Do arm postures vary with the speed of reaching?

@article{Nishikawa1999DoAP,
  title={Do arm postures vary with the speed of reaching?},
  author={Kiisa C. Nishikawa and Suzanne Elanore Turner Murray and Melanie Flanders},
  journal={Journal of neurophysiology},
  year={1999},
  volume={81 5},
  pages={
          2582-6
        }
}
Do arm postures vary with the speed of reaching? For reaching movements in one plane, the hand has been observed to follow a similar path regardless of speed. Recent work on the control of more complex reaching movements raises the question of whether a similar "speed invariance" also holds for the additional degrees of freedom. Therefore we examined human arm movements involving initial and final hand locations distributed throughout the three-dimensional (3D) workspace of the arm. Despite… 

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References

SHOWING 1-10 OF 21 REFERENCES
Moving effortlessly in three dimensions: does Donders' law apply to arm movement?
TLDR
It was found that, in general, the posture of the arm at a given hand location does depend on the starting location of the movement and that Donders' law is violated in this experimental condition.
Kinematic features of unrestrained vertical arm movements
  • C. Atkeson, J. Hollerbach
  • Psychology
    The Journal of neuroscience : the official journal of the Society for Neuroscience
  • 1985
TLDR
Unrestrained human arm trajectories between point targets have been investigated using a three-dimensional tracking apparatus, the Selspot system, and movement regions were discovered in which the hand paths were curved.
Invariant characteristics of a pointing movement in man
Simple arm movements involving forward projection of the hand toward a target were studied by measuring simultaneous wrist position in three- dimensional space and changes in elbow angle. An attempt
Two components of muscle activation: scaling with the speed of arm movement.
TLDR
Electromyographic (EMG) activity was recorded from several superficial elbow and/or shoulder muscles and the time base of rectified EMG records was normalized for movement time such that records from movements with various speeds were compressed to align the ending times of the movements.
Does the nervous system use equilibrium-point control to guide single and multiple joint movements?
TLDR
The hypothesis that the central nervous system generates movement as a shift of the limb's equilibrium posture has been corroborated experimentally in studies involving single- and multijoint motions and can now be investigated in the neurophysiological machinery of the spinal cord.
A minimum energy cost hypothesis for human arm trajectories.
TLDR
This paper presents and tests the hypothesis that trajectories are chosen to minimize metabolic energy costs, and calculated energy minimizing trajectories for a model with biarticular elbow muscles agree well with observed trajectoryories for fast movements.
A minimum energy cost hypothesis for human arm trajectories
TLDR
Calculated energy minimizing trajectories for a model with biarticular elbow muscles agree well with observed trajectoryories for fast movements, and good agreement is also obtained for slow movements if they are assumed to be performed by slower muscles.
Equilibrium-Point Control Hypothesis Examined by Measured Arm Stiffness During Multijoint Movement
TLDR
The results argue against the hypothesis that the brain sends as a motor command only an equilibrium-point trajectory similar to the actual trajectory.
Errors in pointing are due to approximations in sensorimotor transformations.
TLDR
It is proposed that errors in pointing occur because subjects implement a linear approximation to the transformation from extrinsic to intrinsic coordinates and that this transformation is one step in the process of transforming a visually derived representation of target location into an appropriate pattern of muscle activity.
A computationally efficient method for solving the redundant problem in biomechanics.
...
1
2
3
...