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PubMed1978

Laterality preference patterns of learning disabled children.

This study concerned the prediction of group membership of 40 learning disabled and 40 normal children on the basis of preference for laterality of the children and of their parents. A stepwise discriminant analysis showed maternal and paternal lateral preferences could correctly identify approximately 85% of the cases. Orthogonal contrasts showed that, although children themselves did not differ in the degree of laterality, parents of learning disabled children were significantly more bilateral in their preference patterns than normals.

Child↗

PubMed2004

Orthographic learning at a glance: on the time course and developmental onset of self-teaching.

Experiment 1 examined the time course of orthographic learning among Grade 3 children. A single encounter with a novel orthographic string was sufficient to produce reliable recall of orthographic detail. Moreover, newly acquired orthographic information was retained 1 month later. These data support the logistic learning functions featured in contemporary connectionist models of reading rather than a "threshold" model of orthographic learning. Experiments 2 and 3 examined self-teaching among novice readers. In contrast to the findings from less regular orthographies such as English and Dutch, beginning readers of a highly regular orthography (Hebrew) appear to be relatively insensitive to word-specific orthographic detail, reading in a nonlexical "surface" fashion. These results suggest fundamental differences between shallow and deep orthographies in the development of orthographic sensitivity.

Child↗

PubMed2006

No evidence for learned mating discrimination in male Drosophila pseudoobscura.

BACKGROUND: Since females often pay a higher cost for heterospecific matings, mate discrimination and species recognition are driven primarily by female choice. In contrast, frequent indiscriminate matings are hypothesized to maximize male fitness. However, recent studies show that previously indiscriminate males (e.g., Drosophila melanogaster and Poecilia reticulata) can learn to avoid heterospecific courtship. This ability of males to discriminate against heterospecific courtship may be advantageous in populations where two species co-occur if courtship or mating is costly. RESULTS: Here, we tested whether Drosophila pseudoobscura males learn to discriminate against heterospecific females after being exposed to and rejected by D. persimilis females. In most of our assays, we failed to observe differences in D. pseudoobscura courtship intensity of heterospecific females by males that had previously courted heterospecific females vs. males that had been maintained in isolation. CONCLUSION: We conclude that learning to avoid heterospecific courtship may not be universal, even within the genus Drosophila, and may possibly be dependent on the natural history of the species.

Animals↗

PubMed2006

Cognitive and physical activity differently modulate disease progression in the amyloid precursor protein (APP)-23 model of Alzheimer's disease.

BACKGROUND: In aging mice, activity maintains hippocampal plasticity and adult hippocampal neurogenesis at a level corresponding to a younger age. Here we studied whether physical exercise and environmental enrichment would also affect brain plasticity in a mouse model of Alzheimer's disease (AD). METHODS: Amyloid precursor protein (APP)-23 mice were housed under standard or enriched conditions or in cages equipped with a running wheel. We assessed beta-amyloid plaque load, adult hippocampal neurogenesis, spatial learning, and mRNA levels of trophic factors in the brain. RESULTS: Despite stable beta-amyloid plaque load, enriched-living mice showed improved water maze performance, an up-regulation of hippocampal neurotrophin (NT-3) and brain-derived neurotrophic factor (BDNF) and increased hippocampal neurogenesis. In contrast, despite increased bodily fitness, wheel-running APP23 mice showed no change in spatial learning and no change in adult hippocampal neurogenesis but a down-regulation of hippocampal and cortical growth factors. CONCLUSIONS: We conclude that structural and molecular prerequisites for activity-dependent plasticity are preserved in mutant mice with an AD-like pathology. Our study might help explain benefits of activity for the aging brain but also demonstrates differences between physical and more cognitive activity. It also suggests a possible cellular correlate for the dissociation between structural and functional pathology often found in AD.

Alzheimer Disease↗

PubMed1991

Rapid odor conditioning in newborn rabbits: amnesic effect of hypothermia.

Rabbit pups are completely dependent on a maternal pheromone for the release of suckling behavior. However, if the mother is perfumed prior to nursing, pups will learn to respond to the novel odor with the characteristic nipple-search behavior in just one 3-4 min nursing episode. In a first investigation of the processes underlying this recently developed learning paradigm, time-dependent effects of hypothermia on retention of the task could be demonstrated. Thus pups whose whole body was cooled to a mouth temperature of 7 degrees C immediately after conditioning (n = 10) and tested 24 h later for 3 min on a perfumed fur did not differ significantly in their search response from naive, untreated controls (n = 10). In contrast, pups cooled 4 h after conditioning (n = 10) demonstrated clear retention of the learned response and searched as vigorously as conditioned but uncooled animals (n = 10). As pups of all groups demonstrated normal nipple-search behavior when tested on a lactating doe, the deficits associated with immediate cooling appear to have been specific to the learning task and time of treatment.

Animals↗

PubMed2000

Constrained scaling: the effect of learned psychophysical scales on idiosyncratic response bias.

We report seven experiments in which subjects were trained to respond with numbers to the loudness of 1000-Hz pure tones according to power functions with exponents of 0.60, 0.30, and 0.90. Subjects were then presented with stimuli from other continua (65-Hz pure tones or 565-nm lights varying in amplitude) and were asked to judge the subjective magnitude of these stimuli on the same numerical scale. Stimuli from the training continuum were presented, with feedback, on every other trial in order to maintain the trained scale. Except for the 0.90 scale, subjects readily learned the predetermined scales and were able to use them to judge the non-training stimuli with group results consistent with those usually reported. Also, in contrast to the usual magnitude estimation results, these results produced extremely low levels of intersubject variability. We argue that such learned scales can be used as "rulers" for measuring perceived magnitudes, according to a common unit.

Auditory Perception↗

PubMedDate not supplied

[Motor cortex functions in the reorganization of postural coordinations].

A well-known function of the motor cortex (MCx) is control of the limb distal musculature, in particular, isolated finger movements during precise and fine hand movements. However, MCx has another function connected with the motor learning process, namely, a suppression of synergies and coordinations interfering with a movement being elaborated. This was shown for various limb movements. However, majority of movements is accompanied by postural adjustment as well. Two experimental models of rearrangement of an innate pattern of the postural adjustment were developed, and MCx was shown during such kind of learning to suppress the activity of structures providing the innate postural patterns. In contrast to the control of limb movements, the MCx influences were found to be bilateral for the postural pattern reorganization. It was revealed recently, however, that a possibility of recovery for the sequential MCx lesions depends on the sequence of the lesions, so, perhaps the role of MCx of different hemispheres in the compensation is different.

Animals↗

PubMed2005

Adult rat forelimb dysfunction after dorsal cervical spinal cord injury.

Repairing upper extremity function would significantly enhance the quality of life for persons with cervical spinal cord injury (SCI). Repair strategy development requires investigations of the deficits and the spontaneous recovery that occurs when cervical spinal cord axonal pathways are damaged. The present study revealed that both anatomically and electrophysiologically complete myelotomies of the C4 spinal cord dorsal columns significantly increased the adult rat's averaged times to first attend to adhesive stickers placed on the palms of their forepaws at 1 week. Complete bilateral myelotomies of the dorsal funiculi and dorsal hemisection, but not bilateral dorsolateral funiculi injuries, also similarly increased these times at 1 week. These data extend a previous finding by showing that a forepaw tactile sensory deficit that occurred in the adult rat after bilateral C4 spinal cord dorsal funiculi injury is due to damage of the dorsal columns. Averaged times to first attend to the stickers also decreased to those of sham-operated rats at 3 and 4 weeks post-dorsal hemisection with weekly testing. In contrast, a separate group of rats with dorsal hemisections had significantly increased times when tested only at 4 weeks. These data indicate that frequent assessment of this particular behavior in rats with dorsal hemisections extinguishes it and/or engenders a learned response in the absence of sensory axons in the dorsal columns and dorsolateral funiculi. This finding contrasted with weekly testing of grid walking where increased forelimb footfall numbers persisted for 4 weeks post-dorsal hemisection.

Afferent Pathways↗

PubMedDate not supplied

Sedative effects of antihistamines: safety, performance, learning, and quality of life.

Antihistamines are frequently part of the treatment regimen for seasonal and perennial allergic rhinitis occurring alone or in conjunction with associated airway disorders, such as asthma, sinusitis, and otitis media with effusion. These agents are also frequently prescribed for the treatment of urticaria to eliminate the need for long-term corticosteroids. This paper reviews the side-effect profile of the sedating and nonsedating agents (a classification given these drugs by the US Food and Drug Administration) in terms of patient satisfaction and quality-of-life parameters. Because the sedating antihistamines cross the blood-brain barrier more quickly and easily than the nonsedating antihistamines, they produce more central nervous system (CNS) effects, further exacerbating the decreases in decision-making, verbal learning, and psychomotor skills already experienced by the patient with allergic rhinitis. In contrast the now-preferred nonsedating agents do not readily cross the blood-brain barrier, do not produce CNS side effects, and, therefore, do not cause sedation or performance impairment. The nonsedating agents provide a safer alternative for patients with allergic rhinitis. Their use can increase patient satisfaction with the health care received.

Cognition↗

PubMed2006

Prenatal stress in the rat alters 5-HT1A receptor binding in the ventral hippocampus.

Exposure of a pregnant woman to physical and/or psychological stress might affect her offspring by promoting the development of various learning, behavioral and/or mood disorders in later life. The 5-HT1A and 5-HT2A receptors are prominently implicated in the modulation of anxiety and mood-related behaviors. Using a semi-quantitative radiolabel immunocytochemical analysis (immunobinding), we studied the effect of prenatal stress on binding of these two receptor subtypes in the hippocampus of 4-week-old male and female Fischer 344 rats. Levels of 5-HT1A immunobinding in the ventral hippocampus, which is primarily implicated in emotional processing, were significantly decreased in male offspring after prenatal stress. A trend towards a decrease was observed in the ventral hippocampus of females. In contrast, 5-HT1A immunobinding within the dorsal hippocampus, which is mainly related to learning and memory, was not affected by prenatal stress in offspring of either gender. Likewise, no significant differences between control and prenatally stressed rats were observed for levels of 5-HT2A immunobinding in either part of the hippocampus or gender. The observed reduction in hippocampal 5-HT1A receptor binding in male offspring after prenatal stress may have important consequences for adult anxiety- and depressive-like behavior.

Animals↗

PubMed1998

Role of the striatum, cerebellum and frontal lobes in the automatization of a repeated visuomotor sequence of movements.

Recently, Doyon et al. [20] demonstrated that lesions to both the striatum and to the cerebellum in humans produce a similar deficit in the learning of a repeated visuomotor sequence, which occurs late in the acquisition process. We now report the results of two experiments that were designed to examine whether this impairment was due to a lack of automatization of the repeating sequence of finger movements by using a dual-task paradigm and by testing for long-term retention of this skill. In Experiment 1, the performance of groups of patients with Parkinson's disease, or with damage to the cerebellum or to the frontal lobes, was compared to that of matched control subjects on the Repeated Sequence Test (primary task) and the Brooks' Matrices Test (secondary task). These two tests were administered concomitantly in both early and late learning phases of the visuomotor sequence. Overall, the groups did not differ in their ability to execute the primary task. By contrast, in accordance with the predictions, patients in Stages 2-3 of Parkinson's disease or with a cerebellar lesion failed to reveal the expected increase in performance on the secondary task seen with learning, suggesting that the latter groups of patients did not have access to the same level of residual cognitive resources to complete the matrices compared to controls. In Experiment 2, the same groups of patients and control subjects were retested again 10-18 months later. They were given four blocks of 100 trials each of the repeating sequence task, followed by a questionnaire and a self-generation task that measured their declarative knowledge of that sequence. The results revealed a long-term retention impairment only in patients who changed from Stage I to Stage II of the disease (suggesting further striatal degeneration) during the one-year interval, or who had a cerebellar lesion. By contrast, performance of the three clinical groups did not differ from controls on declarative memory tests. These findings suggest that both the striatum and the cerebellum participate to the automatization process during the late (slow) learning stage of a sequence of finger movements and that these structures also play a role in the neuronal mechanism subserving long-term retention of such a motor sequence behavior.

Adult↗

PubMed2002

Altered accumbens neural response to prediction of reward associated with place in dopamine D2 receptor knockout mice.

Midbrain dopaminergic activity seems to be important in forming the prediction of future events such as rewards. The nucleus accumbens (NAc) plays an important role in the integration of reward with motor function, and it receives dense dopamine innervation and extensive limbic and cortical afferents. Here, we examined the specific role of the dopamine D2 receptor (D2R) in mediating associative learning, locomotor activity, and regulating NAc neural responses by using D2R-knockout (KO) mice and their wild-type littermates. D2R-KO mice displayed reduced locomotor activity and slower acquisition of a place-learning task. D2R-KO eliminated the prereward inhibitory response of neurons in the NAc. In contrast, an increased number of neurons in D2R-KO mice displayed place-related activity. These results provide evidence that D2R in the NAc participates in coding for a specific type of neural response to incentive contingencies and partly in spatial learning.

Animals↗

PubMed1998

Effects of sleep loss, time of day, and extended mental work on implicit and explicit learning of sequences.

Tacit knowledge is part of many professional skills and can be studied experimentally with implicit-learning paradigms. The authors explored the effects of 2 different stressors, loss of sleep and mental fatigue, on implicit learning in a serial-response time (RT) task. In the 1st experiment, 1 night of sleep deprivation was shown to impair implicit but not explicit sequence learning. In the 2nd experiment, no impairment of both types of sequence learning was found after 1.5 hr of mental work. Serial-RT performance, in contrast, suffered from both stressors. These findings suggest that sleep deprivation induces specific risks for automatic, skill-based behavior that are not present in consciously controlled performance.

Adolescent↗

PubMedDate not supplied

Learning "what" and "how" in a human motor task.

We studied the development of implicit and of verbally declared knowledge for normal human subjects who learned an unfamiliar motor task in one learning session. The exploratory nature of motor learning and a special period for optimizing skill were followed in real time. Subjects understood the goal for task success, but they had to learn a motor strategy of what pattern of serial movements to make and the tactics of how much to scale their amplitudes and timing. We compared the time course for acquiring tactical skill with that for acquiring knowledge of strategy and of tactics, and their necessary cues. Implicit and declarative knowledge were distinguished from one another by correlating subjects' verbal self-reports with movement kinematics and their results. Implicit generation of the correct strategy and of the tactics developed in an exploratory manner from the beginning of the learning session. Implicit strategy learning soon gave way to conscious efforts, but tactical learning remained implicit until its first unambiguous verbal declaration (with one exception). First strategy declarations were voiced before those for tactics, during trial-and-error learning that did not require task success, and referred to reversing the direction of hand movements (one exception). In contrast, first declarations of tactics almost always required actual or imminent success, referred to when direction was to be reversed, and it was achieved near the top of a sigmoid learning curve that rose to tactical skill (with one exception). During the sigmoid rise, movement amplitudes and timing were optimized in a distinct manner, although tactics usually adapted thereafter to movements of more moderate speed that could still be successful.

Adult↗

PubMed2026

Artificial intelligence (AI) uses in stereotactic radiosurgery (SRS): diagnosis with brain metastasis (BM) - A systematic review.

BACKGROUND: Brain metastases (BM) are the most common intracranial tumors in adults, and stereotactic radiosurgery (SRS) has become a mainstay of management. However, several diagnostic challenges persist in the SRS pathway, particularly the differentiation of radiation necrosis (RN) from true tumor progression, which conventional MRI and even advanced imaging techniques often cannot reliably resolve. Recent advances in artificial intelligence (AI) offer the potential to address these diagnostic limitations. This systematic review synthesizes current literature on AI applications for MRI-based diagnostic decision support in BM patients undergoing SRS, with a focus on radiomics and deep learning tools for distinguishing RN from progression, classifying molecular and histologic subtypes, and predicting treatment response. METHODS: A systematic review was performed in accordance with PRISMA guidelines. PubMed, Web of Science, and Scopus were searched using a targeted query combining terms related to AI, brain metastasis, diagnosis or imaging, and SRS. After screening 483 records and applying strict inclusion and exclusion criteria, 18 studies published between 2015 and 2025 were included. Data were extracted on study design, cohort characteristics, imaging modality, AI methodology, validation strategy, and reported diagnostic performance. RESULTS: Among the 18 included studies, AI models demonstrated strong performance across diagnostic tasks in the BM-SRS pathway. The differentiation of RN from true tumor progression was the most extensively studied application, addressed by 14 of 18 studies, with reported AUCs ranging from 0.71 to 0.94. Support vector machines, random-forest ensembles, convolutional neural networks, and transformer-based multimodal architectures were widely used. The literature evolved from single-sequence radiomic classifiers in 2018 to multimodal deep learning frameworks fusing imaging with clinical and genomic data in 2025. Contrast-enhanced T1-weighted MRI was the dominant imaging input, and texture-based radiomic features (GLCM, GLSZM, GLDM, and wavelet-derived features) were the most consistently predictive. The highest-performing models reached AUCs of 0.85-0.91 through multimodal integration of imaging with clinical and genomic features, and consistently outperformed expert neuroradiologist read on matched cases. Remaining studies addressed longitudinal segmentation-based detection of local failure and adverse radiation effects, BRAF mutation status in melanoma BM, early Gamma Knife treatment response, and primary tumor histology classification, with more variable performance. CONCLUSION: AI models, particularly those integrating MRI-derived radiomic features with clinical and genomic data, show high accuracy in supporting diagnostic decisions for BM patients treated with SRS. The post-SRS differentiation of radiation necrosis from true tumor progression has reached the greatest level of maturity and is closest to clinical translation, with potential to reduce unnecessary biopsies, personalize surveillance intervals, and rationalize treatment-pathway decisions. Other diagnostic applications, including molecular subtyping and primary tumor histology classification, remain exploratory and require further multicenter validation. Integration of AI tools into multidisciplinary tumor-board workflows, combined with prospective validation and standardized reporting, will be essential to realize the full clinical benefits of AI in SRS for brain metastases.

Humans↗

PubMed1991

Changes in learning about aversive nonreward accounts for ontogeny of paradoxical appetitive reward effects in the rat pup: a mathematical model (DMOD) integrates results.

Baby rats do not show any paradoxical appetitive reward effects (e.g., faster extinction following partial than continuous reinforcement, contrast effects when large and small rewards are given) until they are at least 12-14 days old, but can learn to pattern when reward and nonreward are alternated (e.g., Amsel, 1986). These results have been puzzling, but are now successfully integrated by DMOD (Daly MODification of Rescorla and Wagner's [1972] mathematical model; Daly & Daly, 1982). It was assumed that young rats do not have the capacity to learn about aversive nonreward but slowly gain this ability between 12 and 26 days (1 parameter reflecting the rate of conditioning of aversive nonreward, beta 1 for Vav, is increased from 0 to .15 beginning at 12 days). This theoretical integration has implications for understanding behavioral and neurological development of altricial organisms, and effects of neurological damage and toxic substances.

Aging↗

PubMed2003

Event-related correlations in learning impaired children during A hybrid go/no-go choice reaction visual-motor task.

One hundred sixty-nine learning impaired (LI) and 71 non-learning impaired (NLI) children underwent a hybrid go/no-go choice reaction time visual-motor task to study the behavioral and physiological fundamentals of learning disorders. A left button was pressed for Left Arrow (LA) stimuli, a right for Right Arrow (RA) stimuli, none (no-go) for a non-directional arrow. Stimulus specific visual evoked potentials were formed and, with PZ as index electrode, were lag-correlated to frontal electrodes to form Event-Related Correlations (ERC). Exploratory t-statistic significance probability maps (t-SPM) were used to define regions of interest (ROI). Behaviorally, there was a right-hand advantage over the left in the NLI group, but less in the LI group. Electrophysiologically, RA and LA conditions increased correlation between visual areas (PZ) and contralateral frontal areas (F3 and F4). A unilateral ROI, at electrode FC1, also preceded both left- and right-handed responses. Neurobehaviorally, increased visual-motor correlation was associated with better performance, especially for the left hemisphere, at F3 and FC1. Surprisingly, visual-motor correlations were not associated with performance for the NLI group in the RA and no-go condition. Our data support previously reported difficulties of learning impaired children in low-level information processing. Furthermore, we hypothesize that LI, in contrast to NLI children, demonstrate difficulty in automatizing routine tasks.

Brain↗

PubMed1985

The effects of time compression on the auditory processing abilities of learning disabled children.

This study measured the ability of ten 8- and ten 12-yr-old learning disabled (LD) children of normal intelligence (WISC-R) to discriminate phonemic contrasts in sentential stimuli (Subtest 13 of the Carrow Auditory Visual Abilities Test) presented at a 50% time-compression rate. Their group responses were compared statistically to similar data gathered earlier (May et al, J. Aud. Res., 1984, 24, 205-211) from 6-, 8-, and 10-yr-old normal children and young adults. LD Ss exhibited auditory processing capacities reminiscent of an earlier level of operation (e.g., the group of LD Ss with mn age of 12.8 yrs yielded group performance equivalent to that of normal 6- and 8-yr-olds), and also manifested marked differences in their feature- and frequency-processing abilities. These data indicate that contributing to the learning difficulties of LD children may very well be delays in auditory development and anomalies in auditory-feature processing.

Age Factors↗