In contrast, changes in SC–FC coupling in PD low visual performers (compared to high visual performers) were not significantly correlated with changes in dopaminergic but rather to cholinergic (CHRNA2, CHRNA3, CHRNA4), serotoninergic (HTR1A, HTR5A) and noradrenergic (ADRA2A) receptors (Fig. 5B, Table 3 and Supplementary Table 3 for the full neurotransmitter gene expression results). Here, HTR1A is linked to Parkinson disease.