M100907 administration was found to attenuate both DOI-induced HTR in sham subjects (Figure 2C) and mTBI-elicited potentiation of DOI-induced HTR (t = 12.35, p ≤ 0.0001), indicating a requirement of intact 5-HT2A-mediated signaling in mTBI-induced hypersensitivity to DOI administration. This evidence concerns the gene HTR2A and concussion.