6533b7d4fe1ef96bd1262f35

RESEARCH PRODUCT

Improving operational performance in altered gravity

subject

description

Human motor adaptation is crucial to remain efficient when exposed to unfamiliar environments. In these contexts, the efficient strategies developed by the brain to optimise movement can prove deficient. Dexterous manual movement execution in space therefore require the learning of new coordinated motor actions. Traditionally, adaptation mechanisms are tested in laboratory using robotic devices that disturb the limb specifically involved in the task while the dynamics of the rest of the body remain unchanged. Although participants build a more accurate representation of the task over repetitions, these approaches are limiting as they do not reflect the ecological adjustment to globally modified dynamics. The aim of this doctoral dissertation is to better understand basic motor adaptation and to provide useful information for developing solutions that optimise actions when faced with a constraining environment. To do this, we first aimed to characterize gravity integration within the central nervous system. Then, we tested the impact of local gravity compensation while the rest of the body is immersed in an extreme environment (0 and 1.8g, induced in parabolic flight). To this end, we designed a motorised system that locally recreates terrestrial sensory information (1g) at the level of the limb involved in a simple pointing task. Our results suggest that the addition of known information helps to improve motor performance in unusual contexts. By adopting the “negative image” of conventional robotic approaches, our experiments tend to provide effective information for the design of useful interfaces for humans facing altered environments; thus opening up the scope of possibilities.