Probabilistic Movement Models Show that Postural Control Precedes and Predicts Volitional Motor Control

Research output: Contribution to journalArticleResearchpeer-review

Authors

External Organisational units

  • Technische Universität Darmstadt
  • Department for Nanostructured Materials, Jožef Stefan Institute
  • Max-Planck Institute for Intelligent Systems

Abstract

Human motor skill learning is driven by the necessity to adapt to new situations. While supportive contacts are essential for many tasks, little is known about their impact on motor learning. To study the effect of contacts an innovative full-body experimental paradigm was established. The task of the subjects was to reach for a distant target while postural stability could only be maintained by establishing an additional supportive hand contact. To examine adaptation, non-trivial postural perturbations of the subjects’ support base were systematically introduced. A novel probabilistic trajectory model approach was employed to analyze the correlation between the motions of both arms and the trunk. We found that subjects adapted to the perturbations by establishing target dependent hand contacts. Moreover, we found that the trunk motion adapted significantly faster than the motion of the arms. However, the most striking finding was that observations of the initial phase of the left arm or trunk motion (100–400 ms) were sufficient to faithfully predict the complete movement of the right arm. Overall, our results suggest that the goal-directed arm movements determine the supportive arm motions and that the motion of heavy body parts adapts faster than the light arms.

Details

Original languageEnglish
Article number28455 / 6694
Number of pages12
JournalScientific reports (e-only)
Volume6.2016
Issue number1
DOIs
Publication statusPublished - 16 Apr 2020
Externally publishedYes