Citation

Killeen T, Easthope CS, Filli L, Lőrincz L, Schrafl-Altermatt M, Brugger P, Linnebank M, Curt A, Zörner B, Bolliger M. R. Soc. Open Sci. 2017; 4(1): e160993.

Affiliation

Spinal Cord Injury Center , University Hospital Balgrist , Forchstrasse 340, 8008 Zurich , Switzerland.

Copyright

(Copyright © 2017, Royal Society Publishing)

DOI

10.1098/rsos.160993

PMID

28280596

PMCID

PMC5319362

Abstract

Human arm swing looks and feels highly automated, yet it is increasingly apparent that higher centres, including the cortex, are involved in many aspects of locomotor control. The addition of a cognitive task increases arm swing asymmetry during walking, but the characteristics and mechanism of this asymmetry are unclear. We hypothesized that this effect is lateralized and a Stroop word-colour naming task-primarily involving left hemisphere structures-would reduce right arm swing only. We recorded gait in 83 healthy subjects aged 18-80 walking normally on a treadmill and while performing a congruent and incongruent Stroop task. The primary measure of arm swing asymmetry-an index based on both three-dimensional wrist trajectories in which positive values indicate proportionally smaller movements on the right-increased significantly under dual-task conditions in those aged 40-59 and further still in the over-60s, driven by reduced right arm flexion. Right arm swing attenuation appears to be the norm in humans performing a locomotor-cognitive dual-task, confirming a prominent role of the brain in locomotor behaviour. Women under 60 are surprisingly resistant to this effect, revealing unexpected gender differences atop the hierarchical chain of locomotor control.

Language: en

Keywords

arm swing; central pattern generator; cognitive control; dual-task; gender; motor control