Influence of virtual reality height exposure on cognitive load and visual processing during balance beam walking
Balance is a critical component of many activities of daily living and sports. Effective balance control relies on the input from multiple sensory systems, such as proprioceptive information about one's body position and visual cues from the surrounding environment. Conclusions for how balance varies during dynamic tasks have primarily been determined through low-variability tasks that may not offer adequate challenges for healthy individuals. Beam-walking has been proposed as a more effective and direct measure of dynamic balance for both healthy and diseased populations. Balance beam parameters such as length, width, and height can be altered to introduce various challenges for a wide range of individuals. In response to height exposure during beam walking, individuals tend to display cautious gait patterns and limited visual exploration of the surrounding environment. Head mounted displays, or immersive virtual reality (VR), allow individuals to experience a cognitive sense of presence similar to that experienced in a real environment, without the immediate risk of injury or danger. VR environments have been shown to induce physiological stress responses (i.e., elevated heart rate) that mirror those observed in real life situations. Further, investigating frontal lobe asymmetry during virtual height exposure and beam walking can provide insight on the approach or withdrawal behavior styles associated with immersive VR and challenging dynamic tasks. Thus, the purpose of this study was to observe how virtual reality height exposure induces stress and impacts balance performance, visual processing, and cognitive effort during beam walking. Sixteen healthy young adults (age = 22 ± 3 years, 7 males, 9 females) were recruited for voluntary participation. Participants completed a series of nine walking trials on a physical walkway with and without a virtual reality (VR) headset. The nine trials were divided into three walking conditions: no-VR (NVR), low-VR (LVR), and high-VR (HVR). Wireless electroencephalogram (EEG) and heart rate monitoring systems were used to record brain activity and physiological stress responses throughout all nine trials. For the VR conditions, participants wore a head mounted display and were first immersed in a city street landscape (LVR) and then up on a high-rise building (HVR). A virtual walkway that matched the physical walkway parameters was present in both VR environments. Balance performance significantly worsened from the NVR to LVR condition (p [less-than] 0.001) but slightly improved from the LVR to HVR condition (p [less-than] 0.05), while VR trial completion time significantly increased from the LVR to HVR condition (p [less-than] 0.05). The gaze behavior analysis revealed that participants spent most of their time viewing the three virtual walkway planks and the areas just below or around the walkway for both conditions (p [less-than] 0.05) and that there were no differences in object viewing time between the LVR and HVR conditions (p = 0.058). Frontal lobe alpha power significantly decreased from NVR to LVR and NVR to HVR (p [less-than] 0.05), yet no significant differences were found between LVR and HVR. Finally, participants exhibited elevated heart rate across all three conditions, with significant increases from NVR to LVR (p [less-than] 0.05), LVR to HVR (p [less-than] 0.05), and NVR to HVR (p [less-than] 0.001). These findings indicate that virtual reality height exposure can induce physiological stress responses as well as impact balance performance, cognition, and visual processing.
Herman, Callie. (June 2021). Influence of virtual reality height exposure on cognitive load and visual processing during balance beam walking (Master's Thesis, East Carolina University). Retrieved from the Scholarship. (http://hdl.handle.net/10342/9351.)
Herman, Callie. Influence of virtual reality height exposure on cognitive load and visual processing during balance beam walking. Master's Thesis. East Carolina University, June 2021. The Scholarship. http://hdl.handle.net/10342/9351. August 12, 2022.
Herman, Callie, “Influence of virtual reality height exposure on cognitive load and visual processing during balance beam walking” (Master's Thesis., East Carolina University, June 2021).
Herman, Callie. Influence of virtual reality height exposure on cognitive load and visual processing during balance beam walking [Master's Thesis]. Greenville, NC: East Carolina University; June 2021.
East Carolina University