Ever hear the expression, “Nobody really knows anything when it comes to concussions?” It explains the murky recovery timelines, inconsistent symptoms from patient to patient and growing list of long-term effects suffered years after head trauma.
But what if that could change and we could no longer feel in the dark about concussions? The results of a revolutionary study published by a team of Canadian and U.S. researchers in Brain: A Journal of Neurology outline a unique way to monitor brain activity in the moments after someone sustains a concussion. Working on the technology since 2012, the researchers have unlocked a completely different method to conduct in-game protocol for hockey or dozens of other sports. The work was the result of collaboration between neuroscientists from the Health and Technology District in Surrey, B.C., and the Mayo Clinic Sports Medicine Center in Rochester, Minn.
The goal of the study was to discover a more accurate and immediate way to recognize and understand how brain function is affected not just long-term after a concussion – but in the minutes and hours immediately following a brain injury.
“Neural tissue requires sufficient time to heal after injury and athletes are susceptible to potentially far more severe re-injury if cleared to return before fully recovered (Giza and Hovda, 2015),” the study states. “However, there is mounting evidence demonstrating that neurophysiological impairments persist even after the observable clinical signs and symptoms have subsided (Kamins et al., 2017). Sports medicine professionals are currently limited by a lack of access to more sensitive, objective measurements to assist with evidence-based treatment decisions (McCrory et al., 2017; Smith et al., 2017). There is a growing urgency to develop practical approaches that use objective, physiological measures, which are also rapidly and easily deployable in both sport and clinical settings.”
Enter the new approach introduced from the Health and Technology District and the Mayo Clinic. They believe they’ve finally found an objective, practical, rapidly deployable tool. The metric it measures: “brain vital signs.”
So how does it work? Somewhat like an electroencephalography or EEG test, explains Shaun Fickling, the study’s lead author and a PhD student at Simon Fraser University. The researchers attach something like a swim cap outfitted with a thin wire that “listens” to brain signals as it processes auditory information – such as certain combinations of words. It measures auditory sensation, basic attention and cognitive processing. The test is non-invasive, fully automated and takes less than 10 minutes.
“It looks at how the brain responds to the pattern changes embedded within that auditory stimulant,” Fickling said. “The healthy brain responds in a very characteristic way. The impaired brain or the concussed brain doesn't quite respond to pattern changes in the same way, and that affect is measurable, and that is how we put that together into the brain vital signs’ framework.”
The test subjects for the study: 47 members of a tier-3 male Jr. A team across the course of two seasons. Every player on the team had his brain vital signs scanned at the start of each season to establish a baseline. If anyone sustained a diagnosed concussion on the ice, the researchers pulled him off and immediately scanned him rinkside using a portable device outfitted with the brain-vital-signs testing technology. Then, after the players went off for the standard team concussion protocol and got cleared for a return, the researchers scanned their brain vital signs again. That established a baseline for immediately after the injury – and for what the differences in brain vital signs would look like for a player cleared for a return to play. At the end of each season, every player was also scanned for the sake of comparing pre- and post-season brain vital signs.
The portability of the measurement technology created the opportunity for quicker, more accurate assessments of brain function immediately after injuries were sustained. So now for the most important question: what were the study’s findings?
One crucial and alarming discovery: even players deemed fit to return to games showed differences in their brain vital signs pre- and post- injury.
“In this field, there’s a big focus to find an objective physiological measure of the impact of concussions, and for concussed players we saw very, very strong evidence of changes in their brain vital signs,” said Dr. Ryan D’Arcy, the Health and Technology District’s co-founder, an SFU professor and the study’s senior author. “And when they were cleared to return to play using the existing concussion protocol, we still detected residual impairments, particularly in their attention processing and the markers for attention processing.”
Another key finding of the study: the research team examined players who hadn’t been diagnosed with concussions all season, compared their brain vital signs from the start to the finish of the season – and found changes in brain function.
“We found significant differences with their cognitive processing speed slowing (after the) season, suggesting some sort of sub-concussive impact due to the physical nature of the game,” Fickling said.
So not only does the study suggest concussed players cleared to play still show signs of brain impairment, but even those who don’t sustain concussions suffer some sort of damage over the course of a season because of the repeated minor impacts that come from playing a contact sport.
The kneejerk reaction to this information might be to ask, “Does that mean players aren’t taking nearly enough time off after concussions – and that hockey is far more dangerous for the brain than we even thought, considering the findings on sub-concussive trauma?” Not necessarily. The findings could eventually mean the exact opposite. If the breakthrough in brain-vital-sign technology means a more accurate and physiologically objective understanding of how concussions affect the brain, that in turn can improve the ability to monitor and properly treat brain injuries. As Dr. D’Arcy puts it, that could eventually mean speeding up the recovery timeline for concussions.
“You can’t treat what you can’t measure, and now that we can actually measure this in a sensible way, we can actually look at the most innovative treatments to shorten the timeline and get players back and into the game – but at full health,” Fickling said.
Fickling and Dr. D’Arcy hint that more news is forthcoming on some breakthroughs in the “how” element of treating concussions, but there’s nothing to report just yet.
Often, when we read studies like these, the sense is that they’re exciting ideas that will take months or years to become available for mainstream use. That’s not the case. The brain-vital-sign technology is ready. It’s been applied to competitive athletes in game situations. The Health and Technology District and Mayo Clinic are working actively to make their tool available for worldwide use right now.
We'll likely never stop learning new things about the breathtakingly complex organ that is the human brain, but this study has the look of a watershed moment for our understanding of concussions. How long before a major pro circuit considers trying it out?
(To read the study in its entirely, go to https://academic.oup.com/brain/article/142/2/255/5288791)