Patterns of hypermetria and terminal cocontraction during point-to-point movements demonstrate independent action of trajectory and postural controllers.

@article{Scheidt2011PatternsOH,
  title={Patterns of hypermetria and terminal cocontraction during point-to-point movements demonstrate independent action of trajectory and postural controllers.},
  author={Robert A. Scheidt and Claude Ghez and Supriya Asnani},
  journal={Journal of neurophysiology},
  year={2011},
  volume={106 5},
  pages={
          2368-82
        }
}
We examined elbow muscle activities and movement kinematics to determine how subjects combine elementary control actions in performing movements with one and two trajectory segments. In reaching, subjects made a rapid elbow flexion to a visual target before stabilizing the limb with either a low or a higher level of elbow flexor/extensor coactivity (CoA), which was cued by target diameter. Cursor diameter provided real-time biofeedback of actual muscle CoA. In reversing, the limb was to reverse… 

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