Decreased Activation of Brain Networks Post-Concussion
(HealthDay News) – Injured athletes show decreased activation of right hemisphere attentional networks in the post-concussion period, with hyperactivation seen at seven weeks post-injury, according to a study published in the September issue of the Journal of the International Neuropsychological Society.
Thomas A. Hammeke, PhD, from the Medical College of Wisconsin in Milwaukee, and colleagues examined the natural recovery from sports concussion using data from 12 high school football athletes with concussion and 12 matched uninjured teammates. Participants were assessed with symptom rating scales, tests of postural balance and cognition, and event-related functional magnetic resonance imaging during performance of a load-dependent working memory task at 13 hours and seven weeks post-injury.
The researchers found that during the acute period, injured athletes showed the expected post-concussive symptoms and cognitive decline with decreased reaction time (RT) and increased RT variability on working memory task. At seven weeks, full recovery was apparent. In injured athletes relative to controls, brain activation patterns showed decreased activation of right hemisphere attentional networks during the acute period. At seven weeks post-injury, a reversed pattern of activation was seen. Among the injured athletes, the changes were concurrent with a reduction in self-reported post-concussive symptoms and improved cognitive test performance.
"In this study of closely matched concussed and control athletes, we have demonstrated underactivation in right hemisphere attentional networks within 24 hours of injury, followed by hyperactivation at seven weeks post injury," the authors write. "This pattern of change in brain activation in the concussed athletes coincided with reduced post-concussive symptoms and improvements in neurocognitive performance."
One author disclosed receiving income from personal injury medicolegal work.