthermore, proper sequence of curricular activities is crucial if transfer of classroom knowledge to clinical practice is to occur.

Adaptation, Psychological↗

PubMed1988

Observation as a method of learning: a useful learning experience or a waste of time?

In medical schools, most clinical teaching takes place in small groups in which the teacher and/or one of the students carry out the interview, examination or procedure, while one or more of the other members of the group looks on. Students, then, are as often watchers as doers. What do students learn from observing someone else doing something, and what can be done to enhance the effectiveness of this learning process? The authors attempted to answer these questions. They conducted an experimental study designed to evaluate student experience as observers. The data garnered from this study indicated that students regarded learning by observation as a useful, even valuable, experience. The data also suggested that the effectiveness of this learning experience was derived from a shared sense of immediate, emotionally charged, highly interactive participation in the proceedings, and that the teacher's catalytic function was essential to this process.

Adolescent Psychiatry↗

PubMed1989

On learning ... more or less: a knowledge x process x context view of learning disabilities.

The authors review the last decade of their research on learning disabilities and conclude that knowledge x process x context is the most useful way to think about children's cognitive difficulties. According to this framework, learning disabilities is seen as a result of the interplay between a poorly elaborated knowledge base (especially in language-related domains), the biologically determined efficiencies of various microlevel processes such as encoding, and the physical and social meaning attached to performance (i.e, the context). It is suggested that this framework helps explain instances of asymmetry wherein children with learning disabilities deploy a cognitive process more or less efficiently, depending on the material and task demands. It also raises several interesting questions about the presumed "specificity" of the impairment underlying learning disablement and the possibility that these children may not differ qualitatively from nonimpaired peers, only quantitatively.

Adolescent↗

PubMed1992

What do medical students seek to learn from general practice? A study of personal learning objectives.

With the aim of stimulating learning which is more self directed, fourth year medical students in Liverpool are encouraged to set personal learning objectives for the general practice attachment. On average, a student defines seven objectives for the three week attachment. A classification of objectives derived from the 1989 cohort of students is presented and the objectives could be seen as focusing on the practice population and its health problems, the role of the general practitioner, the work of general practice, the management of general practice, general practice as a career, and general learning. The validity and reliability of the classification are considered. Along with the advantages of this approach in motivating students to learn, the findings are considered in relation to impending changes in undergraduate medical education and the future role of general practice teaching by departments and by practice based colleagues.

Curriculum↗

PubMed1990

[Change in cardiovascular activation in learning and performance situations in children with learning disorders].

A method is demonstrated for observing and statistically testing changes in cardiovascular activity in single cases between two types of situations, in this case a playing situation and a learning situation. Using this method it could be shown an abasement of cardiovascular activity during a learning situation together with their mother or father--compared to a playing situation--for 20 hyperactive children with learning problems of an average age of 9.7 years. Together with this abasement in cardiovascular activity there was observed a deterioration in the parent-child-relation. In the singles cases however it could be observed an abasement or an increase in cardiovascular activity. When the--often punishing--parent was replaced by a person who built up a positive relation to the child, there could be observed either an increase or an abasement or no change in cardiovascular activity, the effect being replaiable. The results point up to a critical examination of actual therapeutic concepts for children with learning problems.

Achievement↗

PubMedDate not supplied

Neurochemical specificity of learning: dopamine and motor learning.

In previous reports of studies of patients with alcoholic Korsakoff's psychosis, data were presented showing significant correlations between neuropsychometric measures of amnesia and the CSF levels of the major brain metabolite of norepinephrine (NE), which was consistently reduced among a large group of experimental subjects. Dopamine (DA) metabolite concentrations in the CSF of this same patient population were also significantly lowered but to a lesser degree and less consistently than the NE metabolite. CSF levels of the DA metabolite did not correlate with any measures of amnesia but did significantly correlate with performance on the Digit-Symbol Substitution Test (DSST) of the Wechsler Adult Intelligence Scale (WAIS), which involves psychomotor skill learning. DSST performance did not correlate with CSF levels of the NE metabolite. These findings led to the hypothesis that the acquisition of motor learning skills is related to brain DA activity. In this study, we tested the hypothesis by correlating the ability of a group of Korsakoff patients to learn two different motor tasks (rotary pursuit and mirror tracing) with the concentrations of CSF metabolites of NE, DA, and serotonin. For both tasks, improvement in performance over three daily testing sessions significantly correlated only with the DA metabolite levels. The data are consistent with the hypothesis of a specific role for DA in motor learning.

Alcohol Amnestic Disorder↗