Motor Planning

  title={Motor Planning},
  author={Aaron L. Wong and Adrian M. Haith and John W. Krakauer},
  journal={The Neuroscientist},
  pages={385 - 398}
Motor planning colloquially refers to any process related to the preparation of a movement that occurs during the reaction time prior to movement onset. However, this broad definition encompasses processes that are not strictly motor-related, such as decision-making about the identity of task-relevant stimuli in the environment. Furthermore, the assumption that all motor-planning processes require processing time, and can therefore be studied behaviorally by measuring changes in the reaction… 

Figures from this paper

A motor planning stage represents the shape of upcoming movement trajectories.

It is found that the preparation of intentionally curved reaching movements that navigate paths around obstacles incurred a large reaction-time cost, which could not be attributed to nonmotor task requirements and was independent of the execution difficulty of the movement.

Conservation of preparatory neural events in monkey motor cortex regardless of how movement is initiated

The findings support the hypothesis that an appropriate preparatory state is consistently achieved before movement onset, and reveal that this process can consume surprisingly little time.

A switching cost for motor planning.

It is found that randomly changing thewidth of a target over the course of a reaching experiment prevents the motor system from updating the endpoint of movements on the basis of the performance on the previous trial if the width of the target has changed.

Human Somatosensory Cortex Is Modulated during Motor Planning

It is found through a convergence of experiments and analyses, that the planning of object manipulation tasks, in addition to modulating the activity in the motor cortex, changes the state of neural activity in different subfields of the human S1.

Motor Learning.

Two classes of emerging research paradigms are discussed-learning of arbitrary visuomotor mappings de novo and learning to execute movements with improved acuity-that more effectively address the acquisition of motor skill.

Sequence learning is driven by improvements in motor planning

The findings show that learning effects in a sequence production task can be attributed to an enhanced ability to plan upcoming movements, and support the view that motor sequence learning effects are best characterized by improvements in planning processes that occur both before and concurrently with motor execution.

Prolonged reaction times help to eliminate residual errors in visuomotor adaptation

Evidence is found that emphasizing explicit re-aiming strategies (and concomitantly increasing planning time) also lead to complete asymptotic learning, supporting the hypothesis that incomplete adaptation is, in part, the result of an intrinsic speed-accuracy trade-off.

Movement related sensory feedback is not necessary for learning to execute a motor skill

Sequence learning is driven by improvements in motor planning.

The findings show that learning effects in a sequence production task can be attributed to an enhanced ability to plan upcoming movements, and support the view that motor sequence learning effects are best characterized by improvements in planning processes that occur both before and concurrently with motor execution.

Target Uncertainty During Motor Decision-Making: The Time Course of Movement Variability Reveals the Effect of Different Sources of Uncertainty on the Control of Reaching Movements

The findings suggest that both the level and source of uncertainty have a significant effect on the processing of potential action plans during motor decision-making, which can be revealed through the analysis of the time course of movement variability at the end-effector level.



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

  • P. Cisek
  • Psychology, Biology
    Cognitive Processing
  • 2004
It is proposed 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.

Monkey primary motor and premotor cortex: single-cell activity related to prior information about direction and extent of an intended movement.

Behavioral data support a parametric conception of motor programming, i.e., that the programming of the different movement parameters results from assembling separate processes of different duration, compatible with the model in which programming processes are serially and hierachically ordered.

Deliberation in the Motor System: Reflex Gains Track Evolving Evidence Leading to a Decision

Evidence is provided for the continuous flow of an evolving decision variable to the motor system in humans and a continuous process linking the evolving computations associated with decision making and sensorimotor control is supported.

Distinct Representations of a Perceptual Decision and the Associated Oculomotor Plan in the Monkey Lateral Intraparietal Area

The results suggest that perceptual decision-making and action selection are different brain processes that only appear to be inseparable under particular behavioral contexts.

Preparation for movement: neural representations of intended direction in three motor areas of the monkey.

Compared the functional properties of neurons in three interrelated motor areas that have been implicated in the planning and execution of visually guided limb movements, the majority of cells with task-related preparatory activity showed selective activation in anticipation of elbow movements in a particular direction.

Prior information in motor and premotor cortex: activity during the delay period and effect on pre-movement activity.

A major component of the movement-related activity in both MI and PMd is not susceptible to modification by prior information and is indivisibly coupled temporally to movement execution.

Hand path priming in manual obstacle avoidance: evidence for abstract spatiotemporal forms in human motor control.

The results are consistent with the hypothesis that the control of movement sequences relies on abstract spatiotemporal forms and support the view that motor programming is largely achieved by changing just those features that distinguish the next movement to be made from the movement that was just made.