Objective: We sought to determine the duration of cognitive impairment after sports concussion.
Methods: We conducted a study with a prospective design in which 729 athletes underwent preseason baseline testing by being administered a computerized neuropsychological test battery, followed by retesting at regular intervals after they sustained sports-related concussions. A control group consisting of nonconcussed athletes drawn from the same baseline population underwent testing at parallel intervals.
Results: Cognitive impairment in this primarily American Academy of Neurology Grade II sample of boxing concussions was apparent on the day of injury and at 1 to 2 days postinjury. Recovery of cognitive performance occurred during the 3- to 7-day interval. Comparison with control subjects showed that absent or attenuated practice effects, in addition to frank deterioration from baseline, were indications of recent concussion.
Conclusion: The present findings of recovery during the 3- to 7-day interval postinjury are consistent with the American Academy of Neurology Grade II return-to-play practice parameters suggesting a 1-week time-out from participation in contact sports.