Cognitive Processing

, Volume 6, Issue 1, pp 15–24 | Cite as

Neural representations of motor plans, desired trajectories, and controlled objects



Traditional theories of motor control view it as a serial process of planning and execution situated at the end of a larger serial process of perceptual representation and cognitive decision-making. Here, I examine the assumption that “planning” and “execution” are distinct processes separated by a neural representation of a “desired trajectory”. I propose that neural data do not support the existence of a desired trajectory or of any pre-generated plan other than a crude representation of the intended motion of a controlled object. That representation appears to be more strongly involved in decision-making processes than in the control of a specific movement, and it does not appear to be converted into a detailed motor command until after the movement begins, even in well-trained tasks. Thus, one is led to question whether the traditional distinction between decision-making, planning, and motor execution is a useful foundation for interpreting neural data and generating computational theories of motor control.


Planning Motor control Theory 


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Copyright information

© Marta Olivetti Belardinelli and Springer-Verlag 2005

Authors and Affiliations

  1. 1.Dept. de physiologieUniversité de MontréalMontréalCanada

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