The neurological repercussions of playing football occur sooner than we think. Two new studies from the University of Texas Southwestern Medical Center and Wake Forest Baptist Medical Center found that youth football players who experience concussions had less activity between default mode network (DMN) regions than those who didn’t have a history of concussions.
Researchers at the Advanced NeuroScience Imaging Research lab (ANSIR), Elizabeth M. Davenport, PhD, a postdoctoral researcher, and Gowtham Krishnan Murugesan, PhD, a biomedical student, used machine learning to evaluate the brain changes in 26 football players ages 9-13. During the entire length of the season, the players wore a Head Impact Telemetry System (HITS), a helmet that identifies and pinpoints impacts to the head, and uses sensors that determine the magnitude and direction of the hit. Using functional MRI (fMRI) scans, Davenport and Murugesan implemented five algorithms to place the players in one of three groups: high-exposure, low-exposure, or non-contact. According to the Radiological Society of North America, “The algorithm discriminated between high-impact exposure and non-contact with 82 percent accuracy, and low-impact exposure and non-contact with 70 percent accuracy.”
In the second study, 20 high school football players underwent a magnetoencephalography (MEG) scan so that researchers could get a broad scope of their brain activity and analyze the eight sections of the DMN. Out of this group, fifteen of these players had never experienced a concussion, and the remaining five had suffered through at least one concussion. At the end of the season, the students underwent another MEG scan, and the researchers found that the five players with a history of concussions had “significantly lower connectivity between DMN regions.” On the other hand, on average, players who were concussion-free had “an increase in DMN connectivity.”
"The brains of these youth and adolescent athletes are undergoing rapid maturation in this age range. This study demonstrates that playing a season of contact sports at the youth level can produce neuroimaging brain changes, particularly for the DMN," said Murugesan.