RÉSUMÉ
Objectve:To observe the change of functional connectivity(FC)characteristic and its correlation with cognitive flexibility in type 2 diabetes mellites(T2DM)patients with cognitive flexibility decreased.Methods:A retro-spective analysis was performed in 24 T2DM patients with cognitive flexibility decreased(T2DM+CD),34 T2DM pa-tients without cognitive flexibility decreased(T2DM-CD)and 31 healthy controls(HC).Wisconsin Card Sorting Test(WCST)and the Stroop Color Word Test(Stroop)were respectively used in three groups of subjects to assess cognitive flexibility and functional magnetic resonance imaging(fMRI)scans was used to assess the FC.The differences of cogni-tive flexibility were found between three groups of subjects.The differences of FC between the bilateral(Left and Right,L.and R.)striatum(ST)and the dorsolateral prefrontal cortex(dlPFC)were found between three groups of subjects.Further analysis was focused on the interactive effect of T2DM and cognitive flexibility on FC changes.Results:Com-pared with T2DM-CD and HC,the number of response administered,errors responses,perseverative response,and time in WCST of T2DM+CD were significantly increased,while the number of correct responses was decreased.In Stroop,the number of correct,word-color contradiction and correct word-color indifference in T2DM+CD were lower than HC.In T2DM+CD,FC between L.ST-L.dlPFC,R.ST-L.dlPFC and R.ST-R.dlPFC were decreased,and decreased FC between R.ST-R.dlPFC was associated with cognitive flexibility scale scores.There existed an interactive effect between T2DM and cognitive flexibility on FC changes.Conclusion:Decreased FC between ST and dlPFC is the neural mechanism of cognitive flexibility impairment in T2DM.