Central Insulin Sensitivity in Individuals With Type 2 Diabetes (T2D) and at Risk for Developing T2D

Beside well described peripheral effects, insulin can also affect the human central nervous system. Centrally acting insulin seems to have an influence e.g. on whole-body metabolism and food intake. Targeting insulin receptors in the central nervous system can modulate peripheral insulin sensitivity as well as pancreatic insulin secretion. In humans, the effect of insulin can be measured in different brain areas as estimate of central nervous insulin sensitivity. Reduced central nervous insulin sensitivity, called "central insulin resistance," has been associated, for example, with obesity, unfavorable body fat distribution, and impaired cognitive functionality. Recently novel subtypes and risk clusters of diabetes and prediabetes have been identified. In this study the investigators want to investigate and compare central nervous insulin sensitivity as well as cognitive function in the different diabetes and prediabetes risk clusters.