Post-stroke visual neglect affects goal-directed locomotion in different perceptuo-cognitive conditions and on a wide visual spectrum

Article type: Research Article

Authors: Ogourtsova, Tatiana^{a; b; *} | Archambault, Philippe S.^{a; b} | Lamontagne, Anouk^{a; b}

Affiliations: [a] School of Physical and Occupational Therapy, McGill University, Montreal, QC, Canada | [b] Feil-Oberfeld Research Centre, Jewish Rehabilitation Hospital, Laval, QC, Canada

Correspondence: [*] Corresponding author: Tatiana Ogourtsova, School of Physical and Occupational Therapy, McGill University, 3654 Promenade Sir-William-Osler, Montreal, H3G 1Y5, QC, Canada. Tel.: +1 450 688 9550 Ext. 4823; Fax: +1 450 688 3673; E-mail: tatiana.ogourtsova@mail.mcgill.ca.

Abstract: Background:Unilateral spatial neglect (USN), a highly prevalent and disabling post-stroke deficit, has been shown to affect the recovery of locomotion. However, our current understanding of USN role in goal-directed locomotion control, and this, in different cognitive/perceptual conditions tapping into daily life demands, is limited. Objectives:To examine goal-directed locomotion abilities in individuals with and without post-stroke USN vs. healthy controls. Methods:Participants (n = 45, n = 15 per group) performed goal-directed locomotion trials to actual, remembered and shifting targets located 7 m away at 0° and 15° right/left while immersed in a 3-D virtual environment. Results:Greater end-point mediolateral displacement and heading errors (end-point accuracy measures) were found for the actual and the remembered left and right targets among those with post-stroke USN compared to the two other groups (p <  0.05). A delayed onset of reorientation to the left and right shifting targets was also observed in USN+ participants vs. the other two groups (p <  0.05). Results on clinical near space USN assessment and walking speed explained only a third of the variance in goal-directed walking performance. Conclusion:Post-stroke USN was found to affect goal-directed locomotion in different perceptuo-cognitive conditions, both to contralesional and ipsilesional targets, demonstrating the presence of lateralized and non-lateralized deficits. Beyond neglect severity and walking capacity, other factors related to attention, executive functioning and higher-order visual perceptual abilities (e.g. optic flow perception) may account for the goal-directed walking deficits observed in post-stroke USN+. Goal-directed locomotion can be explored in the design of future VR-based evaluation and training tools for USN to improve the currently used conventional methods.

Keywords: Cerebrovascular accident, hemineglect, gait, locomotion, trajectory deviation

DOI: 10.3233/RNN-170766

Journal: Restorative Neurology and Neuroscience, vol. 36, no. 3, pp. 313-331, 2018