Combining unassisted and robot-guided practice benefits motor learning for a golf putting task

Robotic guidance has been employed with limited effectiveness in neurologically intact and patient populations. For example, our lab has effectively used robotic guidance to acutely improve movement smoothness of a discrete trajectory without influencing movement endpoint distributions. The purpose of the current study was to investigate the efficacy of combining robotic guidance and unassisted trials in the learning of a golf putting task. Participants completed a pre-test, an acquisition phase, and an immediate and delayed (24-hour) post-test. During the pre-test, kinematic data from the putter was converted into highly accurate, consistent, and smooth trajectories delivered by a robot arm. During acquisition, three groups performed putts towards three different targets with robotic guidance on either 0%, 50%, or 100% of acquisition trials. Only the 50% guidance group statistically reduced both the ball endpoint distance and variability between the pre-test and the immediate or 24-hr post-test. The results of the 50% guidance group yielded seminal evidence that combining both unassisted and robotic guidance trials (i.e., mixed practice) could facilitate at least short-term motor learning for a golf putting task. Such work is relevant to incorporating robotic guidance in sport skills and other practical areas (e.g., rehabilitation)

Unlocking Access to Health Care: A Federalist Approach to Reforming Occupational Licensing

Several features of the existing occupational licensing system impede access to health care without providing appreciable protections for patients. Licensing restrictions prevent health care providers from offering services to the full extent of their competency, obstruct the adoption of telehealth, and deter foreign-trained providers from practicing in the United States. Scholars and policymakers have proposed a number of reforms to this system over the years, but these proposals have had a limited impact for political and institutional reasons. Still, there are grounds for optimism. In recent years, the federal government has taken a range of initial steps to reform licensing requirements for health care providers, and these steps have the potential to improve access to health care. Together, they illustrate a federalist approach to licensing reform, in which the federal government encourages the states to reform their licensing regimes, while largely preserving states’ control over the system. These steps include: (1) easing federal licensing restrictions for health care providers in certain areas where the federal government possesses regulatory authority; (2) creating incentives for states and professional bodies to experiment with reforms; (3) intensifying the Federal Trade Commission’s focus on licensing boards’ anti-competitive conduct; and (4) generating additional pressure for state-level reforms through expanding health insurance and promoting delivery system reforms under the Affordable Care Act. This article argues that a federalist approach represents the most promising path toward reforming occupational licensing in health care. Federal intervention in licensing is necessary, due to states’ lack of incentives to experiment with licensing reforms, the externalities of their licensing regimes, and their inability to resolve their own collective action problems. Nevertheless, large-scale federal preemption of state licensing laws is unlikely, due to a combination of interest group politics, Congress’s tendency toward incrementalism, and its reliance on the states to administer federal policies. A federalist approach also has functional advantages over outright federal preemption: it allows for more experimentation in constructing new licensing regimes, and it enables the federal government to take advantage of states’ institutional expertise in regulating occupations. Finally, this approach presents a model for how the federal government can play a constructive role in occupational licensing in other fields besides health care, and in other areas of state regulatory policy

Humans versus robots: Converting golf putter trajectories for robotic guidance

Robotic devices are used to provide physical guidance when teaching different movements. To advance our knowledge of robotic guidance in training complex movements, this investigation tested different kinematic data filtering methods of individual’s golf putts to convert them into trajectories to be employed by a robot arm. The purpose of the current study was to identify a simple filtering method to aptly replicate participants’ individual golf putter trajectories which could be used by the robot to execute them with greater consistency and accuracy than their human counterpart. Participants putted towards 3 targets where three-dimensional data of the putter’s head was filtered and then fitted by using one- or two-dimensions of the participant’s putter head trajectories. As expected, both filtering methods employed with the robot outperformed the human participants in ball endpoint accuracy and consistency. Further, after comparing the filtered to the human participants trajectories, the two-dimensional method best replicated the kinematic features of human participants natural putter trajectory, while the one-dimensional method failed to replicate participant’s backstroke position. This investigation indicates that a two-dimensional filtering method, using Y-forward and Z-vertical position data, can be used to create accurate, consistent, and smooth trajectories delivered by a robot arm

Two Neural Circuits to Point Towards Home Position After Passive Body Displacements

International audienceA challenge in motor control research is to understand the mechanisms underlying the transformation of sensory information into arm motor commands. Here, we investigated these transformation mechanisms for movements whose targets were defined by information issued from body rotations in the dark (i.e., idiothetic information). Immediately after being rotated, participants reproduced the amplitude of their perceived rotation using their arm (Experiment 1). The cortical activation during movement planning was analyzed using electroencephalography and source analyses. Task-related activities were found in regions of interest (ROIs) located in the prefrontal cortex (PFC), dorsal premotor cortex, dorsal region of the anterior cingulate cortex (ACC) and the sensorimotor cortex. Importantly, critical regions for the cognitive encoding of space did not show significant task-related activities. These results suggest that arm movements were planned using a sensorimotor-type of spatial representation. However, when a 8 s delay was introduced between body rotation and the arm movement (Experiment 2), we found that areas involved in the cognitive encoding of space [e.g., ventral premotor cortex (vPM), rostral ACC, inferior and superior posterior parietal cortex (PPC)] showed task-related activities. Overall, our results suggest that the use of a cognitive-type of representation for planning arm movement after body motion is necessary when relevant spatial information must be stored before triggering the movement

Susceptibility to the fusion illusion is modulated during both action execution and action observation

Many researchers have proposed that when an individual observes the actions of another individual, the observer simulates the action using many of the same neural areas that are involved in action production. The present study was designed to test this simulation hypothesis by comparing the perception of multisensory stimuli during both the execution and observation of an aiming action. The present work used the fusion illusion - an audio-visual illusion in which two visual stimuli presented with one auditory stimulus are erroneously perceived as being one visual stimulus. Previous research has shown that, during action execution, susceptibly to this illusion is reduced early in the execution of the movement when visual information may be more highly weighted than other sensory information. We sought to determine whether or not a non-acting observer of an action showed a similar reduction in susceptibility to the fusion illusion. Participants fixated a target and either executed or observed a manual aiming movement to that target. Audiovisual stimuli were presented at 0, 100, or 200 ms relative to movement onset and participants reported the number of perceived flashes after the movement was completed. Analysis of perceived flashes revealed that participants were less susceptible to the fusion illusion when the stimuli were presented early (100 ms) relative to later in the movement (200 ms). Critically, this pattern emerged in both execution and observation tasks. These findings support the hypothesis that observers simulate the performance of the actor and experience comparable real-time alterations in multisensory processing

Bi-allelic Loss-of-Function CACNA1B Mutations in Progressive Epilepsy-Dyskinesia.

The occurrence of non-epileptic hyperkinetic movements in the context of developmental epileptic encephalopathies is an increasingly recognized phenomenon. Identification of causative mutations provides an important insight into common pathogenic mechanisms that cause both seizures and abnormal motor control. We report bi-allelic loss-of-function CACNA1B variants in six children from three unrelated families whose affected members present with a complex and progressive neurological syndrome. All affected individuals presented with epileptic encephalopathy, severe neurodevelopmental delay (often with regression), and a hyperkinetic movement disorder. Additional neurological features included postnatal microcephaly and hypotonia. Five children died in childhood or adolescence (mean age of death: 9 years), mainly as a result of secondary respiratory complications. CACNA1B encodes the pore-forming subunit of the pre-synaptic neuronal voltage-gated calcium channel Cav2.2/N-type, crucial for SNARE-mediated neurotransmission, particularly in the early postnatal period. Bi-allelic loss-of-function variants in CACNA1B are predicted to cause disruption of Ca2+ influx, leading to impaired synaptic neurotransmission. The resultant effect on neuronal function is likely to be important in the development of involuntary movements and epilepsy. Overall, our findings provide further evidence for the key role of Cav2.2 in normal human neurodevelopment.MAK is funded by an NIHR Research Professorship and receives funding from the Wellcome Trust, Great Ormond Street Children's Hospital Charity, and Rosetrees Trust. E.M. received funding from the Rosetrees Trust (CD-A53) and Great Ormond Street Hospital Children's Charity. K.G. received funding from Temple Street Foundation. A.M. is funded by Great Ormond Street Hospital, the National Institute for Health Research (NIHR), and Biomedical Research Centre. F.L.R. and D.G. are funded by Cambridge Biomedical Research Centre. K.C. and A.S.J. are funded by NIHR Bioresource for Rare Diseases. The DDD Study presents independent research commissioned by the Health Innovation Challenge Fund (grant number HICF-1009-003), a parallel funding partnership between the Wellcome Trust and the Department of Health, and the Wellcome Trust Sanger Institute (grant number WT098051). We acknowledge support from the UK Department of Health via the NIHR comprehensive Biomedical Research Centre award to Guy's and St. Thomas' National Health Service (NHS) Foundation Trust in partnership with King's College London. This research was also supported by the NIHR Great Ormond Street Hospital Biomedical Research Centre. J.H.C. is in receipt of an NIHR Senior Investigator Award. The research team acknowledges the support of the NIHR through the Comprehensive Clinical Research Network. The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR, Department of Health, or Wellcome Trust. E.R.M. acknowledges support from NIHR Cambridge Biomedical Research Centre, an NIHR Senior Investigator Award, and the University of Cambridge has received salary support in respect of E.R.M. from the NHS in the East of England through the Clinical Academic Reserve. I.E.S. is supported by the National Health and Medical Research Council of Australia (Program Grant and Practitioner Fellowship)

A first update on mapping the human genetic architecture of COVID-19

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The Role of Visuomotor Regulation Processes on Perceived Audiovisual Events

Recent evidence suggests audiovisual perception changes as one engages in action. Specifically, if an audiovisual illusion comprised of 2 flashes and 1 beep is presented during the high velocity portion of upper- limb movements, the influence of the auditory stimuli is subdued. The goal of this thesis was to examine if visuomotor regulation processes that rely on information obtained when the limb is traveling at a high velocity could explain this perceptual modulation. In the present study, to control for engagement in visuomotor regulation processes, vision of the environment was manipulated. In conditions without vision of the environment, participants did not show the noted modulation of the audiovisual illusion. Also, analysis of the movement trajectories and endpoint precision revealed that movements without vision were less controlled than movements performed with vision. These results suggest that engagement in visuomotor regulation processes can influence perception of certain audiovisual events during goal-directed action.MAS

Examining the sensorimotor integration processes prior to and during movements to somatosensory targets

La littérature sur les processus d’intégration multisensoriels (i.e., transformations sensorimotrice) avant et pendant des mouvements volontaires ont principalement utilisé des cibles visuelles. Considérant que la modalité d’une cible influence le cadre de référence utilisé pour contrôler un mouvement volontaire, l’objectif principal des trois expériences de la présente thèse était d’examiner ces processus de transformations sensorimotrices, et ce, spécifiquement pour des mouvements vers un cible somatosensorielle. Les deux premières expériences ont examiné les transformations sensorimotrices pendant la planification du mouvement. L’objectif de la troisième expérience était d’examiner les transformations sensorimotrices utilisée pour le contrôle du mouvement vers une cible somatosensorielle. Les résultats des deux premières expériences indiquent que des même des signaux auditifs peuvent faciliter l’utilisation d’un cadre de référence visuel du corps pour transformer la position de cibles somatosensorielles. Ces processus de transformation pourraient nécessiter des processus supplémentaires et engagent clairement des réseaux corticaux visuels et visuomoteurs. De plus, les résultats de la troisième expérience indique que des corrections apportées aux mouvements vers des cibles somatosensorielles perturbées prennent moins de temps pour être initiées en plus d’être plus efficaces et précises que des corrections apportées aux mouvement vers des cibles visuelles. De plus, cette troisième expérience indique que des cibles somatosensorielles ne sont pas nécessairement transformées dans un référentiel visuel avant de corriger un mouvement volontaire en cours d’exécution.Research on multisensory integration for goal-directed movements has focused on targets external to the body. In this dissertation, three experiments were conducted to examine sensorimotor transformation processes for movements to body positions (i.e., somatosensory targets). The goal of the first experiment was to investigate if the modality of the cue used to indicate the location of a somatosensory target affects the body representation used to encode the target’s position during movement planning. The results showed that auditory cues prompted the use of an exteroceptive body representation for the encoding of movements to somatosensory targets in visual coordinates. The goal of the second experiment was expand on this finding and examine the neural processes associated with the visual remapping auditory-cued somatosensory targets. It was found that the sensorimotor transformation processes responsible for the conversion of somatosensory target positions to visual coordinates engages visuomotor cortical networks to a greater extent than movements to external visual targets. The goal of the third experiment was to examine the sensorimotor transformation processes employed for the online control of movements to somatosensory targets. These results provide evidence that the remapping of somatosensory targets into visual coordinates may not occur prior to online corrections. Altogether the findings of this thesis reveal that sensory cues can facilitate the remapping of somatosensory targets prior to goal directed actions. However, these remapping processes may be too costly to engage in during online control when there is no vision of the reaching limb

Examining the Sensorimotor Integration Processes Prior to and During Movements to Somatosensory Targets

Previous research on multisensory integration for movement planning and control has focused on movements to targets external to the body. In this dissertation, three experiments were conducted to examine the sensorimotor transformation processes underlying goal-directed actions to targets defined by body positions (i.e., somatosensory targets). The goal of the first experiment was to investigate if the modality of the cue used to indicate the location of a somatosensory target affects the body representation used to encode the target’s position during movement planning. The results showed that auditory cues prompted the use of an exteroceptive body representation for the encoding of movements to a somatosensory target in visual coordinates. The goal of the second experiment was to examine the neural processes associated with the visual remapping of an auditory-cued somatosensory target. It was found that the sensorimotor transformation processes responsible for the conversion of a somatosensory target position into visual coordinates engages visuomotor cortical networks to a greater extent than movements to external visual targets. The goal of the third experiment was to examine the sensorimotor transformation processes employed for the online control of movements to a somatosensory target. The results of this experiment revealed that the remapping of a somatosensory target into visual coordinates may not occur prior to online corrections. Altogether the findings of this thesis reveal that sensory cues can facilitate the remapping of a somatosensory target prior to goal-directed actions. However, these remapping processes may be too costly for use during online control when there is no vision of the reaching limb.Ph.D