INSR and type 2 diabetes mellitus: 2016). An animal experiment using 125I‐labeled insulin to evaluate insulin receptors in the rat brain uncovered their extensive distribution throughout the olfactory bulb, cerebral cortex, hypothalamus, hippocampus, amygdala, and septum (Hill et al. 1986). The brain regions significantly correlated with IR in our study coincide with the above findings. Most studies about T2DM attributed the phenomenon of alterations in volume to glycemic dysregulation, dyslipidemia, and accompanying vasculopathy (Cui et al. 2022).