Mesoscale neural model of human spinal cord, muscle receptors, muscle dynamics and standing control biomechanics. This recently published paper starts from neuronal ionic channels to model spinal cord neurons and ends at studying human postural control during quiet stance. It represents a closed loop system, with feedback achieved through appropriate muscle spindle and Golgi tendon organ models. It is a mesoscale model and it was successfully validated both at the individual level and the overall behavior level. Spinal cord neurons (motoneurons and excitatory and inhibitory interneurons) are modeled based on ionic channel dynamics, synapses have dynamic properties, afferent and efferent axons introduce delays, muscles and tendons are modeled based on human data, appropriate models of muscle spindles and Golgi tendon organs provide sensory feedback to the spinal cord. Brain commands on the spinal cord are modeled through Gamma point processes with appropriate parameters.

From an overall theoretical view, the system is composed of nonlinear elements, it is stochastic and has delays and is described by approximately 5000 differential equations.

Among its many new results, one is that a mixture of intermittent and continuous motor control may arise from the overall dynamics of the closed loop system, without influence from the brain. Elias, L.A., Watanabe, R.N. Kohn, A.F., 2014 (November). Spinal Mechanisms May Provide a Combination of Intermittent and Continuous Control of Human Posture: Predictions from a Biologically Based Neuromusculoskeletal Model http://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.100394... Andre Fabio Kohn, Ph.D. Professor of Biomedical Engineering and Neuroscience University of Sao Paulo, Brazil www.leb.usp.br 2015-01-30 18:36 GMT-02:00 André Fabio Kohn <andfkohn@gmail.com>:

This recently published paper starts from neuronal ionic channels to model spinal cord neurons and ends at studying human postural control during quiet stance. It represents a closed loop system, with feedback achieved through appropriate muscle spindle and Golgi tendon organ models. It is a mesoscale model and it was successfully validated both at the individual level and the overall behavior level. Spinal cord neurons (motoneurons and excitatory and inhibitory interneurons) are modeled based on ionic channel dynamics, synapses have dynamic properties, afferent and efferent axons introduce delays, muscles and tendons are modeled based on human data, appropriate models of muscle spindles and Golgi tendon organs provide sensory feedback to the spinal cord. Brain commands on the spinal cord are modeled through Gamma point processes with appropriate parameters.

From an overall theoretical view, the system is composed of nonlinear elements, it is stochastic and has delays and is described by approximately 5000 differential equations.

Among its many new results, one is that a mixture of intermittent and continuous motor control may arise from the overall dynamics of the closed loop system, without influence from the brain.

Elias, L.A., Watanabe, R.N. Kohn, A.F., 2014 (November). Spinal Mechanisms May Provide a Combination of Intermittent and Continuous Control of Human Posture: Predictions from a Biologically Based Neuromusculoskeletal Model

http://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.100394...

Andre Fabio Kohn, Ph.D.

Professor of Biomedical Engineering and Neuroscience

University of Sao Paulo, Brazil

www.leb.usp.br