scholarly journals Features of hand-foot crawling behavior in human adults

2012 ◽  
Vol 107 (1) ◽  
pp. 114-125 ◽  
Author(s):  
M. J. MacLellan ◽  
Y. P. Ivanenko ◽  
G. Cappellini ◽  
F. Sylos Labini ◽  
F. Lacquaniti
Keyword(s):  
Spinal Cord ◽  
Neural Control ◽  
The Body ◽  
Bipedal Walking ◽  
Emg Activity ◽  
Gradual Transition ◽  
Spatiotemporal Pattern ◽  
Plantar Flexors ◽  
Pattern Generators ◽  
Hands And Feet

Interlimb coordination of crawling kinematics in humans shares features with other primates and nonprimate quadrupeds, and it has been suggested that this is due to a similar organization of the locomotor pattern generators (CPGs). To extend the previous findings and to further explore the neural control of bipedal vs. quadrupedal locomotion, we used a crawling paradigm in which healthy adults crawled on their hands and feet at different speeds and at different surface inclinations (13°, 27°, and 35°). Ground reaction forces, limb kinematics, and electromyographic (EMG) activity from 26 upper and lower limb muscles on the right side of the body were collected. The EMG activity was mapped onto the spinal cord in approximate rostrocaudal locations of the motoneuron pools to characterize the general features of cervical and lumbosacral spinal cord activation. The spatiotemporal pattern of spinal cord activity significantly differed between quadrupedal and bipedal gaits. In addition, participants exhibited a large range of kinematic coordination styles (diagonal vs. lateral patterns), which is in contrast to the stereotypical kinematics of upright bipedal walking, suggesting flexible coupling of cervical and lumbosacral pattern generators. Results showed strikingly dissimilar directional horizontal forces for the arms and legs, considerably retracted average leg orientation, and substantially smaller sacral vs. lumbar motoneuron activity compared with quadrupedal gait in animals. A gradual transition to a more vertical body orientation (increasing the inclination of the treadmill) led to the appearance of more prominent sacral activity (related to activation of ankle plantar flexors), typical of bipedal walking. The findings highlight the reorganization and adaptation of CPG networks involved in the control of quadrupedal human locomotion and a high specialization of the musculoskeletal apparatus to specific gaits.

Neural Pathways Between Sacrocaudal Afferents and Lumbar Pattern Generators in Neonatal Rats

2003 ◽  
Vol 89 (2) ◽  
pp. 773-784 ◽  
Author(s):  
I. Strauss ◽  
A. Lev-Tov
Keyword(s):  
Spinal Cord ◽  
Nmda Receptors ◽  
Neural Control ◽  
Nmda Receptor Antagonist ◽  
Neural Pathways ◽  
Synaptic Activation ◽  
Neonatal Rats ◽  
Artificial Cerebrospinal Fluid ◽  
Pattern Generators ◽  
Lumbar Cord

Projections of sacrocaudal afferents (SCA) onto lumbar pattern generators were studied in isolated spinal cords of neonatal rats. A locomotor-like pattern could be produced by SCA stimulation in the majority of the preparations. The SCA-induced lumbar rhythm was abolished after blocking synaptic transmission in the sacrococcygeal (SC) cord by bathing its segments in a low-calcium, high-magnesium artificial cerebrospinal fluid and restored when the synaptic block was alleviated by local application of calcium onto specific SC segments prior to SCA stimulation. Thus the SCA evoked lumbar rhythm involves synaptic activation of relay neurons in the SC cord. Functional activation of these relays depends on non– N-methyl-d-aspartate (NMDA) receptors because the lumbar rhythm was abolished when the non-NMDA receptor antagonist CNQX was added to the SC cord. By contrast, pharmacological block of the rhythmicity in the SC cord by specific antagonists of NMDA receptors and α1 and α2 adrenoceptors did not impair the SCA-induced lumbar rhythm. Midsagittal splitting experiments of parts of the SC and lumbar cord revealed that crossed and uncrossed ascending/propriospinal pathways are coactivated by SCA stimulation. We suggest that these pathways ascend onto the thoracolumbar cord through the lateral, ventrolateral, and ventral funiculi, because a complete block of the lumbar rhythm could only be obtained with a bilateral interruption of all of these funiculi. The relevance of our findings to the neural control of the rhythmogenic networks in the spinal cord is discussed.

scholarly journals Interlimb Coordination in Human Crawling Reveals Similarities in Development and Neural Control With Quadrupeds

2009 ◽  
Vol 101 (2) ◽  
pp. 603-613 ◽  
Author(s):  
Susan K. Patrick ◽  
J. Adam Noah ◽  
Jaynie F. Yang
Keyword(s):  
Neural Control ◽  
Force Plate ◽  
Interlimb Coordination ◽  
Limb Length ◽  
Bipedal Walking ◽  
Human Infants ◽  
Hind Limbs ◽  
Underlying Mechanisms ◽  
Hands And Feet ◽  
Coordination Patterns

The study of quadrupeds has furnished most of our understanding of mammalian locomotion. To allow a more direct comparison of coordination between the four limbs in humans and quadrupeds, we studied crawling in the human, a behavior that is part of normal human development and mechanically more similar to quadrupedal locomotion than is bipedal walking. Interlimb coordination during hands-and-knees crawling is compared between humans and quadrupeds and between human infants and adults. Mechanical factors were manipulated during crawling to understand the relative contributions of mechanics and neural control. Twenty-six infants and seven adults were studied. Video, force plate, and electrogoniometer data were collected. Belt speed of the treadmill, width of base, and limb length were manipulated in adults. Influences of unweighting and limb length were explored in infants. Infants tended to move diagonal limbs together (trot-like). Adults additionally moved ipsilateral limbs together (pace-like). At lower speeds, movements of the four limbs were more equally spaced in time, with no clear pairing of limbs. At higher speeds, running symmetrical gaits were never observed, although one adult galloped. Widening stance prevented adults from using the pace-like gait, whereas lengthening the hind limbs (hands-and-feet crawling) largely prevented the trot-like gait. Limb length and unweighting had no effect on coordination in infants. We conclude that human crawling shares features both with other primates and with nonprimate quadrupeds, suggesting similar underlying mechanisms. The greater restriction in coordination patterns used by infants suggests their nervous system has less flexibility.

Spinal Cord Maps of Spatiotemporal Alpha-Motoneuron Activation in Humans Walking at Different Speeds

2006 ◽  
Vol 95 (2) ◽  
pp. 602-618 ◽  
Author(s):  
Y. P. Ivanenko ◽  
R. E. Poppele ◽  
F. Lacquaniti
Keyword(s):  
Spinal Cord ◽  
Center Of Mass ◽  
Trunk Muscles ◽  
Emg Activity ◽  
Step Cycle ◽  
Human Spinal Cord ◽  
Spinal Segments ◽  
Motoneuron Activity ◽  
Pattern Generators ◽  
Walking Speeds

Functional MRI (fMRI) imaging of motoneuron activity in the human spinal cord is still in its infancy, and it will remain difficult to apply to walking. Here we present a viable alternative for documenting the spatiotemporal maps of α-motorneuron (MN) activity in the human spinal cord during walking, similar to the method recently reported for the cat. We recorded EMG activity from 16 to 32 ipsilateral limb and trunk muscles in 13 healthy subjects walking on a treadmill at different speeds (1–7 km/h) and mapped the recorded patterns onto the spinal cord in approximate rostrocaudal locations of the motoneuron pools. This approach can provide information about pattern generator output during locomotion in terms of segmental control rather than in terms of individual muscle control. A striking feature we found is that nearly every spinal segment undergoes at least two cycles of activation in the step cycle, thus supporting the idea of half-center oscillators controlling MN activation at any segmental level. The resulting spatiotemporal map patterns seem highly stereotyped over the range of walking speeds studied, although there were also some systematic redistributions of MN activity with speed. Bursts of MN activity were either temporally aligned across several spinal segments or switched between different segments. For example, the center of mass of MN activity in the lumbosacral levels generally shifted from rostral to caudal positions in two cycles for each step, revealing four major activation foci: two in the upper lumbar segments and two in the sacral segments. The results are consistent with the presence of at least two and possibly more pattern generators controlling the activation of lumbosacral MNs.

scholarly journals Somatosensory control of balance during locomotion in decerebrated cat

2012 ◽  
Vol 107 (8) ◽  
pp. 2072-2082 ◽  
Author(s):  
Pavel Musienko ◽  
Gregoire Courtine ◽  
Jameson E. Tibbs ◽  
Vyacheslav Kilimnik ◽  
Alexandr Savochin ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Brain Stem ◽  
Spinal Cord Stimulation ◽  
Balance Control ◽  
Dynamic Balance ◽  
Weight Bearing ◽  
The Body ◽  
Emg Activity ◽  
Somatosensory Information ◽  
The Brain

Postmammillary decerebrated cats can generate stepping on a moving treadmill belt when the brain stem or spinal cord is stimulated tonically and the hindquarters are supported both vertically and laterally. While adequate propulsion seems to be generated by the hindlimbs under these conditions, the ability to sustain equilibrium during locomotion has not been examined extensively. We found that tonic epidural spinal cord stimulation (5 Hz at L5) of decerebrated cats initiated and sustained unrestrained weight-bearing hindlimb stepping for extended periods. Detailed analyses of the relationships among hindlimb muscle EMG activity and trunk and limb kinematics and kinetics indicated that the motor circuitries in decerebrated cats actively maintain equilibrium during walking, similar to that observed in intact animals. Because of the suppression of vestibular, visual, and head-neck-trunk sensory input, balance-related adjustments relied entirely on the integration of somatosensory information arising from the moving hindquarters. In addition to dynamic balance control during unperturbed locomotion, sustained stepping could be reestablished rapidly after a collapse or stumble when the hindquarters switched from a restrained to an unrestrained condition. Deflecting the body by pulling the tail laterally induced adaptive modulations in the EMG activity, step cycle features, and left-right ground reaction forces that were sufficient to maintain lateral stability. Thus the brain stem-spinal cord circuitry of decerebrated cats in response to tonic spinal cord stimulation can control dynamic balance during locomotion using only somatosensory input.

scholarly journals A new conceptual framework for the integrated neural control of locomotor and sympathetic function: implications for exercise after spinal cord injury

2018 ◽  
Vol 43 (11) ◽  
pp. 1140-1150 ◽  
Author(s):  
Kristine C. Cowley
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Conceptual Framework ◽  
Neural Control ◽  
Neural Circuitry ◽  
The Body ◽  
Sympathetic Function ◽  
Postural Changes ◽  
Cord Injury ◽  
New Research

All mammals, including humans, are designed to produce sustained locomotor movements. Many higher centres are involved in movement, but ultimately these centres act upon a core “rhythm-generating” network within the brainstem-spinal cord. In addition, endurance-based locomotor exercise requires sympathetic neural support to maintain homeostasis and to provide needed metabolic resources. This review focuses on the roles and integration of these 2 neural systems. Part I reviews the cardiovascular, thermoregulatory, and metabolic functions under spinal sympathetic control as revealed by spinal cord injury at different levels. Part II examines the integration between brainstem-spinal sympathetic pathways and the neural circuitry producing motor rhythms. In particular, the rostroventral medulla (RVM) contains the neural circuitry that (i) integrates heart rate, contractility, and blood flow in response to postural changes; (ii) initiates and maintains cardiovascular adaptations for exercise; (iii) provides direct descending innervation to preganglionic neurons innervating the adrenal glands, white adipose tissue, and tissues responsible for cooling the body; (iv) integrates descending sympathetic drive for energy substrate mobilization (lipolysis); and (v) is the relay for descending locomotor commands arising from higher brain centres. A unifying conceptual framework is presented, in which the RVM serves as the final descending supraspinal “exercise integration centre” linking the descending locomotor command signal with the metabolic and homeostatic support needed to produce prolonged rhythmic activities. The role and rationale for an ascending sympathetic and locomotor drive from the lower to upper limbs within this framework is presented. Examples of new research directions based on this unifying framework are discussed.

scholarly journals Guillain-Barré Syndrome: A Rare Case Report

2021 ◽  
pp. 263-267
Author(s):  
Roshani Dhanvijay ◽  
Ruchira Ankar
Keyword(s):  
Spinal Cord ◽  
The United States ◽  
The Body ◽  
Guillain Barre Syndrome ◽  
Bladder Control ◽  
Guillain Barré Syndrome ◽  
Guillain Barré ◽  
Hands And Feet ◽  
Brain And Spinal Cord ◽  
The Brain

Introduction: Guillain-Barré syndrome (GBS) is a rare neurodegenerative condition in which the immune system of the body mistakenly damages a portion of the peripheral nerve system. The initial signs are general weakness and numbness in the limbs. Initial symptoms occur within a few days or weeks of infection. These symptoms can spread fast, ultimately paralyzing the entire body. The peripheral system consists of the brain and spinal cord.  The nerve network is found outside of the brain and spinal cord. GBS can range from a minor case with short weakness to a completely fatal paralysis that renders the individual unable to breathe on their own. Fortunately, even the most severe instances of GBS may be recovered from. Some people will remain feeble even after they have recovered. The majority of patients reach the peak of their weakness within the first two weeks of symptoms appearing; by the third week, 90 percent of those affected are at their weakest. Symptoms of muscle weakness include difficulty with muscles of the eyes and vision, swallowing difficulties, difficulty in speaking, or chewing, pricking or pins and needles sensations in the hands and feet, pain that can be severe, especially at night, coordination problems, and unsteadiness, abnormal heartbeat/rate or blood pressure, problems with digestion and/or bladder control, and problems with digestion and/or bladder control. Background: Guillain-Barré syndrome can affect anyone. It can attack at any age (though it is more common in adults and the elderly), and both sexes are equally susceptible to the condition. GBS is predicted to afflict one in every 100,000 people each year. GBS affects between 3,000 and 6,000 persons in the United States each year. Case Presentation: A 53 years old male patient came to the hospital with the chief complaint of weakness in all four limbs for 6 days. A patient was apparently alright 6 days back later he was experience weakness in the left side of the body following covid vaccination on 4th June, weakness was gradually progressive in nature and progress to the right side of the body after 2 days. Later on, 8th of June patient got admitted to GMC yavatmal where the routine investigation was done including a CT scan brain which normal and doctors ask for an MRI brain for which the patient and his relative had taken a DAMA discharge and brought the patient to AVBR Hospital. All investigation has been done after that the physician diagnosed the patient having Guillain barre syndrome. The patient weakness has been worse and the treatment start according to the disease condition. Medical treatment including physical therapy also been started to reducing physical weakness and the patient condition is improved day by day. Intervention: The intervention was given to the patient such as injection ceftriaxone 1 gm BD, Inj pan 40 mg OD, Inj Emset 4 mg  TDS, Inj optinurone 1 Amp in 100 ml normal saline.

Evolution and Development of a Central Pattern Generator for the Swimming of a Lamprey

1999 ◽  
Vol 5 (3) ◽  
pp. 247-269 ◽  
Author(s):  
Auke Jan Ijspeert ◽  
Jérôme Kodjabachian
Keyword(s):  
Neural Control ◽  
Fitness Function ◽  
Central Pattern Generators ◽  
The Body ◽  
Programming Approach ◽  
Two Dimensional ◽  
Developmental Programs ◽  
Cellular Division ◽  
Input Signals ◽  
Pattern Generators

This article describes the design of neural control architectures for locomotion using an evolutionary approach. Inspired by the central pattern generators found in animals, we develop neural controllers that can produce the patterns of oscillations necessary for the swimming of a simulated lamprey. This work is inspired by Ekeberg's neuronal and mechanical model of a lamprey [11] and follows experiments in which swimming controllers were evolved using a simple encoding scheme [25, 26]. Here, controllers are developed using an evolutionary algorithm based on the SGOCE encoding [31, 32] in which a genetic programming approach is used to evolve developmental programs that encode the growing of a dynamical neural network. The developmental programs determine how neurons located on a two-dimensional substrate produce new cells through cellular division and how they form efferent or afferent interconnections. Swimming controllers are generated when the growing networks eventually create connections to the muscles located on both sides of the rectangular substrate. These muscles are part of a two-dimensional mechanical simulation of the body of the lamprey in interaction with water. The motivation of this article is to develop a method for the design of control mechanisms for animal-like locomotion. Such a locomotion is characterized by a large number of actuators, a rhythmic activity, and the fact that efficient motion is only obtained when the actuators are well coordinated. The task of the control mechanism is therefore to transform commands concerning the speed and direction of motion into the signals sent to the multiple actuators. We define a fitness function, based on several simulations of the controller with different commands settings, that rewards the capacity of modulating the speed and the direction of swimming in response to simple, varying input signals. Central pattern generators are thus evolved capable of producing the relatively complex patterns of oscillations necessary for swimming. The best solutions generate traveling waves of neural activity, and propagate, similarly to the swimming of a real lamprey, undulations of the body from head to tail propelling the lamprey forward through water. By simply varying the amplitude of two input signals, the speed and the direction of swimming can be modulated.

scholarly journals Rostrocaudal Distribution of the C-Fos-Immunopositive Spinal Network Defined by Muscle Activity during Locomotion

2021 ◽  
Vol 11 (1) ◽  
pp. 69
Author(s):  
Natalia Merkulyeva ◽  
Vsevolod Lyakhovetskii ◽  
Aleksandr Veshchitskii ◽  
Oleg Gorskii ◽  
Pavel Musienko
Keyword(s):  
Spinal Cord ◽  
Locomotor Activity ◽  
Control Systems ◽  
Muscle Activity ◽  
Knee Extensors ◽  
Emg Activity ◽  
Lumbosacral Spinal Cord ◽  
Adductor Muscles ◽  
Spinal Network ◽  
Hip Flexor

The optimization of multisystem neurorehabilitation protocols including electrical spinal cord stimulation and multi-directional tasks training require understanding of underlying circuits mechanisms and distribution of the neuronal network over the spinal cord. In this study we compared the locomotor activity during forward and backward stepping in eighteen adult decerebrated cats. Interneuronal spinal networks responsible for forward and backward stepping were visualized using the C-Fos technique. A bi-modal rostrocaudal distribution of C-Fos-immunopositive neurons over the lumbosacral spinal cord (peaks in the L4/L5 and L6/S1 segments) was revealed. These patterns were compared with motoneuronal pools using Vanderhorst and Holstege scheme; the location of the first peak was correspondent to the motoneurons of the hip flexors and knee extensors, an inter-peak drop was presumably attributed to the motoneurons controlling the adductor muscles. Both were better expressed in cats stepping forward and in parallel, electromyographic (EMG) activity of the hip flexor and knee extensors was higher, while EMG activity of the adductor was lower, during this locomotor mode. On the basis of the present data, which showed greater activity of the adductor muscles and the attributed interneuronal spinal network during backward stepping and according with data about greater demands on postural control systems during backward locomotion, we suppose that the locomotor networks for movements in opposite directions are at least partially different.

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