Our experiments suggest a mechanistic link between MAO-B-dependent GABA synthesis and neuronal synchrony in the SCN, raising the question whether reactive gliosis in the SCN and early weakening of circadian cycles in AD could be linked via the dysregulation of physiologically occurring rhythms of GABA production (Brancaccio et al, 2021; Hastings et al, 2023). Here, MAOB is linked to Alzheimer disease.