Understanding Of Motor Learning Research Articles

Differential effects of reward and punishment on reinforcement-based motor learning and generalization.

Reward and punishment have long been recognized as potent modulators of human behavior. Although reinforcement learning is a significant motor learning process, the exact mechanisms underlying how the brain learns movements through reward and punishment are not yet fully understood. Beyond the memory of specific examples, investigating the ability to generalize to new situations offers a better understanding of motor learning. This study hypothesizes that reward and punishment engage qualitatively different motivational systems with different neurochemical and neuroanatomical substrates, which would have differential effects on reinforcement-based motor learning and generalization. To test this hypothesis, two groups of participants learn a motor task in one direction and then relearn the same task in a new direction, receiving only performance-based reward or punishment score feedback. Our findings support our hypothesis, showing that reward led to slower learning but promoted generalization. On the other hand, punishment led to faster learning but impaired generalization. These behavioral differences may be due to different tendencies of movement variability in each group. The punishment group tended to explore more actively than the reward group during the initial learning phase, possibly due to loss aversion. In contrast, the reward group tended to explore more actively than the initial learning phase during the generalization test phase, seemingly recalling back the strategy that led to reward. These results suggest that reward and punishment may engage different neural mechanisms during reinforcement-based motor learning and generalization, with important implications for practical applications such as sports training and motor rehabilitation.

Statistical determinants of visuomotor adaptation along different dimensions during naturalistic 3D reaches

Neurorehabilitation in patients suffering from motor deficits relies on relearning or re-adapting motor skills. Yet our understanding of motor learning is based mostly on results from one or two-dimensional experimental paradigms with highly confined movements. Since everyday movements are conducted in three-dimensional space, it is important to further our understanding about the effect that gravitational forces or perceptual anisotropy might or might not have on motor learning along all different dimensions relative to the body. Here we test how well existing concepts of motor learning generalize to movements in 3D. We ask how a subject’s variability in movement planning and sensory perception influences motor adaptation along three different body axes. To extract variability and relate it to adaptation rate, we employed a novel hierarchical two-state space model using Bayesian modeling via Hamiltonian Monte Carlo procedures. Our results show that differences in adaptation rate occur between the coronal, sagittal and horizontal planes and can be explained by the Kalman gain, i.e., a statistically optimal solution integrating planning and sensory information weighted by the inverse of their variability. This indicates that optimal integration theory for error correction holds for 3D movements and explains adaptation rate variation between movements in different planes.

Potential and Limitations of Feedback-Supported Gait Retraining in Users of Lower Limb Prostheses

The outcomes of prosthetic rehabilitation after lower limb loss are, in large part, affected by the effectiveness of the provided gait retraining. The noted prevalence of adverse long-term effects, such as further joint and muscle degeneration, suggests that traditional rehabilitation programs have limitations. Recent advances in technology and in the understanding of motor learning promise the potential for better gait retraining interventions. This article reviews current literature on systems and methodologies of improving gait parameters in those with lower limb prostheses via exercise programs and various biofeedback systems. A total of 13 articles were included in the qualitative analysis. Findings indicate that many of the investigated systems are able to effectively analyze and change gait in the target population, but there remain considerable gaps in the knowledge. It has been noted that feedback modalities and dosage must be customized based on patient characteristics and rehabilitation goals, yet there is currently not enough published evidence to inform such customization.

Individual differences in motor skill learning: Past, present and future.

Humans vary considerably in their ability to perform and learn new motor skills. In addition, they respond to different performance and practice conditions in varying ways. Historically, experimental psychologists have characterized these differences as 'experimental noise', yet for those who embrace differential psychology, the study of individual differences promises to deepen insights into the processes that mediate motor control and learning. In this paper, we highlight what we know about predicting motor learning based on individual difference characteristics and renew a call made by Lee Cronbach several decades ago to combine the methodologies used by experimental and differential psychologists to further our understanding of how to promote motor learning. The paper provides a brief historical overview of research on individual differences and motor learning followed by a systematic review of the last 20years of research on this issue. The paper ends by highlighting some of the methodological challenges associated with conducting research on individual differences, as well as providing suggestions for future research. The study of individual differences has important implications for furthering our understanding of motor learning and when tailoring interventions for diverse learners at different stages of practice.

Learning in the educational landscapes of juggling, unicycling, and dancing

ABSTRACT Background Movement learning has been thoroughly investigated in the area of motor learning research. Although existing studies have contributed to a substantial understanding of motor learning, many have been criticized for their reliance on experimental designs where learning is decontextualized, simplified, and investigated in laboratory settings. Researchers have claimed that motor learning theories emanating from such studies are grounded on a dualistic approach to learning and that the theories are often difficult to apply in educational settings. More pedagogically-inspired studies of movement education have investigated movement learning, but the majority of this research has focused on teaching. This focus has left the process of learning somewhat unexplored. There is thus a need for empirical studies that investigate students’ learning processes in educational contexts. Purpose The aim of this study is to explore, analyze, and understand how learners develop their movement capability when they are provided opportunities to choose different ways of learning activities. Theory and method We combine Ryle’s and Polanyi’s ideas concerning practical knowledge with Hirst’s and Carlgren’s idea of knowing as familiarity with a landscape. Ryle’s notion of ‘intelligent practice’ is used in thinking of the kinds of actions individuals might engage in. Characterizing features of intelligent practice includes being sensitive to one’s own actions, changing one’s behavior as the result of mistakes, and profiting from the examples of others. We understand the development of movement capability as continuously expanding one’s ability to discern nuances and their relationships. This perspective fits well with Polanyi’s notion of focal and subsidiary awareness. Taken together Ryle’s, Polanyi’s, Hirst’s, and Carlgren’s notions related to knowing and learning inform our perspective on learning in movement education. Based on this perspective on knowing and learning, an action-oriented study was conducted. The researchers created pedagogical modules and collaborated with teachers and university educators to develop learning sequences in line with the needs of their respective groups. With each group, we produced data based on video and field notes. Three successful learners were chosen and followed in-depth with regard to their learning actions. Findings The findings show the learners’ varying ways of exploring a movement landscape as playing around in the terrain; checking the map; investigating one chosen path; occupying the vantage point; imitating and actively observing. The findings suggest that oscillating between varying kinds of learning actions is an additional characterizing feature of ‘intelligent practice.’ Discussion The findings demonstrate how the learning of movement capability could occur when providing opportunities to engage in ‘intelligent practice’ while at the same time directing their focal awareness toward what is most beneficial to them. Opposed to a ‘step-by-step’ approach to learning, the learners come to know a movement landscape as extending one’s capability to discern and differentiate details, nuances, and their relationships. The findings suggest that it may be beneficial for learners to get opportunities to oscillate between different kinds of learning actions.

Lessons about Motor Learning: How Is Motor Learning Taught in Physical Therapy Programmes Across Canada?

Purpose: This article describes the content of and delivery methods for motor learning (ML) education and the attitudes and beliefs of instructors with regard to how ML is taught in Canadian physical therapy (PT) programmes. Method: A qualitative descriptive design was employed, using an online questionnaire and semi-structured telephone interviews. A descriptive content analysis was used to develop codes and themes. An online search of PT programme Web sites was conducted to supplement missing data and collect information from schools that did not participate in the online questionnaire or interview. Results: Eight individuals representing seven schools completed the questionnaire; six of the eight also completed the interview. Responses conveyed the fact that ML content was fairly consistent across schools and was predominantly situated in the neurological curriculum. Schools differed in the delivery methods used for clinical application of ML content. Respondents believed that ML underlies PT practice and should be integrated throughout the programme. Conclusion: Current instruction may deliver adequate ML content but may not provide optimal opportunities to apply ML principles in a clinical context. Continuing education emerged as one suggestion for remediating clinicians' knowledge-practice gap and facilitating student learning on placement. Only half the eligible PT schools participated, and all were English-language programmes; thus, the findings may not be generalizable to all Canadian programmes. Future work should explore how ML can be integrated into the PT curriculum to promote the application of ML principles across different fields. Students' perspectives on their understanding of ML and ML principles and self-efficacy for entry to practice should also be explored.

P 68 Novel control concepts and motor re-learning strategy in neurorehabilitation – practically-oriented approach

Background and motivation Persons suffering from functional impairment, due to cerebral palsy, stroke, or Parkinson’s, often have not reached their full potential for recovery which often is a reason for injures and loss of life due to fall. Motor skill learning and retention of motor skills can be enhanced if a patient assumes control over practice conditions, e.g. timing of exercise instructions and feedback. In our study, we follow a novel conceptual framework ( Despotova and Kiriazov, 2015 ) for optimal control learning of goal-directed motion tasks, like reaching, standing up and walking. Currently we are designing an adequate control strategy for posture stabilization tasks, too. ( Despotova et al., xxxx ). Generally speaking our research on neurorehabilitation is based on underlying principles and novel concepts of neurophysiology, multi-segmental dynamics, optimal control theory, and control learning (CL). Methods Our approach is based on the real dynamics and its control concepts are biologically plausible. Moreover, the proposed CL approach has the necessary mathematical guarantees for its feasibility and convergence. For dynamic goal-directed movements, we can apply an efficient CL scheme which has the following main stages: • Choose a set of appropriate test control functions • Define the most relevant pairs of control parameters and controlled outputs • Perform control parameter optimization in training exercises Of primary importance is to define a set of variables that best characterize the dynamic performance in the required motion task. We make corrections in the control parameters until reach the target, applying efficient, natural learning algorithms. Results Our control concepts have been verified in numerous computer simulations. The proposed approach is successfully applied using human body models with 2, 3, 4 and 6 degrees of freedom representing reaching ( Fig. 1 ), standing up, and walking motion in sagittal plane, Fig. 2 . In Fig. 1 , the convergence to the target in a reaching motion task is achieved after a very small number of trials. The efficiency of our CL algorithm is confirmed also in a real body experiment – healthy subject performing fast reaching (ballistic-like) movements. Special attention in our current research is devoted to the challenging problem of CL in the real, three-dimensional human locomotion. We can perform proper decomposition of this complex motion task into several goal-directed movements and apply the proposed CL scheme for each of them. Discussion We believe that the proposed approach can be used to rebuild the so-called internal models (cortical reorganization) by proper training procedures. The work outlined here can provide a fundamental understanding of motor learning and may lead to the development of optimal strategies for efficient neuro-muscular rehabilitation. In addition we have found that our approach is very promising and could be efficiently applied to the more complex, human/robot systems. Various assistive devices may be used for restoration of human movement functionality, such as passive and active orthoses, robotic exoskeletons, EMG, FES, brain-computer interfaces (BCI).

The Role of Variability in Motor Learning.

Trial-to-trial variability in the execution of movements and motor skills is ubiquitous and widely considered to be the unwanted consequence of a noisy nervous system. However, recent studies have suggested that motor variability may also be a feature of how sensorimotor systems operate and learn. This view, rooted in reinforcement learning theory, equates motor variability with purposeful exploration of motor space that, when coupled with reinforcement, can drive motor learning. Here we review studies that explore the relationship between motor variability and motor learning in both humans and animal models. We discuss neural circuit mechanisms that underlie the generation and regulation of motor variability and consider the implications that this work has for our understanding of motor learning.

Evolving Models of Pavlovian Conditioning: Cerebellar Cortical Dynamics in Awake Behaving Mice.

SummaryThree decades of electrophysiological research on cerebellar cortical activity underlying Pavlovian conditioning have expanded our understanding of motor learning in the brain. Purkinje cell simple spike suppression is considered to be crucial in the expression of conditional blink responses (CRs). However, trial-by-trial quantification of this link in awake behaving animals is lacking, and current hypotheses regarding the underlying plasticity mechanisms have diverged from the classical parallel fiber one to the Purkinje cell synapse LTD hypothesis. Here, we establish that acquired simple spike suppression, acquired conditioned stimulus (CS)-related complex spike responses, and molecular layer interneuron (MLI) activity predict the expression of CRs on a trial-by-trial basis using awake behaving mice. Additionally, we show that two independent transgenic mouse mutants with impaired MLI function exhibit motor learning deficits. Our findings suggest multiple cerebellar cortical plasticity mechanisms underlying simple spike suppression, and they implicate the broader involvement of the olivocerebellar module within the interstimulus interval.

Brain plasticity and rehabilitation in stroke patients.

In recent years, our understanding of motor learning, neuroplasticity and functional recovery after the occurrence of brain lesion has grown significantly. Novel findings in basic neuroscience have provided an impetus for research in motor rehabilitation. The brain reveals a spectrum of intrinsic capacities to react as a highly dynamic system which can change the properties of its neural circuits. This brain plasticity can lead to an extreme degree of spontaneous recovery and rehabilitative training may modify and boost the neuronal plasticity processes. Animal studies have extended these findings, providing insight into a broad range of underlying molecular and physiological events. Neuroimaging studies in human patients have provided observations at the systems level that often parallel findings in animals. In general, the best recoveries are associated with the greatest return toward the normal state of brain functional organization. Reorganization of surviving central nervous system elements supports behavioral recovery, for example, through changes in interhemispheric lateralization, activity of association cortices linked to injured zones, and organization of cortical representational maps. Evidence from animal models suggests that both motor learning and cortical stimulation alter intracortical inhibitory circuits and can facilitate long-term potentiation and cortical remodeling. Current researches on the physiology and use of cortical stimulation animal models and in humans with stroke related hemiplegia are reviewed in this article. In particular, electromyography (EMG) -controlled electrical muscle stimulation improves the motor function of the hemiparetic arm and hand. A multi-channel near-infrared spectroscopy (NIRS) studies in which the hemoglobin levels in the brain were non-invasively and dynamically measured during functional activity found that the cerebral blood flow in the injured sensory-motor cortex area is greatest during an EMG-controlled FES session. Only a few idea is, however, known for the optimal timing of the different processes and therapeutic interventions and for their interactions in detail. Finding optimal rehabilitation paradigms requires an optimal organization of the internal processes of neural plasticity and the therapeutic interventions in accordance with defined plastic time windows. In this review the mechanisms of spontaneous plasticity after stroke and experimental interventions to enhance plasticity are summarized, with an emphasis on functional electrical stimulation therapy.

Rehabilitation with Functional Electrical Stimulation in Stroke Patients

In recent years, our understanding of motor learning, neuroplasticity and functional recovery after the occurrence of brain lesion has grown significantly. New findings in basic neuroscience have provided an impetus for research in motor rehabilitation. Several prospective studies have shown that repeated motor practice and motor activity in a real world environment have a favorable effect on motor recovery in stroke patients. Electrical stimulation can be applied in a variety of ways to the hemiparetic upper extremity following a stroke. In particular, electromyography (EMG)- triggered electrical muscle stimulation improves the motor function of the hemiparetic arm and hand. Triggered electrical stimulation is reported to be more effective than non-triggered electrical stimulation in facilitating upper extremity motor recovery after stroke. EMG-controlled functional electrical stimulation (FES) induces greater muscle contraction by electrical stimulation that is in proportion to voluntary integrated EMG signals. EMG-controlled FES and motor point block for antagonist muscles have been applied as a new hybrid FES therapy in an outpatient rehabilitation clinic for patients with stroke with good result. Daily EMG-controlled FES home-program therapy with novel equipment has been shown to effectively improve wrist, finger extension, and shoulder flexion. Combined modulation of voluntary movement, proprioceptive sensory feedback, and electrical stimulation might play an important role in improving impaired sensory-motor integration by EMG-controlled FES therapy. A multi-channel near-infrared spectroscopy (NIRS) studies in which the hemoglobin levels in the brain were non-invasively and dynamically measured during functional activity found that the cerebral blood flow in the injured sensory-motor cortex area is greater during a EMG-controlled FES session than during simple active movement or simple electrical stimulation. Nevertheless, evidence-based strategies for FES rehabilitation are more and more available, particularly for patients suffering from hemiparesis.

Neurorehabilitation with New Functional Electrical Stimulation for Hemiparetic Upper Extremity in Stroke Patients

In recent years, our understanding of motor learning, neuroplasticity, and functional recovery after the occurrence of brain lesion has grown significantly. New findings in basic neuroscience have stimulated research in motor rehabilitation. Repeated motor practice and motor activity in a real-world environment have been identified in several prospective studies as favorable for motor recovery in stroke patients. Electrical stimulation can be applied in a variety of ways to the hemiparetic upper extremity following stroke. In this paper, an overview of current research into clinical and therapeutic applications of functional electrical stimulation (FES) is presented. In particular, electromyography (EMG)-initiated electrical muscle stimulation--but not electrical muscle stimulation alone--improves the motor function of the hemiparetic arm and hand. Triggered electrical stimulation is reported to be more effective than untriggered electrical stimulation in facilitating upper extremity motor recovery following stroke. Power-assisted FES induces greater muscle contraction by electrical stimulation in proportion to the voluntary integrated EMG signal picked up, which is regulated by a closed-loop control system. Power-assisted FES and motor point block for antagonist muscles have been applied with good results as a new hybrid FES therapy in an outpatient rehabilitation clinic for patients with stroke. Furthermore, a daily home program therapy with power-assisted FES using new equipment has been able to effectively improve wrist and finger extension and shoulder flexion. Proprioceptive sensory feedback might play an important role in power-assisted FES therapy. Although many physiotherapeutic modalities have been established, conclusive proof of their benefit and physiological models of their effects on neuronal structures and processes are still missing. A multichannel near-infrared spectroscopy study to noninvasively and dynamically measure hemoglobin levels in the brain during functional activity has shown that cerebral blood flow in the sensory-motor cortex on the injured side is higher during a power-assisted FES session than during simple active movement or simple electrical stimulation. Nevertheless, evidence-based strategies for motor rehabilitation are more easily available, particularly for patients with hemiparesis.

Evidence-based physiotherapeutic concepts for improving arm and hand function in stroke patients

In recent years, our understanding of motor learning, neuroplasticity and functional recovery after the occurrence of brain lesion has grown significantly. New findings in basic neuroscience provided stimuli for research in motor rehabilitation. Repeated motor practice and motor activity in a real world environment have been identified in several prospective studies as favorable for motor recovery in stroke patients. EMG initiated electrical muscle stimulation -- but not electrical muscle stimulation alone -- improves motor function of the centrally paretic arm and hand. Although a considerable number of physiotherapeutic "schools" has been established, a conclusive proof of their benefit and a physiological model of their effect on neuronal structures and processes are still missing. Nevertheless, evidence-based strategies for motor rehabilitation are more and more available, particularly for patients suffering from central paresis.