Motor-output variability: a theory for the accuracy of rapid motor acts.

@article{Schmidt1979MotoroutputVA,
  title={Motor-output variability: a theory for the accuracy of rapid motor acts.},
  author={Richard A. Schmidt and Howard N. Zelaznik and B Hawkins and James S. Frank and John T. Quinn},
  journal={Psychological review},
  year={1979},
  volume={47 5},
  pages={
          415-51
        }
}
Theoretical accounts of the speed-accuracy trade-off in rapid movement have usually focused on within-moveme nt error detection and correction, and have consistently ignored the possibility that motor-output variability might be predictably related to movement amplitude and movement time. This article presents a theory of motor-output variability that accounts for the relationship among the movement amplitude, movement time, the mass to be moved, and the resulting movement error. Predictions… 
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