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The research aims to: build and record a measure of cognitive participation among second-year female students at the College of Physical Education and Sports Sciences, University of Baghdad. The researchers used the descriptive approach in the survey style for the research sample. The sample was selected from female students and divided into: (10) female students for the survey sample, and (80) female students for the construction and codification sample. The data were statistically analyzed by the researchers using SPSS, the T-test for independent and correlated samples, Pearson's simple correlation coefficient, Cronbach's alpha, Chi-square, and Spearman-Brown. They were recruited for the samples. The study concluded that constructing a measure of cognitive participation for students in the second stage could be applied through the ease and difficulty of its expressions that are appropriate to the research sample, as well as the grades and levels that were reached, which showed that the sample fell within the rating (good and acceptable), and on the other hand the sample was characterized by participation. Cognitive through the results of the scale and its four axes. In conclusion, cognitive participation plays a positive role in performing the ball movement sequence in rhythmic gymnastics.

Consolidation has been associated with performance gains without additional practice (i.e., off-line learning). However, the movement characteristics improving off-line remain poorly understood. To investigate this question, participants were trained to produce a sequence of planar reaching movements toward four different visual targets. The training session with feedback required them to learn the relative time of the movements, the total movement time and aim accurately at each target. The retention test was performed either 10-min or 24-h after. Results revealed that a 24-h consolidation interval did not result in better temporal or spatial accuracy. This finding suggests that off-line learning may be restricted to sequence production tasks in which the different segments must be regrouped ("chunked") together to accelerate their execution. [ABSTRACT FROM AUTHOR]

This paper proposes an efficient origin-estimation bandwidth (OD band) model, which provides dedicated progression bands for arterial traffic based on the real-time dynamic matrix of their estimated OD pairs. The innovations of the OD band model are as follows: First, the dynamics of through and turning-in/out traffics are analyzed based on the matrix of their estimated OD pairs, and used to generate the traffic movement sequence at continuous intersections; Second, the end-time of green interval for lag-lag phase sequence at continuous intersections is determined according to the relevant constraints, the relationship between the start/end-time of green interval and the minimum/maximum green intervals; Third, the bandwidths of the two directions of the artery ware produced, after being weighted by their traffic demands. The intuitiveness, convenience, and feasibility of the OD band model were fully demonstrated through a case study. Overall, the OD band model helps to produce bi-directional progression bands for traffic with many turning movements on the artery, and enables the through and turning-in/out traffics to proceed through continuous intersections, when the signals at those intersections are green. [ABSTRACT FROM AUTHOR]

This study aimed to present a model of post-scratching locomotion with two intermixed central pattern generator (CPG) networks, one for scratching and another for locomotion. We hypothesized that the rhythm generator layers for each CPG are different, with the condition that both CPGs share their supraspinal circuits and their motor outputs at the level of their pattern formation networks. We show that the model reproduces the post-scratching locomotion latency of 6.2 ± 3.5 s, and the mean cycle durations for scratching and post-scratching locomotion of 0.3 ± 0.09 s and 1.7 ± 0.6 s, respectively, which were observed in a previous experimental study. Our findings show how the transition of two rhythmic movements could be mediated by information exchanged between their CPG circuits through routes converging in a common pattern formation layer. This integrated organization may provide flexible and effective connectivity despite the rigidity of the anatomical connections in the spinal cord circuitry.

There is growing experimental evidence that the engagement of different brain areas in a given motor task may change with practice, although the specific brain activity patterns underlying different stages of learning, as defined by kinematic or dynamic performance indices, are not well understood. Here we studied the change in activation in motor areas during practice on sequences of handwriting-like trajectories, connecting four target points on a digitizing table 'as rapidly and as accurately as possible' while lying inside an fMRI scanner. Analysis of the subjects' pooled kinematic and imaging data, acquired at the beginning, middle and end of the training period, revealed no correlation between the amount of activation in the contralateral M1, PM (dorsal and ventral), SMA, preSMA and PPC and the amount of practice per-se. Single trial analysis has revealed that the correlation between the amount of activation in the contralateral M1 and trial mean velocity was partially modulated by performance gains related effects, such as increased hand motion smoothness. Furthermore, it was found that the amount of activation in the contralateral preSMA increased when subjects shifted from generating straight point-to-point trajectories to their spatiotemporal concatenation into a smooth, curved trajectory. Altogether, our results indicate that the amount of activation in the contralateral M1, PMd and preSMA during the learning of movement sequences is correlated with performance gains and that high level motion features (e.g., motion smoothness) may modulate, or even mask correlations between activity changes and low-level motion attributes (e.g., trial mean velocity).

Transfer (i.e., the application of a learned skill in a novel context) is an important and desirable outcome of motor skill learning. While much research has been devoted to understanding transfer of explicit skills the mechanisms of skill transfer after incidental learning remain poorly understood. The aim of this study was to (1) examine the effect of practice schedule on transfer and (2) investigate whether sequence-specific knowledge can transfer to an unfamiliar sequence context. We trained two groups of participants on an implicit serial response time task under a Constant (one sequence for 10 blocks) or Variable (alternating between two sequences for a total of 10 blocks) practice schedule. We evaluated response times for three types of transfer: task-general transfer to a structurally non-overlapping sequence, inter-manual transfer to a perceptually identical sequence, and sequence-specific transfer to a partially overlapping (three shared triplets) sequence. Results showed partial skill transfer to all three sequences and an advantage of Variable practice only for task-general transfer. Further, we found expression of sequence-specific knowledge for familiar sub-sequences in the overlapping sequence. These findings suggest that (1) constant practice may create interference for task-general transfer and (2) sequence-specific knowledge can transfer to a new sequential context. [ABSTRACT FROM AUTHOR]

An experiment that utilized a 16-element movement sequence was designed to determine the impact of eye movements on sequence learning. The participants were randomly assigned to two experimental groups: a group that was permitted to use eye movements (FREE) and a second group (FIX) that was instructed to fixate on a marker during acquisition (ACQ). A retention test (RET) was designed to provide a measure of learning, and two transfer tests were designed to determine the extent to which eye movements influenced sequence learning. The results demonstrated that both groups decreased the response time to produce the sequence, but the participants in the FREE group performed the sequence more quickly than participants of the FIX group during the ACQ, RET and the two transfer tests. Furthermore, continuous visual control of response execution was reduced over the course of learning. The results of the transfer tests indicated that oculomotor information regarding the sequence can be stored in memory and enhances response production. [ABSTRACT FROM AUTHOR]

Background Medical doctors are essential for the German public and occupational health system. They ensure the productivity of German society by enabling people to regain and recover their health. That is why the physicians' health and hence their productivity require special attention. Musculoskeletal disorders have a high prevalence in this work area. As a consequence, movement sequences, range of motions, and body postures of physicians in the course of the working day are in focus of this research project. Methods For this investigation 21 male or female junior physicians of various conservative medical disciplines will be covered. Data will be collected over one working day (approx. 9 hours). The CUELA system attached to the test person's body detects body posture and/or movements. This biomechanical measurement system ensures a locomotor and posture analysis that includes movement sequences, movement intensity, and range of motions to qualify the work tasks. For data analysis intra- and inter-professional comparisons are chosen. Conclusions Working movement sequence analysis of physicians by means of the CUELA system is exclusive and novel in its focus. Up to now, knowledge of the working tasks of medical doctors has only been acquired by real-time observation approaches to work activity. In addition to this method of analysis, the CUELA system is able to record quantified biomechanical data about musculoskeletal loads of ordinary working tasks. Workloads and activities of physicians can be improved by ergonomic work design to reduce musculoskeletal disorders by utilizing the data collected. The healthcare system in Germany will thus be optimized by improving medical doctors' health. Consequently, MAGRO-MSA will also be used for other healthcare professions such as nurses and physicians assistants. [ABSTRACT FROM AUTHOR]

A new method of lower-limb exoskeleton control aimed at improving the agility of leg-swing motion is presented. In the absence of control, an exoskeleton's mechanism usually hinders agility by adding mechanical impedance to the legs. The uncompensated inertia of the exoskeleton will reduce the natural frequency of leg swing, probably leading to lower step frequency during walking as well as increased metabolic energy consumption. The proposed controller emulates inertia compensation by adding a feedback loop consisting of low-pass filtered angular acceleration multiplied by a negative gain. This gain simulates negative inertia in the low-frequency range. The resulting controller combines two assistive effects: increasing the natural frequency of the lower limbs and performing net work per swing cycle. The controller was tested on a statically mounted exoskeleton that assists knee flexion and extension. Subjects performed movement sequences, first unassisted and then using the exoskeleton, in the context of a computer-based task resembling a race. In the exoskeleton's baseline state, the frequency of leg swing and the mean angular velocity were consistently reduced. The addition of inertia compensation enabled subjects to recover their normal frequency and increase their selected angular velocity. The work performed by the exoskeleton was evidenced by catch trials in the protocol. [ABSTRACT FROM AUTHOR]

Abstract: Motor timing is essential for performing self-initiated movement sequences. Here, we investigated how sequence rhythm, or the timing for co-ordinating movements within a sequence, contributes to action preparation, compared with other processes occurring during sequence planning. First, we recorded the readiness potential (RP) in a condition of complex sequence rhythm and in condition of high demand on the timing for sequence initiation. We found that sequence rhythm and sequence initiation are independent processes, with sequence initiation contributing to early RP. Second, we compared the RP recorded in a condition of complex sequence rhythm and in a condition of complex sequence order, in which a complex combination of finger sub-movements had to be correctly ordered within a sequence. We found that sequence rhythm and sequence order share common processes occurring late RP. We suggest that the preparation for movement involves independent processes devoted to different aspects of motor timing and sequencing. [Copyright &y& Elsevier]

Abstract: A key problem in reinforcement learning is how an animal is able to learn a sequence of movements when the reward signal only occurs at the end of the sequence. We describe how a hierarchical dynamical model of motor function is able to solve the problem of delayed reward in learning movement sequences using associative (Hebbian) learning. At the lowest level, the motor system encodes simple movements or primitives, while at higher levels the system encodes sequences of primitives. During training, the network is able to learn a high level motor program composed of a specific temporal sequence of motor primitives. The network is able to achieve this despite the fact that the reward signal, which indicates whether or not the desired motor program has been performed correctly, is received only at the end of each trial during learning. Use of a continuous attractor network in the architecture enables the network to generate the motor outputs required to produce the continuous movements necessary to implement the motor sequence. [Copyright &y& Elsevier]

Abstract: Objective: To estimate the processing time and neuromuscular delay required to extract and process sensory information from the ankle in order to coordinate an upper extremity movement sequence. Methods: Nineteen able-bodied subjects were tested on their ability to perform a motor task that involved extension of their left index finger when their left ankle was passively plantar flexed at random velocities through a predetermined target angle. Results: We found that the able-bodied subjects were able to adjust their finger responses up to ankle velocities of 70°/s (300ms). Reaction time, defined as the delay between onset of ankle rotation and how quickly the index finger could be extended, was 215ms. The processing time and conduction delay was estimated to be ∼85ms. Conclusions: These results indicate that the nervous system processes kinesthetic input related to joint rotation of the ankle with the central mechanisms to execute a planned coordinated task with the upper extremity. Significance: The time required to process proprioceptive information from the leg to perform a coordinated task with the upper extremity may vary throughout the lifespan. Understanding the effects of age, exercise, or injury on proprioceptive processing time may have important clinical implications. [Copyright &y& Elsevier]

We used functional magnetic resonance imaging to investigate if different brain regions are controlling the temporal and ordinal structure of movement sequences during performance. Human subjects performed overlearned spatiotemporal sequences of key- presses using the right index finger Under different conditions, the temporal and the ordinal structure of the sequences were varied systematically in relation to each other, using a factorial design: COMBINED had a rhythm of eight temporal intervals and a serial order of eight keys; TEMPORAL had an eight-interval rhythm produced on one key; ORDINAL had an isochronous rhythm and an eight-key serial order; two control conditions had an isochronous pulse performed on one or two keys, respectively. Brain regions involved in rhythmic and ordinal control of the sequences were revealed by analysing main effect contrasts for the corresponding factors. TEMPORAL and ORDINAL were also compared directly to test for significant differences. A dissociation was found between largely the presupplementary motor area, the right inferior frontal gyrus and precentral sulcus, and the bilateral superior temporal gyri, involved in temporal control, and lateral fronto-parietal areas, the basal ganglia and the cerebellum, which were implicated in ordinal control. The vermis and the superior colliculus were the only regions with an activity increase specifically related to combining long temporal and ordinal sequences. We conclude that humans use different brain networks for temporal and ordinal sequence control, and that the performance of combined sequences activates both networks, the medial cerebellum, and the superior colliculus. [ABSTRACT FROM AUTHOR]

Embedded in neural and behavioral organization is a structure of sensorimotor space. Both this embedded spatial structure and the structure of physical space inform sensorimotor control. This paper reviews studies in which the gravitational vertical and horizontal are crucial. The mathematical expressions of spatial geometry in these studies indicate methods for investigating sensorimotor control in freefall. In freefall, the spatial structure introduced by gravitation – the distinction between vertical and horizontal – does not exist. However, an astronaut arriving in space carries the physiologically-embedded distinction between horizontal and vertical learned on earth. The physiological organization based on this distinction collapses when the strong otolith activity and other gravitational cues for sensorimotor behavior become unavailable. The mathematical methods in this review are applicable in understanding the changes in physiological organization as an astronaut adapts to sensorimotor control in freefall. Many mathematical languages are available for characterizing the logical structures in physiological organization. Here, group theory is used to characterize basic structure of physical and physiological spaces. Dynamics and topology allow the grouping of trajectory ranges according to the outcomes or attractors. The mathematics of ordered structures express complex orderings, such as in multiphase movements in which different parts of the body are moving in different phase sequences. Conditional dynamics, which combines dynamics with the mathematics of ordered structures, accommodates the parsing of movement sequences into trajectories and transitions. Studies reviewed include those of the sit-to-stand movement and early locomotion, because of the salience of gravitation in those behaviors. Sensorimotor transitions and the conditions leading to them are characterized in conditional dynamic control structures that do not require thinking of an organism as an input-output device. Conditions leading to sensorimotor transitions on earth assume the presence of a gravitational vertical which is lacking in space. Thus, conditions used on earth for sensorimotor transitions may become ambiguous in space. A platform study in which sensorimotor transition conditions are ambiguous and are related to motion sickness is reviewed. [ABSTRACT FROM AUTHOR]

We investigated the modulation of cerebellar activation by predictive and non-predictive sequential finger movements. It is hypothesized that the prediction of desired movement sequences and adaptation to new movement parameters is mediated by the cerebellum. Using functional MRI at 1.5 T, seven normal subjects performed sequential finger to thumb opposition movements, either in predictive (repeatedly 2,3,4,5) or non-predictive (randomized) fashion at a constant frequency of 1 Hz. Performance and error rates were monitored by simultaneous recording of the finger movements. Predictive sequential finger opposition movements activated a cerebellar network including the lobuli IV-VI ipsilateral to the movements, the contralateral lobuli IV-VI, the vermis, and lobuli VIIB-VIII ipsilaterally. Non-predictive compared to predictive finger opposition movements activated a broader area within the ipsi- and contralateral anterior cerebellum, lobuli IV-VI, the vermis, and the ipsilateral lobuli VIIB-VIII. Additional activation foci were found in the contralateral lobuli VIIA and VIIB-VIII. Our study demonstrates a modulated information processing within the cerebellar network dependent on the predictability of movement sequences. [ABSTRACT FROM AUTHOR]

Simple Summary: Post-scratching locomotion in cats refers to the spontaneous occurrence of an episode of locomotion generated after an event of scratching. This phenomenon suggests the potential existence of shared neurons in the spinal cord mediating the transition from one rhythmic motor task to another. Here, we examine this possibility with a mathematical model, reproducing the experimental observations. Our findings reveal a possible mechanism in which the central nervous system could share neuronal circuits from two central pattern generators to produce a sequence of different rhythmic motor actions. This study aimed to present a model of post-scratching locomotion with two intermixed central pattern generator (CPG) networks, one for scratching and another for locomotion. We hypothesized that the rhythm generator layers for each CPG are different, with the condition that both CPGs share their supraspinal circuits and their motor outputs at the level of their pattern formation networks. We show that the model reproduces the post-scratching locomotion latency of 6.2 ± 3.5 s, and the mean cycle durations for scratching and post-scratching locomotion of 0.3 ± 0.09 s and 1.7 ± 0.6 s, respectively, which were observed in a previous experimental study. Our findings show how the transition of two rhythmic movements could be mediated by information exchanged between their CPG circuits through routes converging in a common pattern formation layer. This integrated organization may provide flexible and effective connectivity despite the rigidity of the anatomical connections in the spinal cord circuitry. [ABSTRACT FROM AUTHOR]

Both motor and cognitive aspects of behavior depend on dynamic, accurately timed neural processes in large-scale brain networks. Here, we studied synchronous interplay between cortical regions during production of cognitive-motor sequences in humans. Specifically, variants of handwriting that differed in motor variability, linguistic content, and memorization of movement cues were contrasted to unveil functional sensitivity of corticocortical connections. Data-driven magnetoencephalography mapping (n = 10) uncovered modulation of mostly left-hemispheric corticocortical interactions, as quantified by relative changes in phase synchronization. At low frequencies (~2-13 Hz), enhanced frontoparietal synchrony was related to regular handwriting, whereas premotor cortical regions synchronized for simple loop production and temporo-occipital areas for a writing task substituting normal script with loop patterns. At the beta-to-gamma band (~13-45 Hz), enhanced synchrony was observed for regular handwriting in the central and frontoparietal regions, including connections between the sensorimotor and supplementary motor cortices and between the parietal and dorsal premotor/precentral cortices. Interpreted within a modular framework, these modulations of synchrony mainly highlighted interactions of the putative pericentral subsystem of hand coordination and the frontoparietal subsystem mediating working memory operations. As part of cortical dynamics, interregional phase synchrony varies depending on task demands in production of cognitive-motor sequences., (© The Author(s) 2019. Published by Oxford University Press.)