Eyes will be closed in a dust wind, and a dodge will be made when facing danger... Animals will run away or take protective measures by instinct in the face of outside threats. Therefore, from the point of view of adaptation and survival, all sensory information processed in the brain is for the animal to take appropriate actions.
How does the brain control our body, through the movement related neurons, to take actions? A recent study by a research group led by Prof. HU Xintian in the CAS Kunming Institute of Zoology (KIZ), offers some clues to the answers.
It is well known that the brain is a complex system made up of large amount of neurons. Every single movement we make is the result of the activities of thousands of such neurons. In other words, the motor command of a movement control system is the summation of these neuronal activities. However, little is known about the ways in which each command is expressed on the individual neurons in the system, and obviously, this is an important question that must be answered in the field of movement control study.
After developing new analyzing methods, the team carried out a quantitative study on this issue by using the monkey's eye movement control system as a model, and their work has been published on a recent issue of the Proceedings of the National Academy of Sciences (PNAS).
The research results indicate that, every motor command has been expressed in high precision on each of the premotor neurons (neurons that send inputs to the motor neurons which control the musles directly) located on the eye movement control pathway. "It not only deepens our understanding of the neural mechanism of the movements control in human, but also stirs inspirations for the design of the movement control in a robotic unit," notes Hu.
The work "is a very simple and extremely elegant study of premotor neurons within the oculomotor control system," comments a PNAS reviewer, adding the findings are compelling and absolutely fundamental to our understanding of how saccadic eye movements are controlled.