Characteristics of Papez Loop Neural Network in T2DM （Type 2 Diabetes Mellitus）

Inclusion Criteria: 1. T2DM patients met the diagnostic criteria for diabetes (WHO, 1999) with a duration of 3-20 years; The control group met the criteria of fasting blood glucose \< 6.1mmol/l and glycosylated hemoglobin \< 5.7%; 2. right-handed, aged 45-70 years, with ≥8 years of education; 3. no contraindications to MRI scanning such as electronic and metal device implantation; 4. The visual acuity or corrected visual acuity and binaural hearing can meet the needs of the evaluation, and can cooperate to complete the examination. 5. without a history of substance abuse or dependence, evaluation is not used during the period of calm sleeping pills and antidepressants, not long-term use of drugs to improve cognitive. Exclusion Criteria: 1. patients with acute metabolic complications or a history of severe hypoglycemia; 2. severe heart, liver, lung, kidney and hematopoietic system diseases; Hyperthyroidism or hypothyroidism; Stroke, alzheimer's disease, epilepsy, Parkinson's disease and other neurological history; A history of mental illness such as depression, mania, or alcohol dependence; History of loss of consciousness due to neurological diseases or traumatic brain injury; 3. one month before the laboratory examination, with a record and surgical trauma infection;