A demonstration of the virtual reality test used in Dr. Gary Wilkerson’s study of perceptual decision-making and concussion history. Participants wearing a VR headset respond to moving visual objects by turning their heads, reaching and stepping in specified directions. The figure was previously published in Brain Sciences, an open-access journal.
A University of Tennessee at Chattanooga researcher has found that virtual reality-based measures of movement and decision-making may help identify subtle, lasting effects associated with multiple concussions.
Dr. Gary Wilkerson, a professor in UTC’s Graduate Athletic Training Program in the Department of Health and Human Performance, is the lead author of “Virtual reality, machine learning, and statistical modeling reveal an association between multiple concussion history and impaired perceptual decision-making,” published in PLOS One—a peer-reviewed, open-access journal of the Public Library of Science.
Wilkerson’s co-authors are Dr. Mohammad Joghataee and Dr. Ashish Gupta of Auburn University.
Their study examined virtual reality test results and self-reported concussion histories from 202 physically active adolescents and young adults. The researchers found that participants with a history of two or more lifetime concussions were more likely to record a low score on a measure of perceptual decision-making than participants who reported one or no prior concussions.
The finding does not establish that multiple concussions caused the observed differences. Still, Wilkerson said it adds to growing research suggesting that the effects of repeated concussions may persist well beyond the time when an athlete’s symptoms appear to have resolved.
“We often view a sport-related concussion as a minor injury that only temporarily disrupts normal brain function,” Wilkerson said, “but accumulating research evidence indicates that multiple concussions can produce cumulative adverse effects that persist and worsen over time.”
A concussion is a type of mild traumatic brain injury. A person may recover from noticeable symptoms, such as headache, dizziness or difficulty concentrating, while subtle changes in the brain’s ability to process information and guide movement may be difficult to detect using conventional clinical tests.
“Highly advanced diagnostic imaging can identify concussion-related brain abnormalities, but the clinical tests now available are not sensitive enough to consistently detect subtle impairments,” Wilkerson said. “Precise virtual reality measurement of perceptual-motor responses appears to offer an objective way to identify people who may have a subtle deficiency in brain processing.”
For the study, participants wore a virtual reality headset and responded to visual objects moving across the display. Depending on the object’s direction, they rotated their necks, reached with an arm, and took a step in a specified direction.
The test was designed to measure speed, accuracy and consistency as participants made rapid movement decisions based on changing visual information.
Researchers analyzed 13 virtual reality performance measures using machine learning and statistical modeling. They compared results among participants reporting no concussion, one concussion or multiple concussions.
The clearest distinction emerged between those reporting two or more concussions and those reporting one or no concussions. Participants with two or more concussions were more likely to have a low score on the study’s Action Initiation Efficiency (AIE) measure, which combines measures of how quickly, accurately and consistently a participant begins a neck movement after seeing a visual stimulus.
Compared to participants who demonstrated high AIE values, those with low AIE values had 5.75 times greater odds for having a history of two or more concussions.
Wilkerson said a lower score may point to a reduced ability to respond effectively when conditions change quickly.
“The speed, accuracy and consistency of body responses to visual detection of objects moving across a virtual reality display may reflect brain processing efficiency,” he said. “A low Action Initiation Efficiency score may be an indicator of a suboptimal capability to effectively respond to rapidly changing environmental circumstances.”
That distinction, the study said, matters in sports, where athletes frequently must assess visual information and make immediate decisions while moving. The researchers said a subtle impairment in perceptual decision-making could affect both performance and injury risk.
Wilkerson said the study’s approach differs from traditional concussion evaluations because it measures a person’s response to a task that combines perception, cognition and movement rather than examining those functions separately.
“Sport participation requires athletes to rapidly process visual inputs and make numerous decisions under highly demanding conditions,” he said. “We need better ways to identify subtle impairments that may not be apparent during standard clinical testing.”
The research builds on Wilkerson’s nearly 35 years of work in sports injury prevention and cognitive performance. His earlier research has examined methods for assessing and training the perceptual-motor skills athletes use to process visual information, make decisions and execute movement.
Dr. Eric Hungenberg, head of UTC’s Department of Health and Human Performance, said Wilkerson’s work reflects a sustained commitment to research and education focused on athlete health and injury prevention.
“I commend Gary’s resolute pursuit of knowledge aimed at mitigating athletes’ susceptibility to injury,” Hungenberg said. “Equally admirable, he has demonstrated a commitment to not just grow the body of literature, but has exhibited a passion for working with athletes directly, educating them on the relationships between mental health, sleep quality, performance and injury reduction.
“After over a quarter of a century at UTC, I have great admiration for the man who continually seeks ways to expand his research line, display mentorship, and detect and implement new technology. UTC is very fortunate to have Dr. Wilkerson as a faculty member.”
The authors stressed that additional research is needed before the findings can be applied in clinical settings. The study was retrospective and cross-sectional, meaning it examined previously collected test results and concussion histories at one point in time. The concussion histories were self-reported, and the research could not account for every factor that might influence test performance—including sex, age, prior injuries or differences in athletic experience.
The researchers also noted that the study involved a limited number of participants with a history of multiple concussions. Independent studies involving broader groups of athletes and nonathletes will be needed to confirm the findings, assess their reliability and determine whether virtual reality testing can contribute to concussion screening, management or injury-prevention efforts.
A PDF of the full study is available here.
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Department of Health and Human Performance
Master of Science in Athletic Training
