In higher tau activity carriers (A), PC 9 connectivity was also markedly strengthened in the PD group relative to controls [F(1,61) = 56.1, p < 0.0001, ηp2 = 0.48], whereas group differences were not as large in GG carriers with lower tau activity [F(1,41) = 7.3, p < 0.01, ηp2 = 0.15]. Here, MAPT is linked to Parkinson disease.