Kim M, et al. - In this prospective cohort study, experts aspired to explore if functional (electrophysiological) parameters are related to changes in the structural (microvascular) parameters in diabetic retina. The sample consisted of 366 eyes of patients with diabetes mellitus (DM) and 157 eyes of healthy controls. Compared with the controls, the amplitude and implicit time of the rod and cone and combined response electroretinogram (ERG) b‐wave were significantly reduced and prolonged in the eyes of DM patients. A positive association was found between the amplitude and vessel density (VD) of the superficial plexus and a negative link between the implicit time and superficial VD in the scotopic and combined response b‐wave. The clinical manifestation of diabetic retinopathy (DR) is accompanied by functional and structural impairments. It was also found that these neural impairments, assessed by ERG, were associated with superficial VD. However, this correlation was not present in healthy and early DR groups. Such results carefully indicate that neuronal dysfunction is linked to vascular dysfunction in type 2 diabetes.