New Faculty Research Spotlight
Mark E. Lester, Department of Physical Therapy
Using 360 Video to Study Postural Control in a Virtual Environment (VE)
"I became intrigued by recent developments in video technology and began to wonder if we could create a VE from 360-degree videos of a physical environment and test whether people actually move similarly in both.”
As a physical therapist with over 25 years of experience in military healthcare and doctoral training in motor control and neuroscience, I’ve had a keen interest in postural control for most of my career. Postural control is the technical term for balance and is foundational for every skilled movement we do. Postural control isn’t just about static balance, like assuming a yoga pose; it’s required for dynamic activities as well, whether that’s reaching for a book on a shelf, walking across the lawn, or running hurdles at a track meet. In the military, optimizing postural control improves operational task performance like moving under fire or breaching an obstacle. Muscle, joint, and nervous system injury or disease can impair postural control and lead to diminished function, decreased physical activity, and increased risk of falling. In the military, postural instability can reduce physical performance and combat effectiveness.
Postural control is an interplay between our sensory and motor systems. Our central nervous system uses information from our visual, somatosensory (sensory nerves), and vestibular (inner ear) systems to determine where we are in space in order to produce stable, coordinated movements. The more we are exposed to various types and magnitudes of postural challenges, the better we learn how to adapt to new postural threats. However, balance training in a clinical, laboratory, or gym setting makes it difficult to replicate the dynamic sensory and motor conditions we experience in the real world that promote this adaptability.
Immersive virtual environments (VE) provide a promising alternative to traditional balance training paradigms because of their ability to replicate real world situations in a controlled setting. One problem, though, is that these platforms typically require specialized equipment and personnel for operation, making them space and cost prohibitive for use outside of a research lab. Another problem is that since the VE is computer generated, we don’t really know if how people move in the real world is similar to how we move in a VE.
I became intrigued by recent developments in video technology and began to wonder if we could create a VE from 360-degree videos of a physical environment and test whether people actually move similarly in both. I was able to secure funding from the U.S. Army Medical Department Advanced Technology Initiative (AAMTI) program to test these questions.
This project is currently taking place at Joint Base San Antonio with active duty military personnel. We created several militarily relevant tasks to look at postural control under static and dynamic conditions. We are also looking at dual task conditions, where we combine a dynamic task with a progressively harder cognitive task. Participants perform each task in a physical environment and, on a separate day, perform the tasks in the 360-video VE played through a head-mounted display. We are comparing movement patterns between environments using kinematic data captured from a suite of wireless wearable sensors worn at the head, torso, trunk, feet, and wrists.
Each task requires participants to engage LED lighted targets with a simulated rifle or pistol in a specified order. The tasks include two static tasks where participants engage targets from a standing or kneeling position; one dynamic task where they walk an hourglass shaped course and have to make large and small turns while engaging targets; and a straight walking course where they engage targets and perform the dual tasks.
Early information from this project is promising, and I believe this concept has great potential for future research and practical application. Producing the 360-video VE is relatively inexpensive and it seems to replicate some real world tasks well. It also seems to provide a good medium to study skilled movements in a controlled setting. While more research is needed, leveraging 360-video content may provide a means for greater application of virtual training paradigms to learn new skilled movements or relearn movement patterns impaired by injury or disease.