Get started
Work

Head orientation modifies the contribution of vestibular information to trunk control during walking

Year: 2024
Type: conference-paper
Abstract: Electrical vestibular stimulation (EVS), which produces illusions of self-movement, is widely used to probe the vestibular system. Previously, we found EVS induced phasic, vertebral level specific paraspinal muscle activity during walking. This indicates that vestibulospinal reflexes contribute to trunk stabilization during walking. Head orientation changes the direction of the EVS induced illusion (e.g., in the frontal plane when facing forward and in the sagittal plane when the head is turned 90 degrees to the side) and modifies the vestibulospinal reflexes during standing. We investigated whether and how head orientation changes the contribution of vestibular information to paraspinal muscle activity during walking. Sixteen participants walked on a treadmill for 8 minutes at 78 steps/min and 2.8 km/h, in four conditions defined by the presence of EVS and head orientation (facing forward or leftward). Bipolar electromyography (EMG) was recorded bilaterally from the paraspinal muscles from the C7 to L4 vertebral level. Coherence, gain and delay between EMG and EVS were characterized. Significant EVS-EMG coherence in the paraspinal muscles was observed at heel strikes in both head orientations. The leftward head orientation significantly decreased the EVS-EMG coherence and gain compared to walking with head forward. This overall decrease may be explained by the effectiveness of passive stabilizing control in the sagittal plane during walking. However, the decrease in coherence was only significant at the left-lower and the right-upper vertebral levels around left heel strikes. This is possibly because the head yaw rotation pivot is located posterior to the origin of vestibular reference frame. Therefore, a leftward head orientation will induce an offset of the vestibular axis to the left relative to the trunk reference frame. Consequently, motion to the left encoded by the vestibular signal would be smaller than motion to the right, causing an asymmetric response to vestibular afference. This study confirmed the contribution of vestibular information in trunk stabilization while highlighting that this contribution is impacted by head orientation during walking.
Authors: Li, Y.C.; id_orcid 0000-0001-9470-6132, Lemaire, Koen, Bruijn, Sjoerd; id_orcid 0000-0003-0290-2131, Brumagne, Simon, van Dieen, Jaap; id_orcid 0000-0002-7719-5585
Language: English
Open Access status: green
OpenAlex ID: W7010201844
FWCI:
Cites:
Cited by:
Related to: