HTR2A and supranuclear palsy, progressive, 1: In area 24′ (Fig. 1f), patients with PSP with no to mild tau pathology (Wilks’ lambda = 0.003, chi-square = 55.124, p < 0.001 by omnibus test) showed higher GABAB, pBZ, and 5-HT2 receptor densities than did control subjects, whereas patients with PSP with moderate to severe tau pathology (Wilks’ lambda = 0.017, chi-square = 44.973, p = 0.001 omnibus test) presented higher NMDA, GABAB, pBZ, and serotonin receptor type 1A densities than control subjects.