Skeletomotor subsystems

Skeletomotor movements can be divided into five subsystems, each having its own independent mechanism and purpose. The subsystems are: 1. Reflex 2. Position 3. Velocity 4. Pursuit 5. Simultaneous. Reflex movements are rapid, stereotyped, inflexible and specific in terms of stimulus and response. Position movements are made to a target or certain position, with or without a load. A mechanism is proposed by which the Basal Ganglia program positioning movements into the primary movement and any load is compensated for by the stretch reflexes. Velocity movements are throwing movements and a mechanism is proposed by which the Cerebellum programs velocity into the basic, primary movement. A mechanism for Pursuit movements is proposed by which sensory and pursuit neurons activate velocity neurons whose activity drives the motor pathways to make pursuit movements. Simultaneous movements could be under the direction of the Prefrontal Cortex utilizing sensory feedback and interhemispheric transfer of information. A subcortical or cerebellar pattern generator could be set up for movements such as walking and running. The purpose of this division is to provide a guide for research and to aid in the understanding and treatment of diseases and injuries that affect the motor system.