Postural and emotional changes following repeated exposure to standing at a virtual height

Title: Postural and emotional changes following repeated exposure to standing at a virtual height. 

Karoline Rzyski, Emma I Nielsen ,Martin Zaback, Minh J Luu, Mark G Carpenter

Affiliation: School of Kinesiology, University of British Columbia, Vancouver, BC

Postural threat influences standing balance control, yet only some of these changes are attenuated with repeated exposure to the threat (Johnson et al. 2019; Zabacket al. 2019). This study used virtual reality to repeatedly expose subjects to a height-induced postural threat to determine if similar emotional and postural changes are observed. We hypothesized that repeated exposure to a virtual-height would minimize the emotional response, however, most threat-related balance control changes would remain unchanged. Seven healthy young adults (6  females) completed a series of 60-s quiet standing trials while wearing a head-mounted display and immersed in a virtual lab standing on a “Low” height ( 0.8m above ground,  away from the platform edge; 2 trials) and “High” platform (3.2m above ground, at platform edge; 15 trials). Each trial was followed by a seated rest. Fear of falling, perceived anxiety and confidence, and attentional focus were measured using questionnaires. Electrodermal activity (arousal) and forceplate-derived centreof pressure (COP) measures were recorded for each trial. Fear, anxiety, confidence, arousal, and attentional focus all significantly changed with initial exposure to a virtual-height and were subsequently attenuated following repeated exposure. In contrast, most height-related changes in balance control did not adapt with repeated exposure. These results suggest that some threat-related postural changes are context dependent, and repeated exposure to virtual heights can be used to examine relationships between emotional state, attentional focus, and postural control.

Acknowledgements: Funded by NSERC