A new study in the USA has revealed that playing football for a season or so at school or college level can cause a disruption. Gowtham Krishnan Murugesan, M.S., research assistant in the Department of Radiology at UT Southwestern Medical Center in Dallas, Texas, who conducted the study, presented it at the annual meeting of the Radiological Society of North America (RSNA).

“This research demonstrates that playing a season of contact sports may affect normal gray matter pruning in high school and youth football players,” he said.

The brain is a complex network of neural connections, which required removing unused connections. “Pruning is an essential part of brain development,” Murugesan said. “By getting rid of the synapses that are no longer used, the brain becomes more efficient with aging.”

He conducted the study among 60 youth and high school football players who had had no history of developmental, neurological or psychiatric abnormalities and concussion.  The players were asked to wear Head Impact Telemetry System (HITS) helmets, which were equipped with accelerometers or sensors that measure the magnitude, location and direction of impacts to the head. The real-time data obtained from the helmets were used to calculate the risk of concussion exposure for each player.

Based on the data, the players were divided into two groups: 24 high-impact players and 36 low-impact players.

He then performed pre- and post-season resting state functional (fMRI) scans on the players and analysed the fluctuations in power within five components of the default mode network (DMN), which is a network of regions deep in the gray matter areas.

At the end of the season, the results showed power surges and increase in gray matter volume in the frontal DMN in the high-impact group.

“Disruption in normal pruning has been shown to be related to weaker connections between different parts of the brain,” Murugesan said. “Our study has found a significant decrease in gray matter pruning in the frontal default mode network, which is involved in higher cognitive functions, such as the planning and controlling of social behaviors.”

He then studied biomechanical data from this same group and found that most head impacts occurred during practice.

“By replacing high-impact practice drills with low- or no-impact drills, the overall head-impact exposure for players can be reduced,” Murugesan said.

The researchers also suggested that minor modifications to the game could also be implemented to reduce full-speed contact.

“The new National Football League kickoff rule eliminating the running start is an example,” Murugesan said.

Now when you see your favourite player making blunders at the end of the season, do not blame them. The frequent in-game head collisions and the resultant debris on the brain are causing all those blunders.