Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Search research articles

Related Experiment Videos

Cosine tuning minimizes motor errors.

Emanuel Todorov¹

¹Gatsby Computational Neuroscience Unit, University College London, London, UK. emo@gatsby.ucl.ac.uk

Neural Computation

|May 22, 2002

Summary

Cosine tuning in the motor system minimizes force production errors by leveraging neuromotor noise scaling. This principle explains muscle activation and neuron firing, supported by experimental data.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Efficient computation of optimal actions.

Proceedings of the National Academy of Sciences of the United States of America·2009

Same author

Structured variability of muscle activations supports the minimal intervention principle of motor control.

Journal of neurophysiology·2009

Same author

Probabilistic inference of multijoint movements, skeletal parameters and marker attachments from diverse motion capture data.

IEEE transactions on bio-medical engineering·2007

Same author

Evidence for the flexible sensorimotor strategies predicted by optimal feedback control.

The Journal of neuroscience : the official journal of the Society for Neuroscience·2007

Same author

From task parameters to motor synergies: A hierarchical framework for approximately-optimal control of redundant manipulators.

Journal of robotic systems·2007

Same author

Hierarchical Feedback and Learning for Multi-joint Arm Movement Control.

Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual Conference·2007

Area of Science:

Neuroscience
Motor Control
Biomechanics

Background:

Cosine tuning is a widespread phenomenon in motor control.
The underlying reasons for its prevalence remain incompletely understood.
Existing models do not fully account for neuromotor noise characteristics.

Purpose of the Study:

To explain the origin of cosine tuning in the motor system.
To demonstrate how cosine tuning minimizes errors in force production.
To link neuromotor noise scaling to optimal muscle activation patterns.

Main Methods:

Developed a neuromotor noise model based on empirically observed linear scaling (standard deviation proportional to the mean).
Analyzed force production with single versus redundant actuators (e.g., one vs. two hands).
Derived optimal activation profiles under various conditions (dimensionality, noise, cocontraction).

Main Results:

Neuromotor noise scaling predicts reduced force errors with redundant actuators.
The optimal activation profile under the noise model is a (truncated) cosine function.
Model predictions align with experimental data, including force bias and tuning characteristics.

Conclusions:

Cosine tuning naturally arises from the principle of minimizing expected force errors.
The model provides a unified explanation for cosine tuning across diverse motor control scenarios.
This framework offers insights into neural control of movement and muscle activation.

Related Experiment Videos