Figure 1

Outline of the experimental schedule. Wister rats were randomized into sham operation, moderate TBI (TBI), and repetitive mild TBI (rmTBI) groups. Fourteen days before surgery, rats were acclimated to all behavior testing environments and pretraining, including the Y maze, radial maze, passive avoidance, rotarod, inclined plane, and modified neurological severity score (mNSS). One day before surgery, the neurobehavioral pretests were performed. On day 0 (D0), rats received a sham operation or a single TBI 2.1 atm) or rmTBI (1.5 atm). Three days later (D3), the rmTBI group received another single rmTBI (1.5 atm). The MRI observation was performed from D3 (sham and TBI groups) or D6 (rmTBI group) to 9 months (M9). The behavioral tests were performed from D7 to M9. Then, the rats were sacrificed and the brains were removed for histological assays.