Multiple Object Tracking Scores Predict Post-Concussion Status Years after Mild Traumatic Brain Injury

The diagnosis of concussion remains challenging, particularly in cases where several months have passed between a traumatic brain injury (TBI) and clinical assessment. Tracking multiple moving objects in three-dimensional (3D) space engages many of the same cognitive processes that are affected by concussion, a form of mild TBI (mTBI), suggesting that tests of 3D multiple object tracking (3D-MOT) may be sensitive to post-concussion syndrome (PCS) after a brain injury has occurred. To test this, we evaluated 3D-MOT performance (using NeuroTracker^TM) against Sports Concussion Assessment Tool results for cognition, balance, and symptom severity in a large sample (N = 457) of male and female participants between the ages of 6 and 73 years. 3D-MOT performance in subjects under age 13 was not impaired by a history of concussion, but was positively associated with cognition and balance. 3D-MOT performance in those 13 and older was negatively associated with concussion symptom severity and positively associated with cognition and balance. 3D-MOT was selectively impaired in subjects with probable PCS (pPCS), defined using the 95th percentile of symptom severity for subjects with no history of concussion. A decision tree predicted concussion status with 95.2% overall test accuracy (91.1% sensitivity, 97.8% specificity), using concussion history, age, and 3D-MOT score. Persons with a history of concussion in the past 37 days were predicted to have pPCS if they were ≥35 years of age, or if they were <35 years of age but achieved scores below 1.2 on the 3D-MOT. These results demonstrate the potential of 3D-MOT for pPCS diagnosis and highlight the increased vulnerability to concussion symptoms that comes with age.