Activity of precentral neurons during torque-triggered hand movements in awake primates

1979 ◽  
Vol 57 (2) ◽  
pp. 174-184 ◽  
Author(s):  
Y. C. Wong ◽  
H. C. Kwan ◽  
J. T. Murphy
Keyword(s):  
Wrist Joint ◽  
Wrist Flexion ◽  
Somatosensory Stimulation ◽  
Sensory Stimuli ◽  
Neuronal Populations ◽  
Supportive Role ◽  
Flexion Extension ◽  
Cortical Responses ◽  
Early Portion ◽  
Temporally Correlated

In monkeys performing a handle-repositioning task involving primarily wrist flexion–extension (F–E) movements after a torque perturbation was delivered to the handle, single units were recorded extracellularly in the contralateral precentral cortex. Precentral neurons were identified by passive somatosensory stimulation, and were classified into five somatotopically organized populations. Based on electromyographic recordings, it was observed that flexors and extensors about the wrist joint were specifically involved in the repositioning of the handle, while many other muscles which act at the wrist and other forelimb joints were involved in the task in a supportive role. In precentral cortex, all neuronal responses observed were temporally correlated to both the sensory stimuli and the motor responses. Visual stimuli, presented simultaneously with torque perturbations, did not affect the early portion of cortical responses to such torque perturbations. In each of the five somatotopically organized neuronal populations, task-related neurons as well as task-unrelated ones were observed. A significantly larger proportion of wrist (F–E) neurons was related to the task, as compared with the other, nonwrist (F–E) populations. The above findings were discussed in the context of a hypothesis for the function of precentral cortex during voluntary limb movement in awake primates. This hypothesis incorporates a relationship between activities of populations of precentral neurons, defined with respect to their responses to peripheral events at or about single joints, and movements about the same joint.

Temporal characteristics of torque-triggered neuronal responses in primate precentral cortex

1980 ◽  
Vol 58 (7) ◽  
pp. 778-786 ◽  
Author(s):  
Y. C. Wong ◽  
H. C. Kwan ◽  
J. T. Murphy
Keyword(s):  
Visual Information ◽  
Sensory Stimulation ◽  
Functional Coupling ◽  
Video Display ◽  
Neuronal Responses ◽  
Wrist Flexion ◽  
Motor Tasks ◽  
Neuronal Populations ◽  
Flexion Extension ◽  
Two Populations

Adult monkeys were trained to perform a restorative movement about the wrist following a torque disturbance. The movement was guided by visual information on a video display. Recordings were made from single neurons in the forelimb area of precentral cortex. Individual neurons were identified with respect to functional coupling to single forelimb joints by means of passive sensory stimulation and intracortical microstimulation. Neurons were classified as wrist (flexion–extension (F–E)) and nonwrist (F–E). Statistical analyses of activities of these two populations revealed that those belonging to the wrist (F–E) population exhibited a lower response variability than those belonging to the nonwrist (F–E) neurons. This was true with respect to both the sensory event (perturbation) and the motor event (restorative movement) at the wrist. The results thus provide additional evidence in support of the hypothesis that neuronal populations in precentral cortex which are somatotopically identified are preferentially utilized in voluntary motor tasks.

scholarly journals Classification of the Angular Position During Wrist Flexion-extension Based on EMG Signals

2021 ◽  
Vol 25 ◽  
Author(s):  
María Alexandra Fajardo-Perdomo ◽  
Verónica Guardo-Gómez ◽  
Alvaro David Orjuela-Cañón ◽  
Andrés Felipe Ruiz-Olaya
Keyword(s):  
Pattern Recognition ◽  
Wrist Joint ◽  
Angular Position ◽  
Recognition Algorithm ◽  
Ar Model ◽  
Model Parameters ◽  
Wrist Flexion ◽  
Pattern Recognition Algorithm ◽  
Time Frequency ◽  
Flexion Extension

Objective: To evaluate a group of features in a myoelectric pattern recognition algorithm to differentiate between five angular positions of the wrist during flexion-extension movements. Materials and Methods: An experimental configuration was made to capture the EMG and wrist joint angle related to flexion-extension movements. After that, a myoelectric pattern recognition algorithm based on a multilayer perceptron artificial neural network (ANN) was implemented. Three different groups were used: Time domain characteristics, autoregressive (AR) model parameters, and representation of time frequency using Wavelet transform (WT). Results and Discussion: The experimental results of 10 healthy subjects indicate that the coefficients of the AR models offer the best parameters for classification, with a differentiation rate of 78 % for the five angular positions studied. The combination of frequency and time frequency resulted in a differentiation rate that reached 82 %. Conclusions: An algorithm based on pattern recognition of EMG signals was used to carry out a comparative study of groups of features that allow for the differentiation of the angular position of the wrist in terms of flexion-extension movements. The method has the potential for application in the field of rehabilitation engineering to detect the user’s movement intent.

Rebalancing the tetraplegic wrist using extensor carpi ulnaris-tenodesis

2012 ◽  
Vol 38 (1) ◽  
pp. 22-28 ◽  
Author(s):  
C. Reinholdt ◽  
J. Fridén
Keyword(s):  
Grip Strength ◽  
Motion Correction ◽  
Wrist Joint ◽  
Cervical Spinal Cord ◽  
Wrist Flexion ◽  
Extensor Carpi Ulnaris ◽  
Flexion Extension ◽  
Cord Injury ◽  
Joint Flexion ◽  
Flexion And Extension

Patients with cervical spinal cord injury and tetraplegia often present with a radial deviation deformity of the wrist owing to impaired active wrist flexion and extension. Tenodesis of the extensor carpi ulnaris can help optimize grip strength. The purpose of the study was to compare reconstruction of the grip with and without extensor carpi ulnaris-tenodesis, as well as evaluating the outcome of the procedure. The grip strength of the group with tenodesis of the extensor carpi ulnaris was twice as strong as of the group without the tenodesis and with similar wrist joint flexion–extension range of motion. Correction of the wrist deformity enables a more ergonomic use of the hand. This may also help prevent shoulder pain, which is common among patients with tetraplegia.

THE THREE-DIMENSIONAL MOVEMENT CORRELATIONS BETWEEN ELBOW AND WRIST JOINT AND ANTHROPOMETRIC DETERMINANTS

2018 ◽  
Vol 18 (02) ◽  
pp. 1850013 ◽  
Author(s):  
WEI WANG ◽  
DONGMEI WANG ◽  
CHENGHUI LAI
Keyword(s):  
Multiple Regression ◽  
Wrist Joint ◽  
Three Dimensional ◽  
Elbow Flexion ◽  
Wrist Flexion ◽  
Factors Affecting ◽  
Bivariate Correlation ◽  
Flexion Extension ◽  
Joint Motions ◽  
The Relationship

This study aimed to investigate three-dimensional (3D) kinematic characteristics of elbow and wrist motions, the relationship between them, and the anthropometric factors affecting them. Using motion capture system, this study measured and calculated the 3D angles of elbow flexion/extension, elbow pronation/supination, wrist flexion/extension, and wrist adduction/abduction of 40 healthy young adults. The study measured nine anthropometric variables and used unpaired [Formula: see text]-tests to assess gender difference. Also, bivariate correlation tests and step-wise multiple regression analyses were performed between joint ranges and anthropometric variables, as well as different joint motions. Results showed two opposite patterns occurred during elbow flexion/extension. The study found a correlation between the range of elbow flexion/extension and the range of elbow pronation/supination that occurred during elbow flexion/extension. Additionally, the study tested joint correlations between the four joint motions. Finally, the study established bivariate and multiple regression relationships between range of elbow motions and anthropometric factors. This research presented an unrecognized pattern of 3D elbow flexion/extension, and associations between various anthropometric factors and different joint motions. These findings can contribute to the design of orthosis of upper extremities and the rehabilitation of joint mobility.

scholarly journals Wrist Position Sense in Two Dimensions: Between-Hand Symmetry and Anisotropic Accuracy Across the Space

2021 ◽  
Vol 15 ◽  
Author(s):  
Giulia A. Albanese ◽  
Michael W. R. Holmes ◽  
Francesca Marini ◽  
Pietro Morasso ◽  
Jacopo Zenzeri
Keyword(s):  
Wrist Joint ◽  
Position Sense ◽  
Two Dimensions ◽  
Joint Position ◽  
Wrist Flexion ◽  
Ulnar Deviation ◽  
Target Direction ◽  
Wrist Position ◽  
Flexion Extension ◽  
Combined Movements

A deep investigation of proprioceptive processes is necessary to understand the relationship between sensory afferent inputs and motor outcomes. In this work, we investigate whether and how perception of wrist position is influenced by the direction along which the movement occurs. Most previous studies have tested Joint Position Sense (JPS) through 1 degree of freedom (DoF) wrist movements, such as flexion/extension (FE) or radial/ulnar deviation (RUD). However, the wrist joint has 3-DoF and many activities of daily living produce combined movements, requiring at least 2-DoF wrist coordination. For this reason, in this study, target positions involved movement directions that combined wrist flexion or extension with radial or ulnar deviation. The chosen task was a robot-aided Joint Position Matching (JPM), in which blindfolded participants actively reproduced a previously passively assumed target joint configuration. The JPM performance of 20 healthy participants was quantified through measures of accuracy and precision, in terms of both perceived target direction and distance along each direction of movement. Twelve different directions of movement were selected and both hands tested. The left and right hand led to comparable results, both target extents and directions were differently perceived according to the target direction on the FE/RUD space. Moreover, during 2-DoF combined movements, subjects’ perception of directions was impaired when compared to 1-DoF target movements. In summary, our results showed that human perception of wrist position on the FE/RUD space is symmetric between hands but not isotropic among movement directions.

scholarly journals FEATURES OF JOINT MOBILITY IN SKIERS AND SKATERS

2019 ◽  
Vol 19 (1) ◽  
pp. 29-35
Author(s):  
A Postnikova ◽  
Yu Potekhina ◽  
A Kurnikova ◽  
E Tregubova ◽  
D Mokhov
Keyword(s):  
Wrist Joint ◽  
Plantar Flexion ◽  
High Amplitude ◽  
Joint Mobility ◽  
Wrist Flexion ◽  
Flexion Extension ◽  
Athletic Shoes ◽  
Ambiguous Effect ◽  
Nonparametric Statistical ◽  
Flexion And Extension

Aim. Different sports have an ambiguous effect on joint mobility. This article deals with identifying the characteristics of limb joint mobility in skiers and skaters. Materials and methods. 46 athletes (27 skiers and 19 skaters) aged 18–24 participated in the study. All athletes had no complaints regarding their musculoskeletal system. The volume of movements in limb joints was measured with a goniometer. When measuring the angles of flexion and extension of the wrist, as well as plantar flexion and extension, the amplitude was estimated both in active and passive motion. The data obtained were processed with Statistica 10.0 application package and nonparametric statistical methods. Results. In all parameters of the wrist joint (except for passive flexion), statistically significant greater mobility was revealed in skiers (p < 0.0001). The amplitude of active knee flexion was prevalent in skaters (p < 0.0001). Plantar flexion / extension (both active and passive) was also higher in skaters (p < 0.0001) than in skiers. The function of the ankle joint in skaters bears the imprint of a stable motor specialization, which is manifested in the extremely high amplitude of foot extension. In both groups, the angle of wrist flexion, the angle of retraction in the hip joint and the angle of plantar flexion exceeded the norms. This is because these joints are the most used both in skiers and skaters. Conclusions. The features of joint mobility are associated with specific athletic shoes and locomotor specialization for skiers and skaters. Skiers demonstrate the increased mobility of wrist joints, while skaters possess the increased mobility of the knee and ankle.

scholarly journals Multi–Joint Angles Estimation of Forearm Motion Using a Regression Model

2021 ◽  
Vol 15 ◽  
Author(s):  
Zixuan Qin ◽  
Sorawit Stapornchaisit ◽  
Zixun He ◽  
Natsue Yoshimura ◽  
Yasuharu Koike
Keyword(s):  
Real Time ◽  
Transfer Learning ◽  
Wrist Joint ◽  
Joint Motion ◽  
Wrist Flexion ◽  
Joint Angles ◽  
Real Time Control ◽  
Hand Grip ◽  
Proposed Model ◽  
Flexion Extension

To improve the life quality of forearm amputees, prosthetic hands with high accuracy, and robustness are necessary. The application of surface electromyography (sEMG) signals to control a prosthetic hand is challenging. In this study, we proposed a time-domain CNN model for the regression prediction of joint angles in three degrees of freedom (3-DOFs, include two wrist joint motion and one finger joint motion), and five-fold cross validation was used to evaluate the correlation coefficient (CC). The CC value results of wrist flexion/extension motion obtained from 10 participants was 0.87–0.92, pronation/supination motion was 0.72–0.95, and hand grip/open motion was 0.75–0.94. We backtracked the fully connected layer weights to create a geometry plot for analyzing the motion pattern to investigate the learning of the proposed model. In order to discuss the daily updateability of the model by transfer learning, we performed a second experiment on five of the participants in another day and conducted transfer learning based on smaller amount of dataset. The CC results improved (wrist flexion/extension was 0.90–0.97, pronation/supination was 0.84–0.96, hand grip/open was 0.85–0.92), suggesting the effectiveness of the transfer learning by incorporating the small amounts of sEMG data acquired in different days. We compared our CNN-based model with four conventional regression models, the result illustrates that proposed model significantly outperforms the four conventional models with and without transfer learning. The offline result suggests the reliability of the proposed model in real-time control in different days, it can be applied for real-time prosthetic control in the future.

Activity of identified wrist-related pallidal neurons during step and ramp wrist movements in the monkey

1990 ◽  
Vol 64 (6) ◽  
pp. 1892-1906 ◽  
Author(s):  
I. Hamada ◽  
M. R. DeLong ◽  
N. Mano
Keyword(s):  
Peak Velocity ◽  
Wrist Joint ◽  
Discharge Rate ◽  
Body Parts ◽  
Wrist Flexion ◽  
Wrist Movement ◽  
Joint Rotation ◽  
Somatosensory Stimulation ◽  
Temporal Coupling ◽  
Movement Type

1. The activity of globus pallidus (GP) neurons (n = 1,117) was studied in two monkeys to reexamine the relation of neuronal activity to movement type (slow vs. fast) while they performed both a visually guided step and ramp wrist tracking task. To select neurons specifically related to wrist movements, we employed both a somatosensory examination of individual body parts and a statistical analysis of the strength of temporal coupling of neuronal discharges to active wrist movement. 2. Neuronal responses to somatosensory stimulation were studied in 1,000 high-frequency GP neurons, of which 686 exhibited clear responses to manipulation of body parts. Of the latter, 336 responded to passive manipulation of forelimb joints and 58 selectively to passive flexion or extension of the wrist. 3. In the external segment of GP (GPe), most neurons responding to passive wrist movement were found to be clustered in four to five adjacent, closely positioned (separated by 200 microns) tracks in single coronal planes. The clusters were irregular in shape with a maximal width of 800-1,000 microns. Separate clusters of neurons responsive to passive wrist movement were identified in planes 3 mm apart in one monkey and in planes 500 microns apart in the other. Multiple clusters of neurons were also found for neurons responsive to joints other than the wrist. These findings suggest a more discrete and complex representation of individual joints in the primate GP than previously conceived. 4. During the performance of the wrist flexion and extension task, 92 neurons showed clear and consistent changes in activity. For these neurons we measured, with a statistical method on a trial-by-trial basis, the strength of temporal coupling between the onset of active wrist movement and the onset of change in neuronal discharge rate. Fifteen neurons showed changes in activity time-locked to the onset of active wrist movement. 5. Twelve pallidal neurons were classified as “wrist-related” based on their movement-locked changes in discharge during task performance and their clear responses to passive wrist joint rotation on examination. All of these neurons exhibited statistically significant modulation of their discharge rate during both fast (peak velocity 97–205 degrees/s) and slow (peak velocity 20–62 degrees/s) wrist movements in the task. The amplitudes of modulation were larger during fast wrist movement than slow movement. These results suggest that the basal ganglia motor circuit plays a similar, rather than an exclusive, role in the control of slow and fast limb movements.

scholarly journals Design and Development of Continuous Passive Motion (CPM) for Fingers and Wrist Grounded-Exoskeleton Rehabilitation System

2021 ◽  
Vol 11 (2) ◽  
pp. 815
Author(s):  
Husam Almusawi ◽  
Géza Husi
Keyword(s):  
Experimental Testing ◽  
Hand Movement ◽  
Evaluation Process ◽  
Continuous Passive Motion ◽  
Wrist Flexion ◽  
Design And Development ◽  
Passive Motion ◽  
Assistive Robots ◽  
Flexion Extension ◽  
Design Characteristics

Impairments of fingers, wrist, and hand forearm result in significant hand movement deficiencies and daily task performance. Most of the existing rehabilitation assistive robots mainly focus on either the wrist training or fingers, and they are limiting the natural motion; many mechanical parts associated with the patient’s arms, heavy and expensive. This paper presented the design and development of a new, cost-efficient Finger and wrist rehabilitation mechatronics system (FWRMS) suitable for either hand right or left. The proposed machine aimed to present a solution to guide individuals with severe difficulties in their everyday routines for people suffering from a stroke or other motor diseases by actuating seven joints motions and providing them repeatable Continuous Passive Motion (CPM). FWRMS approach uses a combination of; grounded-exoskeleton structure to provide the desired displacement to the hand’s four fingers flexion/extension (F/E) driven by an indirect feed drive mechanism by adopting a leading screw and nut transmission; and an end-effector structure to provide angular velocity to the wrist flexion/ extension (F/E), wrist radial/ulnar deviation (R/U), and forearm supination/pronation (S/P) driven by a rotational motion mechanism. We employed a single dual-sided actuator to power both mechanisms. Additionally, this article presents the implementation of a portable embedded controller. Moreover, this paper addressed preliminary experimental testing and evaluation process. The conducted test results of the FWRMS robot achieved the required design characteristics and executed the motion needed for the continuous passive motion rehabilitation and provide stable trajectories guidance by following the natural range of motion (ROM) and a functional workspace of the targeted joints comfortably for all trainable movements by FWRMS.

scholarly journals Accuracy and repeatability of wrist joint angles in boxing using an electromagnetic tracking system

2019 ◽  
Vol 23 (1) ◽  
Author(s):  
Ian T. Gatt ◽  
Tom Allen ◽  
Jon Wheat
Keyword(s):  
Wrist Joint ◽  
Tracking System ◽  
Testing Procedure ◽  
Electromagnetic Tracking ◽  
Good Reliability ◽  
Flexion Extension ◽  
In Vivo Testing ◽  
Accuracy And Repeatability ◽  
Electromagnetic Tracking System

AbstractThe hand-wrist region is reported as the most common injury site in boxing. Boxers are at risk due to the amount of wrist motions when impacting training equipment or their opponents, yet we know relatively little about these motions. This paper describes a new method for quantifying wrist motion in boxing using an electromagnetic tracking system. Surrogate testing procedure utilising a polyamide hand and forearm shape, and in vivo testing procedure utilising 29 elite boxers, were used to assess the accuracy and repeatability of the system. 2D kinematic analysis was used to calculate wrist angles using photogrammetry, whilst the data from the electromagnetic tracking system was processed with visual 3D software. The electromagnetic tracking system agreed with the video-based system (paired t tests) in both the surrogate (< 0.2°) and quasi-static testing (< 6°). Both systems showed a good intraclass coefficient of reliability (ICCs > 0.9). In the punch testing, for both repeated jab and hook shots, the electromagnetic tracking system showed good reliability (ICCs > 0.8) and substantial reliability (ICCs > 0.6) for flexion–extension and radial-ulnar deviation angles, respectively. The results indicate that wrist kinematics during punching activities can be measured using an electromagnetic tracking system.

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