Effect of load disturbances during centrally initiated movements

• DOI: 10.1152/jn.1978.41.3.542
• Publication Date: 2017-12-24T16:12:14Z
• Authors: E. Bizzi; P. Dev; P. Morasso; A. Polit
• Keywords: Stimulus (psychology); Stretch reflex; Proprioception; Decerebrate State; Tonic (physiology)

1. We have investigated the relative contributions of mechanical and reflex mechanisms in generating forces produced by neck muscles when loads were unexpectedly applied during centrally programmed head movements monkeys. These movements, subserved well endowed with muscle spindles, are part coordinated eye-head response to appearance a stimulus animal's visual field. Our preparation was chronically vestibulectomized monkey trained make discrimination. 2. Two procedures used evaluate torque generated musculature an unexpected load disturbance applied: first, surgically interrupting afferent loop subserving action (section cervical dorsal roots) second, building mathematical model head-neck system carrying out process simulation. 3. results indicated that compensatory origin stimulated application opposing force less than 10--30% required for perfect compensation, larger fraction observed compensation due properties (inertial, viscous, elastic) musculature. The combined processes never completely compensated disturbance.