Control Mechanisms in Oscillatory Motor Behavior

Human Motor ◽

Inertial Loading

Studies on unimpaired humans have demonstrated that the central nervous system employs internal representations of limb dynamics and intended movement trajectories for planning muscle activation during pointing and reaching tasks. However, when performing rhythmic movements, it has been hypothesized that a control scheme employing an autonomous oscillator — a simple feedback circuit lacking exogenous input — can maintain stable control. Here we investigate whether such simple control architectures that can realize rhythmic movement that we observe in experimental data. We asked subjects to perform rhythmic movements of the forearm while a robotic interface simulated inertial loading. Our protocol included unexpected increases in loading (catch trials) as a probe to reveal any systematic changes in frequency and amplitude. Our primary findings were that increased inertial loading resulted in reduced frequency of oscillations, and in some cases multiple frequencies. These results exhibit some agreement with an autonomous oscillator model, though other features are more consistent with feedforward planning of force. This investigation provides a theoretical and experimental framework to reveal basic computational elements for how the human motor system achieves skilled rhythmic movement.

Modeling Qualitative Changes in Bimanual Movements

International Journal of Bifurcation and Chaos ◽

10.1142/s0218127497001163 ◽

1997 ◽

Vol 07 (06) ◽

pp. 1441-1450 ◽

Cited By ~ 5

Author(s):

C. Scheffczyk ◽

A. Zaikin ◽

M. Rosenblum ◽

R. Engbert ◽

R. Krampe ◽

...

Keyword(s):

Correction Function ◽

Coupling Mechanism ◽

Control Mechanisms ◽

Rhythmic Movements ◽

Bimanual Movements ◽

Iterated Maps ◽

Essential Properties ◽

Level Of Training ◽

Qualitative Changes

In the cognitive sciences the study of complex rhythmic movements is a challenging problem which is a subject of extensive research. Experiments on bimanual movements are paradigms for studying the ability of humans on timing and coordination. Such experiments give insights into the control mechanisms of the central nervous system and also reflect the functional state and level of training of the person tested. In a recent study on bimanual polyrhythm production the existence of phase transitions in dependence on the speed of performance has been shown. In this paper we present an iterated map model to explain main findings of these experiments. The model consists of two iterated maps describing the dynamics of the finger movements. The essential properties of the model are a nonlinear correction function and a coupling mechanism between the two maps. Numerical simulations show that the model is in qualitative agreement with the experimentally observed phenomena.

Limits in motor control bandwidth during stick balancing

Journal of Neurophysiology ◽

10.1152/jn.00429.2012 ◽

2013 ◽

Vol 109 (10) ◽

pp. 2523-2527 ◽

Cited By ~ 8

Author(s):

N. Peter Reeves ◽

Pramod Pathak ◽

John M. Popovich ◽

Vilok Vijayanagar

Keyword(s):

Motor Control ◽

Natural Frequency ◽

Muscle Activation ◽

Threshold Effect ◽

Trunk Muscles ◽

Human Control ◽

Agonist And Antagonist ◽

Human Motor ◽

Electromyographic Signals

Why can we balance a yardstick but not a pencil on the tip of our finger? As with other physical systems, human motor control has constraints, referred to as bandwidth, which restricts the range of frequency over which the system can operate within some tolerated level of error. To investigate control bandwidth, the natural frequency of a stick used during a stick-balancing task was modified by adjusting the height of a mass attached to the stick. The ability to successfully balance the stick with the mass positioned at four different heights was determined. In addition, electromyographic signals from forearm and trunk muscles were recorded during the trials. We hypothesized that 1) the probability of successfully balancing would decrease as mass height decreased; and 2) the level of muscle activation in both agonist and antagonist would increase as the natural frequency of the stick increased. Results showed that as the mass height decreased the probability of successfully balancing the stick decreased. Changes in the probability of success with respect to mass height showed a threshold effect, suggesting that limits in human control bandwidth were approached at the lowest mass height. Also, the level of muscle activation in both the agonist and antagonist of the forearm and trunk increased linearly as the natural frequency of the stick increased. These changes in muscle activation suggest that the central nervous system adapts muscle activation to task dynamics, possibly to improve control bandwidth.

Perspectives in Human Motor Behavior

Contemporary Psychology ◽

10.1037/021653 ◽

1983 ◽

Vol 28 (10) ◽

pp. 785-786

Author(s):

Beth Kerr

Keyword(s):

Motor Behavior ◽

Human Motor

Muscle activation patterns are more constrained and regular in treadmill than in overground human locomotion

10.1101/2020.07.07.191080 ◽

2020 ◽

Author(s):

Ilaria Mileti ◽

Aurora Serra ◽

Nerses Wolf ◽

Victor Munoz-Martel ◽

Antonis Ekizos ◽

...

Keyword(s):

Neural Control ◽

Muscle Activation ◽

Human Locomotion ◽

Activation Patterns ◽

Motor Primitives ◽

Muscle Activation Patterns ◽

Synergistic Activation ◽

Clinical Environments ◽

Main Activity

AbstractThe use of motorized treadmills as convenient tools for the study of locomotion has been in vogue for many decades. However, despite the widespread presence of these devices in many scientific and clinical environments, a full consensus on their validity to faithfully substitute free overground locomotion is still missing. Specifically, little information is available on whether and how the neural control of movement is affected when humans walk and run on a treadmill as compared to overground. Here, we made use of linear and nonlinear analysis tools to extract information from electromyographic recordings during walking and running overground, and on an instrumented treadmill. We extracted synergistic activation patterns from the muscles of the lower limb via non-negative matrix factorization. We then investigated how the motor modules (or time-invariant muscle weightings) were used in the two locomotion environments. Subsequently, we examined the timing of motor primitives (or time-dependent coefficients of muscle synergies) by calculating their duration, the time of main activation, and their Hurst exponent, a nonlinear metric derived from fractal analysis. We found that motor modules were not influenced by the locomotion environment, while motor primitives resulted overall more regular in treadmill than in overground locomotion, with the main activity of the primitive for propulsion shifted earlier in time. Our results suggest that the spatial and sensory constraints imposed by the treadmill environment forced the central nervous system to adopt a different neural control strategy than that used for free overground locomotion. A data-driven indication that treadmills induce perturbations to the neural control of locomotion.

Vanishing White Matter Disease Expression of Truncated EIF2B5 Activates Induced Stress Response

10.1101/2020.05.05.078295 ◽

2020 ◽

Author(s):

Matthew D. Keefe ◽

Haille E. Soderholm ◽

Hung-Yu Shih ◽

Tamara J. Stevenson ◽

Kathryn A. Glaittli ◽

...

Keyword(s):

White Matter ◽

Motor Behavior ◽

Somatic Growth ◽

Initiation Factor ◽

White Matter Disease ◽

Oligodendrocyte Precursor ◽

Vanishing White Matter Disease ◽

Development And Validation ◽

Vanishing White Matter

AbstractVanishing White Matter disease (VWM) is a severe leukodystrophy of the central nervous system caused by mutations in subunits of the eukaryotic initiation factor 2B complex (eIF2B). Current models only partially recapitulate key disease features, and pathophysiology is poorly understood. Through development and validation of zebrafish (Danio rerio) models of VWM, we demonstrate that zebrafish eif2b mutants phenocopy VWM, including impaired somatic growth, early lethality, impaired myelination, loss of oligodendrocyte precursor cells, increased apoptosis in the CNS, and impaired motor swimming behavior. Expression of human EIF2B2 in the zebrafish eif2b2 mutant rescues lethality and CNS apoptosis, demonstrating conservation of function between zebrafish and human. In the mutants, intron 12 retention leads to expression of a truncated eif2b5 transcript. Expression of the truncated eif2b5 in wild-type larva impairs motor behavior and activates the ISR, suggesting that a feed-forward mechanism in VWM is a significant component of disease pathophysiology.

NIKOLAI ALEKSANDROVICH BERNSTEIN — PIONEER IN CONTROL AND CYBERNETICS

International Journal of Humanoid Robotics ◽

10.1142/s0219843610002040 ◽

2010 ◽

Vol 07 (01) ◽

pp. 213-222 ◽

Author(s):

MIOMIR VUKOBRATOVIĆ ◽

MILOŠ JOVANOVIĆ

Keyword(s):

Motor Behavior ◽

Mathematical Formulation ◽

Voluntary Movements ◽

Vital Activity ◽

Dynamic Regulation ◽

Ocular Accommodation ◽

Pupillary Reaction ◽

Human Movements ◽

Physiological Theory

The article presents the facts about the pioneering research results of Professor Nikolai Bernstein in the area of man's voluntary movements. Relevant data are given concerning the priority of introducing the notion of feedback in the process of active voluntary human movements, twelve years before the known Wiener's publication. Bernstein demonstrated how the problems of general physiology can be explored in terms of the structural analysis of movements. He dealt with the most important aspects of the vital activity of higher organisms, and how this has been accorded the place in physiology and, when it developed, promised to be of the greatest value in cybernetics and in the exact mathematical formulation of a physiological theory of motor behavior. In his research, Bernstein modeled the function of the central nervous system and offered the cyberneticists a system for the development of analogs for experimental model-making that was not only incomparably richer than examples of internal stabilizing processes (blood-pressure, temperature and sugar-level regulating systems, for example), and also more complex than the systems of dynamic regulation that have already been studied in some depth, such as the mechanisms of ocular accommodation, or of the pupillary reaction.

Mechanisms for generating temporal filters in the electrosensory system

Journal of Experimental Biology ◽

10.1242/jeb.202.10.1281 ◽

1999 ◽

Vol 202 (10) ◽

pp. 1281-1289 ◽

Author(s):

G.J. Rose ◽

E.S. Fortune

Keyword(s):

Nervous System ◽

Discharge Rate ◽

Temporal Structure ◽

Sensory Information ◽

Gain Control ◽

Membrane Properties ◽

Control Mechanisms ◽

Temporal Features ◽

Level Of Activity ◽

The Central Nervous System

Temporal patterns of sensory information are important cues in behaviors ranging from spatial analyses to communication. Neural representations of the temporal structure of sensory signals include fluctuations in the discharge rate of neurons over time (peripheral nervous system) and the differential level of activity in neurons tuned to particular temporal features (temporal filters in the central nervous system). This paper presents our current understanding of the mechanisms responsible for the transformations between these representations in electric fish of the genus Eigenmannia. The roles of passive and active membrane properties of neurons, and frequency-dependent gain-control mechanisms are discussed.

RESPIRATORY MANIFESTATIONS IN ENDOCRINE DISEASES

Medicine and Pharmacy Reports ◽

10.15386/cjmed-671 ◽

2016 ◽

Vol 89 (4) ◽

pp. 459-463 ◽

Author(s):

Codruţa Lencu ◽

Teodora Alexescu ◽

Mirela Petrulea ◽

Monica Lencu

Keyword(s):

Sleep Apnea ◽

Central Sleep Apnea ◽

Regulation Of Respiration ◽

Control Mechanisms ◽

Upper Airways ◽

Respiratory Disorders ◽

Medical Practitioners ◽

Endocrine Diseases ◽

Pulmonary Arterial

The control mechanisms of respiration as a vital function are complex: voluntary – cortical, and involuntary – metabolic, neural, emotional and endocrine. Hormones and hypothalamic neuropeptides (that act as neurotrasmitters and neuromodulators in the central nervous system) play a role in the regulation of respiration and in bronchopulmonary morphology. This article presents respiratory manifestations in adult endocrine diseases that evolve with hormone deficit or hypersecretion. In hyperthyroidism, patients develop ventilation disorders, obstructive and central sleep apnea, and pleural collection. The respiratory abnormalities in hyperthyroidism as a result of the hypermetabolic action of thyroid hormones are hyperventilation, myopathy and cardiovascular involvement; recent studies have reported pulmonary arterial hypertension in Graves’ disease, as a result of the association of several mechanisms. Thyroid hypertrophy can induce through compression of the upper airways dyspnea, stridor, wheezing and cough. The respiratory disorders in acromegaly are ventilatory dysfunction and sleep apnea, which contribute to an unfavorable evolution of the disease. Respiratory changes in parathyroid, adrenal and reproductive system diseases have been described. Respiratory disorders should be recognized, investigated and monitored by medical practitioners of various specialties (family physicians, internists, endocrinologists, pneumologists, cardiologists). They are frequently severe, causing an unfavorable evolution of the associated endocrine and respiratory disease.

Complementary spatial and timing control in rhythmic arm movements

Journal of Neurophysiology ◽

10.1152/jn.00194.2018 ◽

2019 ◽

Vol 121 (4) ◽

pp. 1543-1560 ◽

Cited By ~ 3

Author(s):

Robert W. Nickl ◽

M. Mert Ankarali ◽

Noah J. Cowan

Keyword(s):

Visual Feedback ◽

Haptic Feedback ◽

Motor Behavior ◽

Hand Movement ◽

Arm Movements ◽

Timing Synchronization ◽

Sufficient Information ◽

Spatial Accuracy ◽

Rhythmic Movements ◽

Spatial Error

Volitional rhythmic motor behaviors such as limb cycling and locomotion exhibit spatial and timing regularity. Such rhythmic movements are executed in the presence of exogenous visual and nonvisual cues, and previous studies have shown the pivotal role that vision plays in guiding spatial and temporal regulation. However, the influence of nonvisual information conveyed through auditory or touch sensory pathways, and its effect on control, remains poorly understood. To characterize the function of nonvisual feedback in rhythmic arm control, we designed a paddle juggling task in which volunteers bounced a ball off a rigid elastic surface to a target height in virtual reality by moving a physical handle with the right hand. Feedback was delivered at two key phases of movement: visual feedback at ball peaks only and simultaneous audio and haptic feedback at ball-paddle collisions. In contrast to previous work, we limited visual feedback to the minimum required for jugglers to assess spatial accuracy, and we independently perturbed the spatial dimensions and the timing of feedback. By separately perturbing this information, we evoked dissociable effects on spatial accuracy and timing, confirming that juggling, and potentially other rhythmic tasks, involves two complementary processes with distinct dynamics: spatial error correction and feedback timing synchronization. Moreover, we show evidence that audio and haptic feedback provide sufficient information for the brain to control the timing synchronization process by acting as a metronome-like cue that triggers hand movement. NEW & NOTEWORTHY Vision contains rich information for control of rhythmic arm movements; less is known, however, about the role of nonvisual feedback (touch and sound). Using a virtual ball bouncing task allowing independent real-time manipulation of spatial location and timing of cues, we show their dissociable roles in regulating motor behavior. We confirm that visual feedback is used to correct spatial error and provide new evidence that nonvisual event cues act to reset the timing of arm movements.

Oxygen delivery to skeletal muscle fibers: effects of microvascular unit structure and control mechanisms

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00278.2003 ◽

2003 ◽

Vol 285 (3) ◽

pp. H955-H963 ◽

Cited By ~ 29

Author(s):

Arthur Lo ◽

Andrew J. Fuglevand ◽

Timothy W. Secomb

Keyword(s):

Skeletal Muscle ◽

Muscle Activation ◽

Tissue Oxygenation ◽

Oxygen Sensing ◽

Full Range ◽

Muscle Fibers ◽

Motor Units ◽

Threshold Value ◽

Control Mechanisms ◽

Capillary Perfusion

The number of perfused capillaries in skeletal muscle varies with muscle activation. With increasing activation, muscle fibers are recruited as motor units consisting of widely dispersed fibers, whereas capillaries are recruited as groups called microvascular units (MVUs) that supply several adjacent fibers. In this study, a theoretical model was used to examine the consequences of this spatial mismatch between the functional units of muscle activation and capillary perfusion. Diffusive oxygen transport was simulated in cross sections of skeletal muscle, including several MVUs and fibers from several motor units. Four alternative hypothetical mechanisms controlling capillary perfusion were considered. First, all capillaries adjacent to active fibers are perfused. Second, all MVUs containing capillaries adjacent to active fibers are perfused. Third, each MVU is perfused whenever oxygen levels at its feed arteriole fall below a threshold value. Fourth, each MVU is perfused whenever the average oxygen level at its capillaries falls below a threshold value. For each mechanism, the dependence of the fraction of perfused capillaries on the level of muscle activation was predicted. Comparison of the results led to the following conclusions. Control of perfusion by MVUs increases the fraction of perfused capillaries relative to control by individual capillaries. Control by arteriolar oxygen sensing leads to poor control of tissue oxygenation at high levels of muscle activation. Control of MVU perfusion by capillary oxygen sensing permits adequate tissue oxygenation over the full range of activation without resulting in perfusion of all MVUs containing capillaries adjacent to active fibers.