Tri-dimensional and triphasic muscle organization of whole-body pointing movements.

摘要: Previous kinematic and kinetic studies revealed that, when accomplishing a whole-body pointing task beyond arm's length, modular flexible organization could represent robust solution to control simultaneously target equilibrium maintenance. Here, we investigated the underlying mechanisms that produce such coordinative structure. We monitored activity of large number muscles spread throughout subjects' bodies while they performed movements either with or without imposition postural constraints. Analyses muscle signals lied on tri-dimensional hyper-plane were temporally organized according triphasic pattern (three components, each one exhibiting single peak activation peaks being consecutive in time). Such functional synergy was found be across conditions. Also activities separate groups acting at body joint resulted tri-dimensional. In particular, those associated lower-body joints (ankle, knee hip) always presented three sequences all However, slightly different for upper-limb, suggesting moderate level flexibility movement The present findings link together, hierarchical view motor control, coordination characterizing basic synergistic organization, namely pattern.