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Biohybrid robots have been developed for biomedical applications and industrial robotics. However, the biohybrid robots have limitations to be applied in neurodegenerative disease research due to the absence of a central nervous system. In addition, the organoids‐on‐a‐chip has not yet been able to replicate the physiological function of muscle movement in the human motor system, which is essential for evaluating the accuracy of the drugs used for treating neurodegenerative diseases. Here, a human motor system‐based biohybrid robot‐on‐a‐chip composed of a brain organoid, multi‐motor neuron spheroids, and muscle bundle on solid substrateis proposed to evaluate the drug effect on neurodegenerative diseases for the first time. The electrophysiological signals from the cerebral organoid induced the muscle bundle movement through motor neuron spheroids. To evaluate the drug effect on Parkinson's disease (PD), a patient‐derived midbrain organoid is generated and incorporated into a biohybrid robot‐on‐a‐chip. The drug effect on PD is successfully evaluated by measuring muscle bundle movement. The muscle bundle movement of PD patient‐derived midbrain organoid‐based biohybrid robot‐on‐a‐chip is increased from 4.5 ± 0.99 µm to 18.67 ± 2.25 µm in response to levodopa. The proposed human motor system‐based biohybrid robot‐on‐a‐chip can serve as a standard biohybrid robot model for drug evaluation. [ABSTRACT FROM AUTHOR]

Abstract Biohybrid robots have been developed for biomedical applications and industrial robotics. However, the biohybrid robots have limitations to be applied in neurodegenerative disease research due to the absence of a central nervous system. In addition, the organoids‐on‐a‐chip has not yet been able to replicate the physiological function of muscle movement in the human motor system, which is essential for evaluating the accuracy of the drugs used for treating neurodegenerative diseases. Here, a human motor system‐based biohybrid robot‐on‐a‐chip composed of a brain organoid, multi‐motor neuron spheroids, and muscle bundle on solid substrateis proposed to evaluate the drug effect on neurodegenerative diseases for the first time. The electrophysiological signals from the cerebral organoid induced the muscle bundle movement through motor neuron spheroids. To evaluate the drug effect on Parkinson's disease (PD), a patient‐derived midbrain organoid is generated and incorporated into a biohybrid robot‐on‐a‐chip. The drug effect on PD is successfully evaluated by measuring muscle bundle movement. The muscle bundle movement of PD patient‐derived midbrain organoid‐based biohybrid robot‐on‐a‐chip is increased from 4.5 ± 0.99 µm to 18.67 ± 2.25 µm in response to levodopa. The proposed human motor system‐based biohybrid robot‐on‐a‐chip can serve as a standard biohybrid robot model for drug evaluation.

The electroencephalographically measured Bereitschafts (readiness)-potential in the supplementary motor area (SMA) serves as a signature of the preparation of motor activity. Using a multichannel, noninvasive near-infrared spectroscopy (NIRS) imager, we studied the vascular correlate of the readiness potential. Sixteen healthy subjects performed a self-paced or externally triggered motor task in a single or repetitive pattern, while NIRS simultaneously recorded the task-related responses of deoxygenated hemoglobin (HbR) in the primary motor area (M1) and the SMA. Right-hand movements in the repetitive sequence trial elicited a significantly greater HbR response in both the SMA and the left M1 compared to left-hand movements. During the single sequence condition, the HbR response in the SMA, but not in the M1, was significantly greater for self-paced than for externally cued movements. Nonetheless, an unequivocal temporal delay was not found between the SMA and M1. Near-infrared spectroscopy is a promising, noninvasive bedside tool for the neuromonitoring of epileptic seizures or cortical spreading depolarizations (CSDs) in patients with epilepsy, stroke, or brain trauma because these pathological events are associated with typical spatial and temporal changes in HbR. Propagation is a characteristic feature of these events which importantly supports their identification and characterization in invasive recordings. Unfortunately, the present noninvasive study failed to show a temporal delay during self-paced movements between the SMA and M1 as a vascular correlate of the readiness potential. Although this result does not exclude, in principle, the possibility that scalp-NIRS can detect a temporal delay between different regions during epileptic seizures or CSDs, it strongly suggests that further technological development of NIRS should focus on both improved spatial and temporal resolution. This article is part of a Special Issue entitled Status Epilepticus. [ABSTRACT FROM AUTHOR]

Abstract: People generally have a strong and immediate intuition whether they are the author of an action or not. Nevertheless, recent psychological studies focused on situations of ambiguous agency. These studies concluded that agency is an inference rather than a direct perception, and is, at least sometimes, illusory. Moreover, shared representations of executed and merely observed actions within the sensorimotor system pose a challenge to the idea that a sense of agency can be grounded within that system. Here, we sought to investigate whether the human motor system is indeed sensitive to whether observed actions are linked to agency or not. In addition, we investigated whether the mere observation of an action has comparable effects on low-level, sensorimotor measures of agency, and on high-level, explicit representations of agency. To this end, we instructed participants to make simple manual movements, and manipulated the temporal correspondence between the movement that they made and the movement that they observed. Motor-evoked potentials to single-pulse TMS were taken as a low-level, sensorimotor measure of agency. To assess explicit representations of agency, participants verbally judged whether or not the observed movement temporally corresponded to the movement they executed. The results showed that corticospinal excitability varied with the degree of temporal correspondence of the executed and observed movements. Moreover, explicit agency judgments could be predicted from corticospinal excitability. This suggests that explicit judgments of agency could be directly based on information within the sensorimotor system. [Copyright &y& Elsevier]

Cognitive load theory is intended to provide instructional strategies derived from experimental, cognitive load effects. Each effect is based on our knowledge of human cognitive architecture, primarily the limited capacity and duration of a human working memory. These limitations are ameliorated by changes in long-term memory associated with learning. Initially, cognitive load theory's view of human cognitive architecture was assumed to apply to all categories of information. Based on Geary's ( Educational Psychologist 43, 179-195 ; ) evolutionary account of educational psychology, this interpretation of human cognitive architecture requires amendment. Working memory limitations may be critical only when acquiring novel information based on culturally important knowledge that we have not specifically evolved to acquire. Cultural knowledge is known as biologically secondary information. Working memory limitations may have reduced significance when acquiring novel information that the human brain specifically has evolved to process, known as biologically primary information. If biologically primary information is less affected by working memory limitations than biologically secondary information, it may be advantageous to use primary information to assist in the acquisition of secondary information. In this article, we suggest that several cognitive load effects rely on biologically primary knowledge being used to facilitate the acquisition of biologically secondary knowledge. We indicate how incorporating an evolutionary view of human cognitive architecture can provide cognitive load researchers with novel perspectives of their findings and discuss some of the practical implications of this view. [ABSTRACT FROM AUTHOR]

Abstract: Evidence from studies in both animals and humans suggests that pharmacological stimulation of the noradrenergic system may modulate cortical excitability. However, the influence of such a modulation on the motor system remains unclear. We here explored the effects of noradrenergic stimulation on different motor tasks with increasing complexity and sensorimotor demands. Healthy human subjects received either reboxetine – a selective noradrenaline reuptake inhibitor – or placebo in a double-blind within-subject design. The analysis of movement kinematics revealed differential effects of RBX on subjects’ motor performance. While isolated stereotypic finger movements and simple reach-to-grasp movements did not change under RBX stimulation (compared to placebo), subjects showed a significant gain in movement speed in visuomotor tasks requiring online-control of precision movements. The results suggest that stimulating the noradrenergic system via RBX does not influence motor performance in general, but rather supports neural circuits involved in visuomotor control of movements. [Copyright &y& Elsevier]

Computer modeling and control of the human motor system might be helpful for understanding the mechanism of human motor system and for the diagnosis and treatment of neuromuscular disorders. In this paper, a brief view of the equilibrium point hypothesis for human motor system modeling is given, and the λ-model derived from this hypothesis is studied. The stability of the λ-model based on equilibrium and Jacobian matrix is investigated. The results obtained in this paper suggest that the λ-model is stable and has a unique equilibrium point under certain conditions. [ABSTRACT FROM AUTHOR]

Abstract: Systematic clinical observations of patients'' characteristics, health status and outcomes generate meaningful scientific data for descriptive research. This article presents a concept and a method available to the practitioner for the purpose of conducting office-based descriptive research of palpable neuro-musculo-skeletal dysfunction (nmsk). Functional expansion of the traditional osteopathic structural concept of segmental dysfunction has generated much needed evidence-based data for objective signs of problems in the human motor system. To create positive directions for increasing experimental research development, the authors make use of vertebral segmental responses to identified functional motion tests. Their method includes: (1) establishing criteria for assessment of individual vertebral 3-dimensional motor behaviour, (2) assessing responses from a fundamental 3-segment unit of nmsk dysfunction, and (3) generating objective signs of change in clinical data about dysfunction for reporting outcomes of osteopathic manipulative procedures. [Copyright &y& Elsevier]

In monkeys, motor outputs from premotor cortex (PM) involve cortico-cortical connections with primary motor cortex (M1). However, in humans, the functional organization of PM and its relationship with the corticospinal tract (CST) is still uncertain. This study was carried out in 21 patients undergoing intraoperative brain mapping prior to tumor resection. The left ventrolateral premotor cortex (vlPM-BA6) was identified preoperatively by functional magnetic resonance imaging, and then investigated intraoperatively using high frequency direct electrical stimulation (HF-DES) of the convexity of M1 and vlPM-BA6, with simultaneous recording of motor-evoked potentials (MEPs) from oro-facial, hand and arm muscles. The somatotopy, organization of evoked responses, latency of MEPs, and cortical excitability of vlPM-BA6 were compared with reference data from M1. vlPM-BA6 was found to be less excitable, with significantly longer MEP latencies than M1. In addition to the pure oro-facial and hand-arm muscle representation, a "transition oro-hand zone" was identified in vlPM-BA6. The longer latency of vlPM-BA6 MEPs suggests that human vlPM could act on spinal motoneurons either directly through more slowly conducting CST fibers or via less direct pathways through M1, brainstem, or spinal mechanisms. The results help in disclosing the very different roles of vlPM and M1 in motor control., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)