Early motor development from partially ordered neural-body dynamics: experiments with a cortico-spinal-musculo-skeletal model

Biol Cybern. 2006 Dec;95(6):589-605. doi: 10.1007/s00422-006-0127-z. Epub 2006 Nov 23.


Early human motor development has the nature of spontaneous exploration and boot-strap learning, leading to open-ended acquisition of versatile flexible motor skills. Since dexterous motor skills often exploit body-environment dynamics, we formulate the developmental principle as the spontaneous exploration of consistent dynamical patterns of the neural-body-environment system. We propose that partially ordered dynamical patterns emergent from chaotic oscillators coupled through embodiment serve as the core driving mechanism of such exploration. A model of neuro-musculo-skeletal system is constructed capturing essential features of biological systems. It consists of a skeleton, muscles, spindles, tendon organs, spinal circuits, medullar circuits (CPGs), and a basic cortical model. Through a series of experiments with a minimally simple body model, it is shown that the model has the capability of generating partially ordered behavior, a mixture of chaotic exploration and ordered entrained patterns. Models of self-organizing cortical areas for primary somatosensory and motor areas are introduced. They participate in the explorative learning by simultaneously learning and controlling the movement patterns. A scaled up version of the model, a human infant model, is constructed and put through preliminary experiments. Some meaningful motor behavior emerged including rolling over and crawling-like motion. The results show the possibility that a rich variety of meaningful behavior can be discovered and acquired by the neural-body dynamics without pre-defined coordinated control circuits.

MeSH terms

  • Behavior / physiology
  • Humans
  • Joints / physiology
  • Learning / physiology
  • Mathematics
  • Models, Biological*
  • Motor Activity / physiology*
  • Musculoskeletal Physiological Phenomena*
  • Musculoskeletal System* / anatomy & histology
  • Nerve Net / physiology
  • Nonlinear Dynamics