Specifically, we aimed to: (1) characterize the transcriptomic heterogeneity of microglia in T1D mouse brains using snRNA-seq; (2) determine the spatiotemporal relationship between Aβ oligomer accumulation, microglial activation, and cognitive decline; and (3) investigate the mechanistic role of TREM2 in regulating microglial migration, phagocytosis, and mitochondrial function under high-glucose conditions, with a particular focus on the PI3K/Akt/mTOR signaling pathway. The gene discussed is TREM2; the disease is Mental deterioration.