Common mechanisms of human perceptual and motor learning
ABSTRACT The adult mammalian brain has a remarkable capacity to learn in both the perceptual and motor domains through the formation and consolidation of memories. Such practice-enabled procedural learning results in perceptual and motor skill improvements. Here, we examine evidence supporting the notion that perceptual and motor learning in humans exhibit analogous properties, including similarities in temporal dynamics and the interactions between primary cortical and higher-order brain areas. These similarities may point to the existence of a common general mechanism for learning in humans.
- SourceAvailable from: Elisa Santandrea
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- "Incidentally, one should also note that while the orientation discrimination task employed by Schiltz et al. (1999) tapped a form of slow-incremental learning, occurring over the course of many sessions and thousands of trials, this was not the case in the study of Vaina et al. (1998), where learning at the global motion discrimination task was characterized within minutes of performance and tens-to-few hundreds of trials (fast learning). It is widely maintained that fast and slow perceptual learning phenomena represent distinct forms of learning, presumably tapping different sub-components of the learning process and perhaps reflecting changes of a different nature and occurring within different brain circuits (Censor et al., 2012; Karni & Bertini, 1997). In this regard we underscore that the results presented here indicate that the cerebellum is engaged for visual perceptual learning occurring on both time scales. "
ABSTRACT: Visual perceptual learning is widely assumed to reflect plastic changes occurring along the cerebro-cortical visual pathways, including at the earliest stages of processing, though increasing evidence indicates that higher-level brain areas are also involved. Here we addressed the possibility that the cerebellum plays an important role in visual perceptual learning. Within the realm of motor control, the cerebellum supports learning of new skills and re-calibration of motor commands when movement execution is consistently perturbed (adaptation). Growing evidence indicates that the cerebellum is also involved in cognition and mediates forms of cognitive learning. Therefore, the obvious question arises whether the cerebellum might play a similar role in learning and adaptation within the perceptual domain. We explored a possible deficit in visual perceptual learning (and adaptation) in patients with cerebellar damage using variants of a novel motion extrapolation, psychophysical paradigm. Compared to their age- and gender-matched controls, patients with focal damage to the posterior (but not the anterior) cerebellum showed strongly diminished learning, in terms of both rate and amount of improvement over time. Consistent with a double-dissociation pattern, patients with focal damage to the anterior cerebellum instead showed more severe clinical motor deficits, indicative of a distinct role of the anterior cerebellum in the motor domain. The collected evidence demonstrates that a pure form of slow-incremental visual perceptual learning is crucially dependent on the intact cerebellum, bearing the notion that the human cerebellum acts as a learning device for motor, cognitive and perceptual functions. We interpret the deficit in terms of an inability to fine-tune predictive models of the incoming flow of visual perceptual input over time. Moreover, our results suggest a strong dissociation between the role of different portions of the cerebellum in motor vs. non-motor functions, with only the posterior lobe being responsible for learning in the perceptual domain.Cortex 09/2014; 58. DOI:10.1016/j.cortex.2014.04.017 · 6.04 Impact Factor
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- "This result showed that learning difficulty in children with dyslexia was not confined to abstract rule-based knowledge learning (Folia et al., 2008) and association learning (Li et al., 2009) but also occurred in learning to discriminate very basic visual features; this extended the understanding of learning deficits in individuals with dyslexia to basic perceptual learning. Further experimentation needs to clarify whether it is a separate type of learning difficulty or if it is a deficit associated with implicit motor sequence learning rooted in a common mechanism (Censor et al., 2012). Given that the SOA values in TDT are considered as time thresholds within which observers are able to capture features of objects and form object representation (Bergen & Julesz, 1983; Sagi & Julesz, 1985), the significantly higher SOAs for readers with dyslexia therefore demonstrated that they were unable to extract the visual features of the presented stimuli as efficiently as the controls. "
ABSTRACT: Learning to read involves discriminating between different written forms and establishing connections with phonology and semantics. This process may be partially built upon visual perceptual learning, during which the ability to process the attributes of visual stimuli progressively improves with practice. The present study investigated to what extent Chinese children with developmental dyslexia have deficits in perceptual learning by using a texture discrimination task, in which participants were asked to discriminate the orientation of target bars. Experiment l demonstrated that, when all of the participants started with the same initial stimulus-to-mask onset asynchrony (SOA) at 300 ms, the threshold SOA, adjusted according to response accuracy for reaching 80% accuracy, did not show a decrement over 5 days of training for children with dyslexia, whereas this threshold SOA steadily decreased over the training for the control group. Experiment 2 used an adaptive procedure to determine the threshold SOA for each participant during training. Results showed that both the group of dyslexia and the control group attained perceptual learning over the sessions in 5 days, although the threshold SOAs were significantly higher for the group of dyslexia than for the control group; moreover, over individual participants, the threshold SOA negatively correlated with their performance in Chinese character recognition. These findings suggest that deficits in visual perceptual processing and learning might, in part, underpin difficulty in reading Chinese. Copyright © 2014 John Wiley & Sons, Ltd.Dyslexia 08/2014; 20(3). DOI:10.1002/dys.1475 · 1.12 Impact Factor
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- "Motor skill learning is the process of improving the spatial and/ or temporal accuracy of a motor skill through motor practice. Motor practice is essential for learning motor skills because it is during practice (online learning) that the nervous system encodes both perceptual and procedural information, which is later used for the elaboration of motor memories (Censor et al., 2012). However, the nervous system does not stop processing information with the end of practice. "
ABSTRACT: Declines in the ability to learn motor skills in older adults are commonly attributed to deficits in the encoding of sensorimotor information during motor practice. We investigated whether aging also impairs motor memory consolidation by assessing the susceptibility to memory interference and off-line gains in motor skill learning after practice in children, young, and older adults. Subjects performed a ballistic task (A) followed by an accuracy-tracking task (B) designed to disrupt the consolidation of A. Retention tests of A were performed immediately and 24 hours after B. Older adults showed greater susceptibility to memory interference and no off-line gains in motor skill learning. Performing B produced memory interference and reduced off-line gains only in the older group. However, older adults also showed deficits in memory consolidation independent of the interfering effects of B. Age-related declines in motor skill learning are not produced exclusively by deficits in the encoding of sensorimotor information during practice. Aging also increases the susceptibility to memory interference and reduces off-line gains in motor skill learning after practice.Neurobiology of aging 03/2014; 35(8). DOI:10.1016/j.neurobiolaging.2014.02.022 · 4.85 Impact Factor