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Background: The regulation of gait is critical to many activities of everyday life. When walking, somatosensory information obtained from mechanoreceptors throughout body is delivered to numerous supraspinal networks and used to execute the appropriate motion to meet ever-changing environmental and task demands. Aging and age-related conditions oftentimes alter the supraspinal sensorimotor control of walking, including the responsiveness of the cortical brain regions to the sensorimotor inputs obtained from the peripheral nervous system, resulting in diminished mobility in the older adult population. It is thus important to explicitly characterize such supraspinal sensorimotor elements of walking, providing knowledge informing novel rehabilitative targets. The past efforts majorly relied upon mental imagery or virtual reality to study the supraspinal control of walking. Recent efforts have been made to develop magnetic resonance imaging (MRI)-compatible devices simulating specific somatosensory and/or motor aspects of walking. However, there exists large variance in the design and functionality of these devices, and as such inconsistent functional MRI (fMRI) observations. Methods: We have therefore completed a systematic review to summarize current achievements in the development of these MRI-compatible devices and synthesize available imaging results emanating from studies that have utilized these devices. Results: The device design, study protocol and neuroimaging observations of 26 studies using 13 types of devices were extracted. Three of these devices can provide somatosensory stimuli, eight motor stimuli, and two both types of stimuli. Our review demonstrated that using these devices, fMRI data of brain activation can be successfully obtained when participants remain motionless and experience sensorimotor stimulation during fMRI acquisition. The activation in multiple cortical (e.g., primary sensorimotor cortex) and subcortical (e.g., cerebellum) regions has been each linked to these types of walking-related sensorimotor stimuli. Conclusion: The observations of these publications suggest the promise of implementing these devices to characterize the supraspinal sensorimotor control of walking. Still, the evidence level of these neuroimaging observations was still low due to small sample size and varied study protocols, which thus needs to be confirmed via studies with more rigorous design. [ABSTRACT FROM AUTHOR]

We develop robust methods that allow the specification, control, and transition of a multi-legged robot’s stepping pattern, its ‘gait’, during active locomotion over natural terrain. Resulting gaits emerge through the introduction of controllers that impose appropriately placed repellors within the space of gaits, the torus of relative leg phases, thereby mitigating against dangerous patterns of leg timing. Moreover, these repellors are organized with respect to a natural cellular decomposition of gait space and result in limit cycles with associated basins that are well characterized by these cells, thus conferring a symbolic character upon the overall behavioral repertoire. These ideas are particularly applicable to four- and six-legged robots, for which a large variety of interesting and useful (and, in many cases, familiar) gaits exist, and whose tradeoffs between speed and reliability motivate the desire for transitioning between them during active locomotion. We provide an empirical instance of this gait regulation scheme by application to a climbing hexapod, whose ‘physical layer’ sensor-feedback control requires adequate grasp of a climbing surface but whose closed-loop control perturbs the robot from its desired gait. We document how the regulation scheme secures the desired gait and permits operator selection of different gaits as required during active climbing on challenging surfaces. [ABSTRACT FROM PUBLISHER]

Understanding how individuals navigate challenging accuracy demands required to register a legal jump is important in furthering knowledge of competitive long jumping. Identification of co-ordination tendencies unique to each individual emphasises the need to examine the presence of unique movement solutions and presents important information for individualisation of training environments. In this study, key measures of gait were recorded during the long jump run-ups of 8 athletes at 8 national level competitions in the 2015 and 2016 Australian track and field seasons. These gait measures were examined to identify whether different visual regulation strategies emerged for legal and foul jumps for each competitor. Emergence of different footfall variability data curves, illustrating how step adjustments were distributed across the run-up for each athlete, suggests that athletes interacted differently with features of the competition environment. This observation highlights the importance of movement adaptability as constraints change and emerge across each performance trial. Results provided further support in conceptualising the run-up as a continuous interceptive action task consisting of a series of interconnected events (i.e., individual step lengths) influencing the regulation of gait towards the take-off board. This information can be used by coaches and practitioners in designing training environments that promote athlete adaptation of more functional movement solutions closely matched to the dynamics of competition environments. Results suggest that training designs that help athletes to search, explore and exploit key sources of information from the competition environment will enhance the fit between the individual and the environment and the development of rich, adaptable movement solutions for competitive performance. [ABSTRACT FROM AUTHOR]