Dynamic Visual Stimulations Produced in a Controlled Virtual Reality Environment Reveals Long-Lasting Postural Deficits in Children With Mild Traumatic Brain Injury

Thomas Romeas; Selma Greffou; Remy Allard; Robert Forget; Michelle McKerral; Jocelyn Faubert; Isabelle Gagnon

doi:10.3389/fneur.2021.596615

Dynamic Visual Stimulations Produced in a Controlled Virtual Reality Environment Reveals Long-Lasting Postural Deficits in Children With Mild Traumatic Brain Injury

Front Neurol. 2021 Nov 25:12:596615. doi: 10.3389/fneur.2021.596615. eCollection 2021.

Authors

Thomas Romeas^{1

2}, Selma Greffou¹, Remy Allard¹, Robert Forget^{3

4}, Michelle McKerral⁵, Jocelyn Faubert¹, Isabelle Gagnon^{6

7}

Affiliations

¹ Faubert Laboratory, École d'Optométrie, Université de Montréal, Montréal, QC, Canada.
² Institut National du Sport du Québec, Montréal, QC, Canada.
³ School of Rehabilitation, Faculty of Medicine, Université de Montréal, Montréal, QC, Canada.
⁴ Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal - IURDPM, Montréal, QC, Canada.
⁵ Department of Psychology, Université de Montréal and Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal - IURDPM, Montréal, QC, Canada.
⁶ Montreal Children's Hospital, McGill University Health Center, McGill University, Montréal, QC, Canada.
⁷ School of Physical and Occupational Therapy, Faculty of Medicine and Health Sciences, McGill University, Montréal, QC, Canada.

Abstract

Motor control deficits outlasting self-reported symptoms are often reported following mild traumatic brain injury (mTBI). The exact duration and nature of these deficits remains unknown. The current study aimed to compare postural responses to static or dynamic virtual visual inputs and during standard clinical tests of balance in 38 children between 9 and 18 years-of-age, at 2 weeks, 3 and 12 months post-concussion. Body sway amplitude (BSA) and postural instability (vRMS) were measured in a 3D virtual reality (VR) tunnel (i.e., optic flow) moving in the antero-posterior direction in different conditions. Measures derived from standard clinical balance evaluations (BOT-2, Timed tasks) and post-concussion symptoms (PCSS-R) were also assessed. Results were compared to those of 38 healthy non-injured children following a similar testing schedule and matched according to age, gender, and premorbid level of physical activity. Results highlighted greater postural response with BSA and vRMS measures at 3 months post-mTBI, but not at 12 months when compared to controls, whereas no differences were observed in post-concussion symptoms between mTBI and controls at 3 and 12 months. These deficits were specifically identified using measures of postural response in reaction to 3D dynamic visual inputs in the VR paradigm, while items from the BOT-2 and the 3 timed tasks did not reveal deficits at any of the test sessions. PCSS-R scores correlated between sessions and with the most challenging condition of the BOT-2 and as well as with the timed tasks, but not with BSA and vRMS. Scores obtained in the most challenging conditions of clinical balance tests also correlated weakly with BSA and vRMS measures in the dynamic conditions. These preliminary findings suggest that using 3D dynamic visual inputs such as optic flow in a controlled VR environment could help detect subtle postural impairments and inspire the development of clinical tools to guide rehabilitation and return to play recommendations.

Keywords: balance; children; mild traumatic brain injury (mTBI); perception-action coupling; postural instability; sensorimotor control; virtual reality.