Associations of olfactory brain activation and functional connectivity with neuropsychological test scores and diabetic parameters. Associations of olfactory brain activation and functional connectivity with neuropsychological test scores and diabetic parameters. A: Positive association between the activation of the left parahippocampus (lPara) and 2-h postprandial C-peptide was observed in the group with diabetes (black circles) but not in the control group (white circles). Meanwhile, the seed-based functional connectivity was significantly associated with 2-h postprandial C-peptide (B), 2-h postprandial insulin (C), z scores of cognitive domains including memory (D), processing speed (E), and executive function speed (F), as well as total scores of olfactory behavior tests (G). Partial r and P values were obtained after adjustment for age, sex, and education. P < 0.05 was considered significant. FC, functional connectivity; L, left. Zhou Zhang et al. Diabetes 2018;67:994-1006 ©2018 by American Diabetes Association