Analysis of Movement Trajectories Focusing on the Interaction Torque in Arm Movements

We examined the systematic variation in shoulder and elbow torque, as well as movement kinematics, for horizontal-plane arm movements with direction reversals performed by normal individuals and individuals with Down syndrome. Eight neurologically normal individuals and eight individuals with Down syndrome performed horizontal, planar reversal movements to four different target locations. The four locations of the targets were chosen such that there is a systematic increase in elbow interaction torque for each of the four different target locations. This systematic increase in interaction torque has previously been shown to lead to progressively larger movement reversal errors, and trajectories that do not show a sharp reversal of direction, for movements to and from the target in patients who have proprioceptive abnormalities. We computed joint torques at the elbow and shoulder and found a high correlation between elbow and shoulder torque for the neurologically normal subjects. The ratio of joint torques varied systematically with target location. These findings extend previously reported findings of a linear synergy between shoulder and elbow joints for a variety of point-to-point movements. There was also a correlation between elbow and shoulder torque in individuals with Down syndrome, but the magnitude of the correlation was less. The ratio of joint torques changed systematically with target direction in individuals with Down syndrome but was slightly different from the ratio observed for neurologically normal individuals. The difference in the ratio was caused by the generation of proportionately more elbow torque than shoulder torque. The fingertip path of individuals with Down syndrome showed a sharp reversal in moving toward and then away from the target. In this respect, they were similar to neurologically normal individuals but dissimilar to individuals with proprioceptive deficits. Finally, we observed that individuals with Down syndrome spend proportionately more time in the vicinity of the target than normal individuals. Collectively these results show that there is a systematic relationship between joint torques at the elbow and shoulder. This relationship is present for reversal movements and is also present in individuals with Down syndrome.

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Trajectory Formation of Vertical Arm Movements through a Via-Point: A Limit of Validity of the Minimum-Jerk Model

Perceptual and Motor Skills ◽

10.2466/pms.1993.76.3.875 ◽

1993 ◽

Vol 76 (3) ◽

pp. 875-884 ◽

Cited By ~ 6

Author(s):

Taketo Furuna ◽

Hiroshi Nagasaki

Keyword(s):

Tangential Velocity ◽

Arm Movements ◽

Initial Position ◽

Kinematic Data ◽

Joint Coordination ◽

Movement Trajectories ◽

Minimum Jerk ◽

Trajectory Formation ◽

Kinematic Measurement ◽

Human Movements

The minimum-jerk model predicts the smoothest trajectory for a class of human movements and so provides us with a kinematic measurement of skilled motor performance. To establish the limits of the model's validity, the predicted and experimentally defined movement trajectories and the joint coordination were compared in two-joint arm movements, bringing the hand from the initial position to the final position through a specified point (a via-point). Kinematic data of the movements were obtained through the SELSPOT system. The movement path, tangential velocity, and coordinated change in positions of the shoulder and elbow joints evidently deviated from those predicted by the model. These results suggest that the minimum-jerk model is not valid for movements under extreme conditions which are highly dependent on musculoskeletal dynamics.

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Limitations on Coupling of Bimanual Movements Caused by Arm Dominance: When the Muscle Homology Principle Fails

Journal of Neurophysiology ◽

10.1152/jn.00778.2009 ◽

2010 ◽

Vol 103 (4) ◽

pp. 2027-2038 ◽

Cited By ~ 24

Author(s):

Natalia Dounskaia ◽

Keith G. Nogueira ◽

Stephan P. Swinnen ◽

Elizabeth Drummond

Keyword(s):

Joint Control ◽

Interaction Torque ◽

Movement Trajectories ◽

Bimanual Movements ◽

Cycling Frequency ◽

Torque Analysis ◽

Arm Dominance ◽

Bimanual Interference ◽

Control Interaction ◽

Circle Drawing

Studies of bimanual movements typically report interference between motions of the two arms and preference to perform mirror-symmetrical patterns. However, recent studies have demonstrated that the two arms differ in the ability to control interaction torque (INT). This predicts limitations in the capability to perform mirror-symmetrical movements. Here, two experiments were performed to test this prediction. The first experiment included bimanual symmetrical and asymmetrical circle drawing at two frequency levels. Unimanual circle drawing was also recorded. The increases in cycling frequency caused differences between the two arms in movement trajectories in both bimanual modes, although the differences were more pronounced in the asymmetrical compared with the symmetrical mode. Based on torque analysis, the differences were attributed to the nondominant arm's decreased capability to control INT. The intraarm differences during the symmetrical pattern of bimanual movements were similar (although more pronounced) to those during unimanual movements. This finding was verified in the second experiment for symmetrical bimanual oval drawing. Four oval orientations were used to provide variations in INT. Similar to the first experiment, increases in cycling frequency caused spontaneous deviations from perfect bimanual symmetry associated with inefficient INT control in the nondominant arm. This finding supports the limitations in performing mirror-symmetrical bimanual movements due to differences in joint control between the arms. Based on our results and previous research, we argue that bimanual interference occurs during specification of characteristics of required motion, whereas lower-level generation of muscle forces is independent between the arms. A hierarchical model of bimanual control is proposed.

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Perceiving Affect From Point-Light Displays of Arm Movements

PsycEXTRA Dataset ◽

10.1037/e501882009-259 ◽

2000 ◽

Author(s):

Frank E. Pollick ◽

Helena Paterson ◽

Andrew J. Calder ◽

Armin Bruderlin ◽

Anthony J. Sanford

Keyword(s):

Arm Movements ◽

Point Light

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Joint Angle Determinants in Aimed Arm Movements With Excess Degrees of Freedom

PsycEXTRA Dataset ◽

10.1037/e665412011-186 ◽

1992 ◽

Author(s):

Charles E. Wright ◽

Rebecca States

Keyword(s):

Degrees Of Freedom ◽

Joint Angle ◽

Arm Movements

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Faculty Opinions recommendation of The central nervous system does not minimize energy cost in arm movements.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.5667956.5686060 ◽

2010 ◽

Author(s):

Melvyn Goodale ◽

Gavin Buckingham

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Energy Cost ◽

Arm Movements ◽

The Central Nervous System

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Features of prototyping the kinematic movements of human extremities during the implementation of demonstration robots

Automation. Modern Techologies ◽

10.36652/0869-4931-2020-74-7-325-328 ◽

2020 ◽

Keyword(s):

Arm Movements ◽

Robot Arm ◽

Movement Coordination ◽

Movement Kinematic

The features of prototyping the movement kinematic of human extremities during in the implementation of demonstration robots based on a hinged three-link are considered. Keywords demonstration robot; three-link manipulator; trajectory of movement; coordination of robot arm movements

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Tri-axial accelerometry shows differences in energy expenditure and parental effort throughout the breeding season in long-lived raptors

Current Zoology ◽

10.1093/cz/zoab010 ◽

2021 ◽

Author(s):

Pascual LÓPEZ-LÓPEZ ◽

Arturo M PERONA ◽

Olga EGEA-CASAS ◽

Jon ETXEBARRIA MORANT ◽

Vicente URIOS

Keyword(s):

Energy Expenditure ◽

Parental Care ◽

Breeding Season ◽

Video Recording ◽

Experimental Manipulation ◽

Biparental Care ◽

Breeding Ecology ◽

Parental Effort ◽

Ecological Data ◽

Movement Trajectories

Abstract Cutting-edge technologies are extremely useful to develop new workflows in studying ecological data, particularly to understand animal behaviour and movement trajectories at the individual level. Although parental care is a well-studied phenomenon, most studies have been focused on direct observational or video recording data, as well as experimental manipulation. Therefore, what happens out of our sight still remains unknown. Using high-frequency GPS/GSM dataloggers and tri-axial accelerometers we monitored 25 Bonelli’s eagles (Aquila fasciata) during the breeding season to understand parental activities from a broader perspective. We used recursive data, measured as number of visits and residence time, to reveal nest attendance patterns of biparental care with role specialization between sexes. Accelerometry data interpreted as the Overall Dynamic Body Acceleration, a proxy of energy expenditure, showed strong differences in parental effort throughout the breeding season and between sexes. Thereby, males increased substantially their energetic requirements, due to the increased workload, while females spent most of the time on the nest. Furthermore, during critical phases of the breeding season, a low percentage of suitable hunting spots in eagles’ territories led them to increase their ranging behaviour in order to find food, with important consequences in energy consumption and mortality risk. Our results highlight the crucial role of males in raptor species exhibiting biparental care. Finally, we exemplify how biologging technologies are an adequate and objective method to study parental care in raptors as well as to get deeper insight into breeding ecology of birds in general.

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